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a64pilot
04-30-2003, 09:56
I am getting close to doing the fuel filter thing myself. Will probably use a Racor filter and install it like Hoot. (Seems like I copy him alot, Thanks Hoot)
Anyway the question is, Is anybody with the Racor filter system or the Cat filter system having problems with excessive air? I am defining problems as loss of prime, starting difficulty or engine stalling.
I would like to hear from people that are having no problems as well. I agree that fuel cannot be too clean, so I would like additional filtration. The problem is that I don't want to take a truck that always starts and runs reliably and turn it into one that doesn't. I know that bleeding a filter of air is an exceptionally easy task, but I believe that it would be beyond my Wife and Daughter. I am also concerned about possible stalling or power loss in traffic as the attitude of the truck changes. If anyone with the Racor or Cat have had such problems please speak up.

hoot
04-30-2003, 10:44
Don't thank me. Thank John Kennedy, Nomad56, and all the others before me. I just watched and chose the pieces I liked best and put one together.

No air issues at all. Matter of fact my truck has never run better.

a64pilot
04-30-2003, 10:50
Hoot,
Actually the thanks was for the pyro bulb installation location, If you weren't the first you described it best. DRL mod, I like those kind, Free and actually no mod, can return to stock at any time, accomplished exactaly what I wanted though. ETC.

56Nomad
04-30-2003, 11:48
a64pilot,

Thanks go to John Kennedy who located the best place to
put a secondary fuel filter.

Pictures of my installation are located below. I have absolutely
no air collecting in my system. I have checked both my primary
and secondary bleeder's several times and NO air. I've got over
2000 miles on my truck since intallation. As far as performance,
other than getting a bit better mileage, I see no change. My
truck runs like a top!

I like the location because when I have to change out both filters
at 20,000 miles, they are conveniently located and any spillage
of fuel will end up on the ground as opposed to on engine parts.

The installation is really pretty easy. I didn't even take off my
tire to do it!

I choose the Racor set up for several reasons. The size, the water
separator, the fact that our Duramax has a Racor as primary filter.
Because the assembly head has different ports for locating the
fuel inlet and outlets, if you decide to mount it in a different
position, it gives you more options. They give you plugs to seal
the ports you do not need.

Also, here are my costs to install it:

$25.41 Parker Hose (250 LB PSI) (7 feet)
$82.38 Filter head with Racor R60 filter
$2.83 (4) Worm Gear Clamps
$2.72 (2) Barbed Brass Fittings
$3.95 (1) Brass petcock
$3.50 Bolts and bracket

[ 04-30-2003: Message edited by: 56Nomad ]</p>

Kennedy
04-30-2003, 19:55
Keep in mind that no air does NOT mean it isn't present. Most filters do not have a substantial volume above the suction point for air to collect so it just passes through. I have not heard of any stalls from air, and am really quite certain that 10 or so pumps on the primer without opening the bleeder will get a no-start going.


Time may prove that the Common rail system does not mind air, but IMHO, ignoring it is like ignoring a cyst or a lump or a funky mole that doesn't appear to be getting any bigger, but definitely not better either... :eek:

[ 04-30-2003: Message edited by: kennedy ]</p>

a bear
04-30-2003, 22:04
John,
You got mail

NWDmax
04-30-2003, 23:38
Okay John,If 10 pumps or so gets a no start going where does the air go that caused the no start in the first place?

The daily bleeding is getting kind of old.

Who has the remote bleeder so I can go more than 20 miles before having to bleed again.

I'm not b****in about your product as its a very nice piece of work but I don't have the time right now to trace down the source.

Don't know of any conclusive evidence of where its coming from anyway.

I'll let you know how my 100 mile fishing trip goes tommorrow! smile.gif

DanB
04-30-2003, 23:56
Hi,

Pumping the primer 10 or so times sounds right to me. I'm not sure where the air goes but I can tell you that it gets harder and harder to push the primer in. As you pump, pressure builds up. Then when you go to start the vehicle, it doesn't fire right up; it cranks for a couple seconds. The combination of pressure and cranking may force the air out of the line.

Cheers,
Dan.

mackin
05-01-2003, 03:44
Aren't you opening up the (a) bleeder to allow the air to escape?? I would think it would defeat the purpose if you were to just to pressurize and force thru ...



