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Captain Mal
05-30-2003, 20:14
I'm now reading the posts on installing extra fuel filters along with the air-bleeding comments that went with them. I was going to order a second filter but it seems like they are not practical. Many of you don't mind bleeding air from a system every couple of hundred miles but just yesterday I drove 924 miles. The day before I went about 850 miles and today....

Well, it would be rediculous for me to consider an extra fuel filter if I would have to stop multiple times a day to bleed the filters. It also sounds like a threat to my safety to be towing large trailers and have to face multiple daily stalling and breakdowns because of extra filters and air problems. If heat is also a problem then the 112 degree run I had two days ago would be impossible with the extra filter.

Am I reading the posts right?

Oh, the 'stealer' that replaced my third defective injector wins the prize. It took four days from breakdown to installation and the charge was just at $1,400. That's $500 more than each of the other injecter failures cost me.

The moral is.....plan your breakdowns near reasonably priced 'stealers'.

FirstDiesel
05-30-2003, 20:44
Captain Mal

I have the Mega Filter. It's collecting air. I've never had a no start problem. Either before or after adding it. I haven't bled it in many hundreds of miles. There is probably air in there but I have no problem with the truck.

a64pilot
05-31-2003, 06:29
I think the Mega is the only one that is collecting air. If I were going through injectors at the rate you are I'd try something even if it were sacrificing a chicken or something.
I think Greg, the Amsoil guy is selling a Racor kit, but I'm not sure.
Just as there are other boxes than Juice there are other filter options as well. Ain't it great to live in a country that has options. ;)

Captain Mal
05-31-2003, 08:17
A64pilot,

There are chickens living at the house down over the hill from me. If you think it will work, I'll use one of the 22 rifles.

You now have me looking for a filter system that installs easily and works without a hassle. It may be that and/or a complete rebuild of my trucks' fuel system parts or ..... "I hear you calling; I'm Cummin(s)".

srubrn
05-31-2003, 11:36
Against my better judgement I am going to reply to this filter issue.

I put the first addtional filter on way back. It is a Stanadyne FM-100 with a 2 micron filter. Mounted under the frame rail in front of the fuel tank. It is 97% efficient, it works and no air or stopping and bleeding.

I do plan to go to a 6in. 5 micron filter when I run out of 6in. 2 micron filters so I can make it past 4300 miles without changing filters. If it's stopping up, it must be working. Redneck logic.

Also the unit can be bought for under a $100 with filter and filters are about $12 a piece. All this is available at Reliable Industries. Talk to Scott and tell hime Todd sent you.

Take a look at this link for a pic of my unit.

http://www.oldmacksrus.com/filter_picts.htm

LanduytG
05-31-2003, 12:31
Yes we do have a complete kit filter kit ready to install. The filter is a Racor 660 with bracket that bolts to the frame just in front of the fuel cooler. Also comes with fittings and hose. The filter takes about 30 mins to install. All you need is a small tubing cutter to cut the fuel line.

Greg

Captain Mal
05-31-2003, 12:50
Gregg and Todd,

You guys sure gave me a workout. After looking at Todd's pictures I went outside and got stuck under the truck. I mean STUCK!

The creeper was too high to go under the truck without putting it on the ramps. I got a piece of cardboard. My chest fit under the runningboard but my belly got stuck. Just could not slide back out.

I have been stuck under that darn running board for the past 1/2 hour. My wife heard me and was going to call the neighbor's place when I got her to use the compressor and add LOTS of air to both tires on that side of the truck. That worked as I had dropped the pressure 30lbs to return from California the last couple of days.

I'm breathing hard and laughing. I also think that changing a filter under there in below zero temps. at 4 AM in a Wyoming snowstorm would be a little difficult.

Thanks for the idea but I think I'll look for that chicken.

a bear
05-31-2003, 13:01
Todd,
Is the 97% efficiency per your prior fuel analysis? I searched the threads and couldn't find the results. How much additional vac is your system seeing when the filter clogs.

56Nomad
05-31-2003, 13:10
Greg,

I gave up on the frame mounted filter idea after I had installed
the R660 on the frame rail :( As I have written before, it took
me about the same time to re-install (move) this assembly under the
airbox than the original install on the frame smile.gif
Two big reasons I moved the filter assembly:

1. It clogs much too quickly as a primary filter
2. I hated having diesel fuel run down my arm laying under the truck

I used the same assembly bracket and fittings when I moved it
under the airbox. I had to buy some extra length of hose.

Greg, can you adapt your kit to hang under the airbox? In my humble
opinion, JK has found the best location for a secondary filter
assembly for our trucks.