MAC

[ 05-01-2003: Message edited by: mackin ]</p>

a64pilot
05-01-2003, 06:21
All,
John is right, air is present. I just don't know if it is bad and right now it would appear that you 3 choices. 1 Leave well enough alone, If it ain't broke don't fix it. 2 Trap the air, by whatever means and frequently bleed. 3 install a filtersystem that allows the small bubbles to pass through, essentially leaving it in stock configuration except for additional filtration.
If air wasn't present then you could not push the primer even one time. Fluid is not compressable and hydraulic lock would prevent it. I don't see how you are introducing air into the system by only pumping the primer pump though, unless the pump leaks.
I am theorizing two things. 1 when you compress the fuel to high pressures, the tiny bubbles will essentially disappear. 2 The system is designed to be self purging. As long as you don't exceed the designed capacity air is returned to the tank and only fuel is sent to the injectors. Remember only a theory with no facts behind it.
This is not Bosch's first diesel injection system. This is not the first common rail inj. system. Bosch's engineers are not idiots, surely the air in diesel thing was addressed and designed in.
Finally I don't believe in magic. If a magnet would increase power and fuel mileage while reducing emissions or an intake tornado would, They would come from the factory that way.
I am questioning the utility of devices like the fuel preperator (sp)? unless you are getting enough air to cause loss of power etc.

NWDmax
05-01-2003, 06:53
My primer/bleeder pump never gets that stiff(har har).It pushes down firmer once its pumped up but you don't have to push real hard even then.
Whats yours like? :cool:

a64pilot
05-01-2003, 07:11
My Daughter has my truck now so I cannot check, I would think that it has a pressure relief valve in it if it never gets "stiff". If it does then it is a smart design as it is "idiot proofed".

Kennedy
05-01-2003, 07:54
Keep in mind, Bosch built the system, and GM used it's typical plumbing style as used on non diesel vehicles...

If one gets an air lock and pushes the primer, it will likely push the air in the pump through with the return fuel. Not much you can do about that, but at least the air will process quickly , and mostly through the low pressure side of the pump.

Blake,

Something changed in your system, and it would be well worth a look-see. It does not take long at all to install the clear hose. From there, if it is the rear section, a guy could easily plumb hose from the tank sender to the steel line behind the fuel cooler OR run right up to the engine...

chuntag95
05-01-2003, 07:54
Mine gets stiffer, but not so much you cannot press it. No matter how hard I have tried, I cannot get all of the air out. I am at option number 2 of a64's 3. Trap and bleed often, that is until I can design an auto bleeder that works in vacuum. Nothing like a good design challange. :D

a64pilot
05-01-2003, 07:56
OK I re-read the 10 or so pumps will get a no start going and now I understand. I thought that 10 or so pumps would initiate a no start, now I see it meant that it would fix a no start condition.
NWDmax, I assume that pressurizing the air will allow it to pass through the pump. I assume the pump will not pull much of an air vacuum as it is designed to pump liquid not gas.
On Edit: I realized that if 10 or so pumps will fix a no-start condition then a boost (lift) pump should never allow it to happen in the first place. Just a thought.

[ 05-01-2003: Message edited by: a64pilot ]</p>

chuntag95
05-01-2003, 08:01
a64,
On the air vacuum, I think you would only not pull in the event the line was void of liquid. The pump should work through the air until it starts pulling fuel in. My swimming pool works like that anyway. Totally different designs, but at least I can see that one and what happens.
John,
Do you have clear hose to and from your Mega as well as to the OEM filter? I was thinking about ordering some clear fuel line and changing it all.

Chris

a64pilot
05-01-2003, 08:31
Chris,
The pump that I was refering to was the eng. driven one. I believe that if it got an air bubble large enough to fill the pump cavity then it may loose prime and cause a no start condition due to the loss of prime. Maybe the increased RPM will allow the pump to pass bubbles while at operating RPM, but starting RPM may not allow the pump to pull enough head to pass the bubble, it would explain why pressurizing the suck side of the pump will fix a no start condition also.

DanB
05-01-2003, 09:15
Hi,

I do not open the bleed screw or even know where it is located. I do one of two things:

1) Push on the primer until it gets fairly hard to press all the way down (after you press it the first few times you should feel it start to stiffen). Then press it down a couple more times. LOL! Crank and give a bit of gas until running.

That's what I do and it acts up at most once a day. If I don't keep pressing beyond stiff and into hard then the problem will persist throughout the day.

2) Have it towed to the dealer and/or let it sit overnight.

Hope that clarifies,
Dan.

jbplock
05-01-2003, 10:41
Chris,

I'm with you... Nothing like a good design challenge! My JK Megfilter is trapping air, which I believe is a good thing! I have been bleeding it every 200 to 300 miles of driving with out any starting or drivability problems. I'm also pretty sure I don't have any vacuum leaks, although I'm going to do some more testing just to be sure. Assuming leaks are not the source of my "gas", I'm considering several methods to automatically bleed the trapped air. Even if this is overkill at least it's fun!
:D :D

chuntag95
05-01-2003, 11:48
Bill,
What ideas have you come up with. Sound like we are looking for the same solution. Automation! I have been looking, but keep coming back to needing a positive pressure. Either I pump or I add a pump. The second has been discussed quite a bit, but I was thinking a temp deal at startup or shutdown for a few seconds and have it bypassed or open flow the rest of the time.

jbplock
05-01-2003, 12:13
Chris,

I'm still thinking

chuntag95
05-01-2003, 12:25
Hey, put an optical sensor on the sight glass so when it sees through, it will run, but if it's full of fuel, it doesn't. :D Now we are getting complicated. I LIKE IT! 40,000 for the truck and 20,000 for the design flaw corrections. :eek:

a64pilot
05-01-2003, 12:33
Bill,
Has anyone tried adding an inline lift pump like the 6.5's to see if the air problem goes away? I don't know what the vapor pressure of diesel fuel is but if it is low enough for heated diesel then maybe what you are trapping is fuel vapor and not air. If you get air under pressure then so is every other Diesel eng that I know of.
If you want to bleed off all of the trapped air you could find a very low flow rate pump, plump it in exactly as you described and let it run all of the time. It would hurt nothing that I could see, it would never allow any air to build up, and worst case if it failed it would only allow air to build up again and not restrict fuel flow as a failure in an inline pump might.

chuntag95
05-01-2003, 12:57
a64,
There you go ruining all the fun by simplifying the whole thing. :D Just return the air back to the tank, and if it goes back through, you catch it in the mega again. You just remove the injector pump and the injectors from the path for air. You could probably even use it to prime your mega. :cool:

a64pilot
05-01-2003, 14:08
Chris,
I didn't come up with it, Bill did. I believe that you are right about priming. I believe that it would prime both filters though. I have also been wondering with all of this pumping how long the stock primer was going to last before it became an air leak itself due to worn out seals. Without it being underneath a rubber bulb I have been suspicious of it's life span.

chuntag95
05-01-2003, 15:21
I went looking at fuel pumps. I found some relatively inexpensive one, but all seemed to be a higher flow than I wanted. What is the posibility of pulling too much fuel and starving the engine since it's a vacuum system? How low of a flow do you guys think we need. I was thinking the minimum pressure (1.5 psi) that we could find. Also, I think a check valve would be good to insure no back streaming.

[ 05-01-2003: Message edited by: chuntag95 (Chris) ]</p>

jbplock
05-01-2003, 19:16
Chris/A64,

Good discussion going here! Regarding the inline lift pump, dpearl-river and CntrlCalDmax have done this and eliminated air by pressurizing the line. This eliminates the air (or fuel vapor?) from collecting in the MegaFilter. But, if the air is still is in the fuel (?), it could it still come out when the fuel is depressurized in the injector (cavitation )? I would like to leave the system running under suction, since as JK pointed out, this is the way the Bosch pumps run in Europe. If I add the pump to suck out the collected vapor from the bleeder, I would run it at each fill-up when the engine is shut down (It would also be nice for priming the system when changing filters). I found a pump in my Borg Warner catalog that seems like it would work. It’s a free flow (Borg Warner) EP20S rated at 5.3-6.7 psi at 26-32 GPH (similar to the 6.5 lift pump but with 5/16 hose nipples). It’s the same type that Dr. Lee used on his 6.2L. The AutoZone website has an equivalent E8012S pump for 37.99. I’m also worried about wearing out the primer so I would like to do some thing soon.
smile.gif

imported_
05-01-2003, 20:17
good discusion, and frustrating problem.

I am having air in fuel problems with my cat filter in the JK position. I origanally thought it was install related, so I redid the install, gooped all the treads, tightened up all the clamps. This helped dramatically. I now only have a slight "hic-up" from the engine exactly 7 secs after every start up if I don't hit the primer pump. It is a slight hestitation lasting about 1-2 seconds. After that everything runs fine. I have put on 1000miles this week with no loss of power, noticably better fuel economy and only the slight hesitation after start up.

56Nomad
05-01-2003, 20:38
Brad,

Just curious. Are you using your CAT bleeder
to remove the air? Or are you bleeding the
OEM bleed screw? How much air are you getting?

NWDmax
05-01-2003, 20:45
Went fishing at Lake Chelan today which is 40 miles from here.

Upon returning the truck did the start and die deal at the boat launch.

I bled this sucker this morning about 1 a.m.

Total mileage since bleed about 50.