GMCTRUCK
05-31-2003, 13:17
Actually one member (I'll let him decide if he wants to take credit publicly) came up with a great idea. All those trucks with secondary filters trapping air can install a pressure gauge, quick connects, and with 25ft of air hose they can go around and inflate tires, run an impact gun, heck maybe even just run the extra air back into the intake and pickup some HP. How much more practicle can you get than that. :D :D :D Guess you had to be there.

56Nomad
05-31-2003, 13:29
Captain Mal,

Are second fuel filters impractical? Absolutely not.
Only if you like to read a lot...... the specific reasons to add
secondary fuel filtration to our trucks have been covered
in great detail in previous posts (thank you George Morrison)
There has been excellent analysis why our OEM filters are
not adequately doing the job and there are good reasons why
we SHOULD improve the filtering of our fuel.

A majority of the installed Mega Filter assemblies trap air, however,
some of the members are enjoying the challenge in solving this problem.
If you are not so inclined...... don't invest in a Mega Filter.

Good thing is that we have lots of options. smile.gif

Victory Red
05-31-2003, 13:57
I for am finishing my secondary setup(CAT) tomorrow morning. I expect my factory system to live throughout the warranty but not much beyond(Murphy's Law). For a little bit of effort, time and money a secondary setup can be added. Which one you choose is your choice.

I chose CAT mainly because of the availability of parts. I don't know as of yet what issues(if any) I'll encounter in the way of air. If it's minimal(bleed every few fillups) I'll keep it, if it's constant, I'll restore to factory and try some of the other options.

Bottom line is $4000 is a lot for injectors. Until cheaper aftermarkets come out I'm not taking any risks.

[ 05-31-2003, 04:45 PM: Message edited by: Victory Red ]

ndamico
05-31-2003, 14:14
Here's my question... if you install a 2-micron PRE-OEM filter and you get 12-15k out of it, what's wrong with that concept? AFAIK nothing... granted the small 2-micron filters do clog quick, but look at the big CAT one.

easy install, no diesel all over you when changing (you can get to it from its side, not below), no messing with post OEM setup (if you have a picky dealer like me).

the downside is that you don't have to change your OEM filter for a long time. big deal! tongue.gif

besides, with the PRE-OEM, it gives you a reason to discard some of those GM quick-disconnect lines...

JMHO.... tongue.gif tongue.gif tongue.gif tongue.gif tongue.gif

[ 05-31-2003, 02:24 PM: Message edited by: ndamico ]

GM Smitty
05-31-2003, 14:31
Well, I just changed my PRE-OEM Racor 660R today for the first time. 4800 miles and absolutely no drivability issues (air, starting, clogging, leaking, etc.). I just changed it because I was curious to see what it looked like. I'll get a pic up soon on picturetrail. I'm no expert on these filters, but it looks as though only the bottom third was gettin' nasty. I'm going to go 8000 miles on this next one, assuming I don't run into any problems. I wish there was some sort of guage to measure restriction..I think hoot mentioned Racor makes one. JK had something going too, but haven't heard about it lately. I'll be looking into it.
Personal preference foe me is pre-oem. It's doing the filtering job, and that's what I was looking for and it can't get much easier to change.
Josh

ndamico
05-31-2003, 14:51
Amen Smitty! smile.gif

I'm glad you got 4800 miles with no problems. How large is that Racor filter?

GM Smitty
05-31-2003, 15:01
The filter media itself is 4" in diameter, and 4" in height. I always have the option to put on the larger filter also...I think it's about 1"-1 1/2" taller. I might have to make a new bracket then bacause it would hang under the frame rail. The picture of the filter I cut open is now up.
Josh

srubrn
05-31-2003, 21:54
a bear,

Yes and no on the analysis. I don't have a restriction gauge to tell you what it is when it clogs.

I took my clogged filter off and sent it to a lab where they put the filter in a machine with a known particle count and run it thru the filter and count particles on the after side. The used filter rated 97% at 2 micron.

I shouldn't but I am. If a 4in diameter by 4 1/2" filter is making it all the way to 8000 miles then it might not be doing what is supposed to. My 4.3in by about 3in 2 micron Stanadyne filter only made it to 2300 miles before it stopped up. I told ya'll I use redneck logic. If it ain't stopping up then it ain't doing it's job. Remember Racor makes our OEM filter that is not doing it's job.

GM Smitty
05-31-2003, 22:34
Todd - One of the first things I thought of is maybe the Racor isn't doing it's job after hearing how fast your 2 micron Stanadyne clogged. I haven't done any analysis, so I can't honestly say it is filtering to 2 micron. I feel like someone here had one done on a Racor unit.

However, I have talked to a few respectable and very knowledgable people who have assured me Racor makes one hell of a good fuel filter, and that's what I'm counting on. And I'm getting tired of hearing the notion that Racor can't make good filters because our OEM filter is not doing a good job. I feel it was designed to make it to 15000 miles, and that's what it does. Who knows what GM's logic was?