Needless to say I've got a major suck going on somewhere now just need to find it.

I'll try the primer pump only next time and see if it'll still start.

Thanks for the input it really helps!
Blake :confused:

chuntag95
05-01-2003, 20:56
Bill,
That's why I suggest the check valve, to keep the system a vacuum system. The idea of just running it to a switch and hitting it while you fill up is a good one. You don't even have to open the hood. :D I got my air trap parts in tonight from the big brown truck. I put it all together and to my surprise, it all fit. :eek: Now, tomorrow is the fun part, where to install the beast. There are not a large number of options with it's size. I have considered adding it to the bleeder port on the mega. A couple of adapters from 1/8" to 1/4" and all will fit right behind the headlight. I could add a tee in the top or an elbow an plum it to a pump. Then all I need is the tee in the return line and a switch. Might have to run to Autozone and Lowes in the morning before I start.

imported_
05-01-2003, 21:48
56Nomad

My initial bleeding procedure was as follows;
open OEM screw and pump until pressure is built and diesel is spewing. Continue to maintain pressure (I keep priming the pump and close screw) Move to the cat filter and repeat process. I continue to pump (after both bleed screws are closed) until stiffness is felt in the primer pump. Start the truck, all is fine. I then moved to bleeding at the cat filter only. And now I am not bleeding, just pumping.
The oem filter was changed about a week prior to the cat filter install to ensure it wasn't the problem. (seal, O-ring etc) and I don't think it is. The truck ran fine before the cat filter.

I wasn't sure how much I was bleeding so I did some experimenting.

If I open either bleeder without touching the primer pump it sucks air into the system. Because of this I am unsure what is trapped air and what is introduced air when I crack the bleeders. If I give one pump on the primer pump before opening, both bleed screws spew fuel. If I pump twice before starting the truck, without opening the bleed screws, everything is OK and no hesitation when I start the truck.

To be honest, I am more confused now then ever. :confused: I run dual Racors on my Land Cruiser and don't have this problem, and it is way more sensitive to air in the fuel lines. I usally have to crack the fuel lines at the injectors to purge the system after a fuel filter change or it it doesn't run right.

I even questioned the push locks at first. I returned to the store to inquire about their integrity. The shop foreman rigged up a regulator on a hose with a check valve and attached it to one barb of the push lock. It held 150psi of air for over an hour before we dismantled it. :(

jbplock
05-02-2003, 05:02
Chris,

I'm curious to see your air trap setup. Can you post some pics when your done? It sounds neat! I also agree on the check valve(s). A picture would explain this much better but I'm hoping to find a valve that will go in-line after the added bleeder pump that opens at a specified pressure and also prevents fuel from flowing back from the return line to the MegaFilter when the engine is running. I was also thinking of adding a check valve in the fuel return path to prevent the pressurized fuel (and air) drawn from the bleeder from back flowing though the added return line tee (to the rails). This second valve may not be necessary but I'm not sure if pushing fuel (and air) up the return line to the rails during bleeding would hurt anything (better safe than sorry). I think the desired path for the bleeder is to only push fuel/air back to the tank through the return line, but not to the rails. I guess we could also run a separate line all the way back to the tank.

Brad,

When you open your bleeder and hear a hissing sound I believe this is sucking air into the system as you said. Mine does this also, even after sitting for a few days. I think this implies that the system is holding a vacuum (good) and is not leaking (good). The question is then. Where is the vacuum (low pressure air/vapor) coming from? The fuel (?). If it's coming from the fuel and we are trapping it that's good (I think). Only problem is how to automatically remove this vapor build up with out periodic manual bleeding with the OE primer pump.
smile.gif

chuntag95
05-02-2003, 08:11
Bill,
I don't have a place to post my pictures, but I will see if Silver Bullet will do it for me. If you want, send me an email at my handle at attbi dot com, (Leave out the parenthesis part. tongue.gif ) and I will email them to you.
I am in the middle of a redesign. I want to add the pump to purge the mega. I want to put it post sight glass, so I can see what kind of air I am removing. My bigest problem so far is where to tap into the return line. The cleanest place is the return line from the injector pump. It is a rubber hose 3/8" and well hidden. The other place would be the QD by the firewall. The only problem is how with the QD. If you could put in a sliced piece that had the QD on each end, no problem, but I don't see that happening. Second, you could just cut the darn thing off and replace with hose and clamps. Very possible solution, but unable to return to stock. Plus, I agree with you that adding a check valve before the tee in would protect the system and be a warmer and fuzzier design.
Tommy,
Did you just cut off the QDs and replace with hose?
Chris

a64pilot
05-02-2003, 08:13
Chris,
If you wanted to decrease the flow of an available pump you could easily do so with a restricted orifice. I.E. put a carburetor Jet in the line going from the pump to the return line of the fuel system or something similar. It would take some experminting to find the flow rate you want. I agree the check valve would be a good idea, again at the worst I can't see how it would hurt.

chuntag95
05-02-2003, 10:16
I went parts shopping and got a pump, fittings, hose, but no check valves. I did find some 3/4" NPT, but it was going to take 3 bushings and a barb fitting to get there (each end). I will order the correct ones instead. I will set up my sight glass and take a few pics to let you guys see what a twisted mind like mine can come up with. :D

a64pilot
05-02-2003, 10:38
Chris,
I used to be a contract welder years ago, anyway IIRC just about any welding supply house should stock small check valves that are installed on a cutting torch to prevent the possibility of reverse flow of the flame. We used to call them "back flow preventers". They are a little shorter than a AA battery, but bigger around and should I believe have 1/8 npt nipples already on it, one female and the other male.

retiredalaskan
05-02-2003, 10:43
I've been following this fuel filter problem for a while. BUT HAS ANYONE decided if pre oem or post oem is better.

pinehill
05-02-2003, 15:37
retiredalaskan,

pre-OEM: better in that a frame-mount is less likely to raise eyebrows at a dealership, and MAY be more accessible for filter changes.

post-OEM: better in terms of how filters are normally set up, ie, coarse filter first, then fine filter. This configuration should also give signicantly longer fine filter life.

Take your pick.

With regard to Bill Plock's idea of adding a low pressure electric pump between Megafilter bleed port and the fuel return from the Bosch injector pump:

This sounds like an excellent idea. Two momentary contact switches could be installed to actuate the pump, one in the engine compartment for priming after filter changes, and one in the cab for bleeding air at fuel stops, or occasionally before startup. I do see the need for a high quality check valve between the filter and the return, primarily to prevent additional filter air intrusion from that source. The pump would also need to be self-priming to assure that it would eliminate the accumulated air. I wouldn't think that an additional check valve between the fuel return T and the injector pump would be necessary.

chuntag95
05-02-2003, 15:44
a64,
I'll check out the welding supply. Thanks for the tip.
I got my sight glass installed on top of my Mega filter, at the bleed port. Third time was the charm. First rev looked good, but was to go inline. No real good place to put it where it would not bang around, so on to rev 2. Rev 2 looked good on top of the mega, behind the headlight. Used JKs bleeder on top and you could bleed with a stubby if you wanted to :D . One tiny little problem, the light would not go back in :mad: I twisted it every way and even shave a little off the plastic, but that only got it to where you could force it. I needed to extend my "jog" farther back. A little rearranging, and no problem, except for the part where the nipple would not come out and then crushed and broke off in the elbow :eek: :mad: . Change from 1/8 to 1/4 in a different place, and I now have the right parts. :cool: But the 1/8" nipple I have is too long. :( I have a die! and so I cut that sucker off and rethreaded it. Could have used a tad shorter, but I got it to all work. Got the leaks fixed and filled up. Now to see how it does over the weekend. So far, I only have to drive 15 minutes and I have enough air to be below the sight glass, but that was before my last rev and I also pulled the QD on the firewall and filled with grease. We shall see. I will send Silver Bullet the pictures to see if he can post on his board.
Later,
Chris

NWDmax
05-02-2003, 17:29
Chris send them to me too please.

My e mail is mountainmax62@msn.com

Thanks.
Blake

NWDmax
05-03-2003, 11:07
10 pumps gets my no start conndition going with no bleeding.

At least I can put my long screwdriver away for now....

56Nomad
05-03-2003, 11:17
NWDmax,

Glad to hear that you have options :D

But I wonder where does the air go??
Maybe, back to the tank?

NWDmax
05-03-2003, 11:35
56Nomad,

earlier in this thread JK says that the air gets pushed through the pump into the return line that goes back to the tank.

Thats if I'm reading it correctly.

I guess I'm going to buy some clear hose to try and find out where the big air is coming from.

Primer pumping is an every day deal now.Think I'll punch a hole in the hood so I don't have to open it to pump! :D

imported_
05-03-2003, 12:45
As of about the last twenty starts I have had no priming issues with the cat filter in the JK position, but I still get a slight hesitation after about 7 sec after initial start. I took it to the cat dealer to get their opinion and he was baffled, so for now I am going to live with it.

My mpg has sky rocketed after this instal, a combination of summer fuel and better filtration i think. I got 22mpg on my last fill. I usually average around 16mpg.

56Nomad
05-03-2003, 13:16
"I still get a slight hesitation after about 7 sec after initial start.".............

I't must be that your GM is having a hard time
figuring out this CAT thing......... kinda like spittin up a hair ball :D :D :D

felpa41
05-03-2003, 17:12
I had the Kennedy Mega Filter kit installed in my truck recently. I've gone about 500 miles since, mostly short trips of less than 50 miles each.

So far, not a single starting or hesitation problem. It runs just like it did before the installation.

It looks like I may get better mileage by about 1 to 1.5 mpg. Only one fill up so far since I have the big fuel tank. If I got a 1 mpg improvement, I would be really pleased.

I have never touched the primer or had to do anything to correct a fuel related problem. Did I just get lucky or did John improve the kit since you guys installed your kits?

imported_
05-03-2003, 17:28
I think the general would have a hard time figuring out anything that works right on my truck, :( everything that is doing what it is supposed to, the general had very little to do with. :rolleyes:

FirstDiesel
05-03-2003, 18:01
felpa41

I'm willing to bet you that you have a filter full of air. The design of the Mega Filter traps the air. You don't really know it's there until you get a ton of it. Pump the primer until it's hard and then open the vent screw on the Mega. Betcha no fuel comes out but you hear an air hiss.

[ 05-03-2003: Message edited by: FirstDiesel ]</p>

hoot
05-03-2003, 18:57
Hmmm. I don't have to bleed any air and don't need a pump. Mines post-OEM. Works like it's not there.

jbplock
05-03-2003, 19:40
Great discussion and good ideas continue to flow!

Chris,
I like your idea to install the bleeder pump after the sight glass. I was looking at the Grainger catalog and was trying to figure out which sight glass you used. Is it the one designed to view fluid levels in a tank or the inline type?

I bought an E8012S pump from Autozone today. It looks very similar to a 6.5 lift pump except it has what I believe is a check valve on the input. If I blow into both ends it will only pass air one way. When I get some time I’m going to test it with my cheap-o Wal-Mart version of a mighty-vac. I also found some inline check valves at mscdirect.com that look like they would work. Regarding the return line splice, it sounds like you are way ahead of me. I’ll check out the 3/8 return hose from the FI pump you mentioned. I also decided against messing with the QD return line near the valve cover (at least for now I also want to keep things reversible). In fact initially, I was thinking of using the pump with a piece of clear hose on the outlet and draining to a jar until I decide where to plumb the return permanently. It would be better than pumping the primer. I also like pinehill’s idea to have two switches wired in parallel. One to run the pump from under the hood, one for in the cab. (switches should probably be momentary too).

Hoot,
Which filter are you using? If it isn't the MegaFilter and it doesn't have a long clean side nipple, any air in your system will pass right through.

smile.gif

[ 05-03-2003: Message edited by: jbplock ]</p>

jbplock
05-04-2003, 04:34
Blake,

Since “10 pumps gets (your) no start condition going with no bleeding”, you may have a small leak that is allowing the fuel to drain back from the line feeding the pump. If there was a leak, and given the MegaFilter traps air when the engine is running, fuel could drain back into the Mega leaving an air/vapor lock. When you pump the OE primer with out bleeding, maybe it primes the line and pushes the air out the leak (?). Not sure this is your problem but something to think about.
smile.gif

a64pilot
05-04-2003, 08:36
Hoot,
I'd bet lunch money that the naturally occuring "air" is a normal operating condition and that the stock fuel system is designed to cope with it. I believe that the reason you and others are not having an air problem is that you are using fuel filters that were originally designed as fuel filters. The Racor,Cat and other fuel filter heads do not have the capacity to trap air so the small amount of "air" is passed along to the pump and delt with just as it was in a stock configuration. If you installed some form of an air trap I believe you would have the same problem.
I'm just curious to see if eliminating any entrained air will be of any benefit, of course I'm still trying to figure out how filtering the fuel would give you any measurable increase in fuel mileage. It just dosen't seem logical to me that none of the major Diesel manufacturers have a system to strip air from the fuel if their were benifits to be gained from it. I would also expect to see the OTR guy's filtering down to 1 micron or something if it increased mileage significantly. I have never driven OTR, but with as much fuel as they burn any mileage increase would have to save them a lot of money.

a64pilot
05-04-2003, 08:45
Retiredalaskan,
I am going post OEM. Here are some of the reasons.
1. The OEM filter has a water in fuel monitor so I want it to see the fuel first, yes you can buy aftermarket with the monitor, but it costs more.
2. The OEM filter will heat the fuel if necessary.
3. Racor at least warns against trying to filter to 2 microns with just one filter.
4. Going back to stock configurqation post OEM would appear to be an easier proposition than Pre OEM.
5. IMHO John's under the air box location appears to be the best I have seen.

NWDmax
05-04-2003, 09:26
Jb, I'm going to pump till firm and crack the bleeder before I even start it this morning.

We'll see if any air comes out or not.The longer the truck sits the more likely it won't start so I'm thinking I may have disturbed something when I put the Mega filter on.

At this point I just don't know........

Thanks for the help Bill smile.gif

[ 05-04-2003: Message edited by: NWDmax ]</p>

george morrison
05-04-2003, 10:40
A64Pilot, with regard to your excellent comment "of course I'm still trying to figure out how filtering the fuel would give you any measurable increase in fuel mileage. It just dosen't seem logical to me that none of the major Diesel manufacturers have a system to strip air from the fuel if their were benifits to be gained from it. I would also expect to see the OTR guy's filtering down to 1 micron or something if it increased mileage significantly."
I know it sounds difficult to imagine but I have recently shared an equally 'strange' device which significantly increases fuel mileage by simply passing diesel fuel through a rare earth metal environment, aligning, exciting molecules to facilitate burn. And the stupid device works! (and no, I do not sell the device and was *very* skeptical but am currently following fuel increases up to 10%!) This improvement is by aligning/exciting molecules only. NOW, when we filter down to 2 microns we are removing significant amounts of material which signficantly affect the burn rate, ratio, efficiency. These particles do not contain the same BTU content, burn characteristics of diesel fuel. By removing these particles, we are facilitating a much more perfect 'burn'.. Soooo, if this doubious black box, rare earth defice can significantly affect burn rates, our removal of burn impedement components CAN have a significant affect, especially given the ultra efficiency of our fuel system in the Duramax..
Hey, it was just a little over a year ago Caterpillar (one of the largest diesel engine mfg in the world) "discovered" that the 5 to 10 micron particle was destroying their fuel systems at an alarming rate. (alarming rate meaning systems/injectors failing before warranty was up and it was eating CAT's profits!)
Thus just because OTR truckers have not yet discovered the positive affects of ultra fine filtration does not mean that we are not at the leading edge of dieseldom here!!
George

56Nomad
05-04-2003, 10:52
OK George,

I bought into your increased mileage with adding my Racor and
It worked :rolleyes: BTW thanks!

Now...... Please tell us where we can find this magic box of "rare earth"
stuff for our trucks. Can you point us to a link?

Interesting that we have a physician here in the Bay area "Doc Wallace"
who sells "rare earth" snake oil that cures every disease known to man.
He is of "Dead Doctors Don't Lie" fame

[ 05-04-2003: Message edited by: 56Nomad ]</p>

NWDmax
05-04-2003, 13:46
Pumped till firm and had no air just fuel.
Started and ran real smooth non of the normal cold lope I usually get.
Does that tell us anything?
No clear fuel hose at the Schucks store here.The real parts stores won't be open till tommorrow.
Guess I'll have to start somewhere. :confused:

chuntag95
05-04-2003, 16:55
Sorry about going away, but the wife had her family reunion this weekend and I was forced to attend. :( Anyway, I have created an account on webshots and got the pictures of my sight glass uploaded. The link is http://community.webshots.com/user/chuntag95
I went on a 375 mile tear over the last 3 days. Everything from .2 of a mile to 150 non-stop. Every single time, there was air/fumes in the sight glass. The longest trip required the most pumping. I can pump up the system and purge all of the air out. I let it sit from an hour to all night without losing the fluid in the sight glass, but soon as I go, it shows. The volume of the sight glass (~15cc) isn't enough to really get a quantitative value, but I am considering looking for something bigger as a temp situation to get that value. Just on a side note, I cannot get air at idle :confused: but pulled around from the back of my house and it was full of air. Pumped like crazy and compressed the air enought to get liquid 1/2 way back up the sight glass.
I am going to see if I can go this entire tank without bleeding to see if I have any issues. I need to order a couple of check valves and work through the return line routing for next weekend. All ideas on where to plumb the return line will be appreciated. So far, the best bet is the hose next to the firewall, but I think that forces a replacement of the QD. I am not sure I want to cut the lines yet. There seems to be only one other spot, but the top half of the engine has to be removed. Alright, someone give me a good idea here. :D

a64pilot
05-05-2003, 07:59
George,
If you say it works I believe you. I am one of those people that have to see some things to believe it. It would seem that everything for sale by some people will improve fuel mileage. GM still has to meet CAFE standards or pay the goverment some kind of fine don't they? Don't all of the manufacturers have to? wouldn't it be to their advantage to install air intake tornadoes or fuel line magnets stock if it worked?
Remember in the early 70's when the 200MPG carb. was the rumor? I didn't believe it then and not so sure I do now.
Like the improved filtration. I'm not saying it won't improve mileage, but I'm having a hard time figureing out how removing an ounce or two of material from a thousand gallons or so of Diesel fuel will make much difference in mileage. Wear yes, and wear will be the reason I will install an additional filter. If I see increased mileage I will pleasently surprised.

Burner
05-05-2003, 10:52
64, Shoot me an email, please.

thanks,


Burner -----&gt; :D

george morrison
05-05-2003, 12:14
I only share the "rare earth' black box as an example of how state of the art diesel engines may well be affected by components which would have not indicated any level of fuel efficiency gain 10 years ago in a Cummins Big Cam IV engine. And no, I absolutely refuse to share the information on this rare earth black box deal yet as there is not enough data.. I have NO invovement with this rare earth deal and only share the information I have monitored to date (which is not enough data) on several test engines the unit is installed on. Long way to go.. Believe me, I have "been there done that" with respect to magic elixers and potential fuel savings. In my previous life I was VP of a large mining concern that wrote million dollar checks out each month for diesel fuel purchases. As little as a 1% efficiency gain had a signficant dollar savings.. No component we ever tried resulted in bottom line savings other than just good preventive maintenance..
I will keep all posted on the rare earth deal progress but the purpose was to share that if this variation of magic is actually working, then the removal of significant amounts of non-burning/ash producing components from diesel and its marked affect on fuel burn efficiency is very real..
George

[ 05-05-2003: Message edited by: george morrison ]</p>

a64pilot
05-05-2003, 12:33
Burner,
check mail

jbplock
05-07-2003, 05:26
For anyone that's interested, I put up some pictures of the tank-sender to steel line hose replacement. Click on JK_MegaFIlter in my signature (I finaly learned how to use the UBB codes :cool: )

[ 05-07-2003: Message edited by: jbplock ]</p>

hoot
05-07-2003, 06:11
If I'm not mistaken, I think there is a slight performance increase. Are we nuts?

a64pilot
05-07-2003, 07:05
Hoot,
Didn't you reroute your propane line at the same time you installed your 2nd filter?

hoot
05-07-2003, 08:13
Yes I did but I don't know what the effect was unless I put it back. I've cut the hose shorter so putting it back is not an option.

a64pilot
05-07-2003, 08:59
Hoot,
Was wondering if the hose being in front ot the MAF wasn't interfering with airflow measurments either due to turbelance or maybe the propane being a lot colder than ambient air or maybe the computer was measuring the propane as well as air or maybe something else entirely.
Any way maybe interfering with the MAF may result in lower power and now that it has been relocated, that may be the reason for improved performance. So,you may not be crazy. :D

chuntag95
05-07-2003, 09:03
Hoot,
You are just having that never ending wish of any change will bring more power. Did you fall off your 12 step program? LOL tongue.gif
On a serious note, what kind of mileage are you getting with all of the filters, propane, etc?

hoot
05-07-2003, 09:25
It's not fair for me to be declaring any gains without some kind of better proof.

When I straight piped it I don't think it made much difference.

I don't think the Amsoil air filter made much difference either except maybe egt but I did no back to back comparison.

When I got the 01 updates done 6 or 8 months ago, I felt that it ran smoother and stronger.

After doing this filter/lp hose relocation.. it definately got stronger. Without lp on.

I haven't checked my mileage since when i first had the truck when it was showing 16-17. Maybe it's time.

Sorry to say, still gettin the defueling. Every time I think I have it licked, I jump the gun and say it's fixed.

george morrison
05-07-2003, 20:28
Re: performance gains. As we have been discussing, I am working with this device straight out of Star Wars/Snake Oil city that 'aligns molecules' via running the fuel by rare earth metals. The thing costs $1200, is sealed and is manufactured in West Palm Beach, Florida, the scam capital of the world: however, the blamed thing is reducing fuel consumption on the order of 5 to 10%. This, by aligning molecules! Now, with the fuel filter we are really doing something! We are removing NON burning, ash producing garbage in significant quantities.. It makes some sense that yes, we ARE going to increase the efficiencies of our Duramax burn. I have data from fleets which have embarked on "ultra clean fuel" programs and have experienced anywhere from 1 to 5 percent improvement in fuel mileages. This not your imagination. Ultra clean diesel fuel has a significant impact on performance.
George