I'm also not predicting the filter will make it to 8000 miles. It made it to 4800 with no problems. Maybe another 300 miles and I would have noticed something...I just changed it out of curiosity.
Josh

chuntag95
05-31-2003, 23:14
Cap,
You're killing me! ROTFLOL :D I have been there (stuck under the nerf bar), but no one was home. :eek: I finally wiggled out. I think I sweat enough to act like grease and bench pressed like a %*&$ to squeeze my way out. That was the last time I force fit myself under anything.

I wonder, since GM expects the OEM filter to last 15K, if they don't already know it is not good enough. If they are looking at second filters and lift pumps, maybe one of them is reading here? Maybe the spec sheet they gave Racor for the design wasn't right? If a larger filter that has the "same" rating clogs in 1/4 the time, who's fibbing?

ndamico
06-01-2003, 00:49
The big CAT filter is 11" x 4". The small one is 7" long.

srubrn - Where did you send your filter to get it tested?

Does anyone know of any lab's that provide this service?

srubrn
06-01-2003, 08:05
I sent it back to Stanadyne. I befriended a engineer there and he did it for me. I know what some of you are going to say. The results could be bad due to Stan. doing the testing. Beleive me they are not. If you only knew what I am not telling, then you would know. That story would take too many pages to type. I would take a phone call. Anyway I am very happy with the filter set-up and I know it does its job.

Forced Induction
06-02-2003, 06:26
I have been reading alot of posts regarding pre and post filter setups, and am not even sure which way I want to go yet but here is another idea that may (probably) have been mentioned in another thread that I did not read yet.
If we install a large(similar to long CAT) 2 micron filter pre-oem we change it at ~10-15k, and seem to also change the oem (which should be clear anyway) but whatever. Now the oem alone which is supposedly 10 micron, will last 10-15k and it is short, will no pre filter. Now what if we installed a large 10 micron filter and a large 2 micron filter pre-oem?? It would stand to reason that the large pre-oem 10mic would last atleast twice as long as the oem and since now the 2mic is getting most of the large particles filtered out early that filter should also last twice as long, and the oem filter should theoretically never clog.
The only problem with this set-up that I see would be the added pressure drop with two filters. But according to cat with a 2mic and 15 mic filter the pressure drop would be less than 1psi. I did not find a cat 10 micron filter yet, only a 15.
Like I said earlier, this was probably posted earlier and if it was I apologize for being repetative. It just seems like a decent idea. The large cat filters are only about $12 each and should be able to get close to 30k before changes. Of course I and many probably would never go that long but it would be a good experiment to see if you could. smile.gif
Just another crazy fuel filter idea. I figure there's so many out there, this will just blend in anyway. :D

Have a great day guys, and happy filtering!! smile.gif :D

J

Captain Mal
06-02-2003, 08:19
Forced,

You just gave me an idea. Remove the factory filter. It doesn't work anyway. Drill a couple of small holes into the bed and mount a series of CAT filter assemblies along the front of the inside bed. A small lift pump could be added into the fuel line to help prime them (at least 3 filters in series) and then just re-connect the line to the engine.

If the in-bed location is not a good idea you could mount the bank of filters in the cab, inside a light bar on the roof, inside some kind of 'ram-air' hood scoop etc.

Actually, the issues you address are correct and desirable. The problem is kinda like real- estate...location, location, location.

Wait! Has anyone thought of replacing the factory filter with a better/larger one?

"...still crazy after all these years"

Jelisfc
06-02-2003, 08:24
Forced Induction, It's all about volume. A 2 micron sphere has a volume of 4.2, a 5 mic is 65.4, and a 10 mic is 523.6. If you run a 2 micron absolute pre filter I'd bet you could easily get 100K miles out of a OEM filter. I have a spreadsheet that further outlines this if anyone cares.

hoot
06-02-2003, 08:42
Racor sells vacuum sensors and dash mount monitors.
web page (http://www.parker.com/parkersql/default.asp?type=2&id=27)

[ 06-02-2003, 11:23 AM: Message edited by: hoot ]

56Nomad
06-02-2003, 10:21
Racor claims it's 2 micron is 95% effiecient.
hoot..... I assume you are speaking of the OEM filter? Not our secondary 2 micron Racors?

Kleve
06-02-2003, 10:52
Captain Mal

Your comment on replacing the factory fuel filter with a better/larger one makes absolute sense. Guess no one makes one yet? Have never seen that option discussed here that I can recall...

Kleve

hoot
06-02-2003, 11:20
Nomad..... I edited and deleted some previous posts..

Racor rep says....

The 2 micron filters Nomad and I are using are...

Racor Diesel Spin-On 600 Series
Based on #2 diesel fuel,
88% efficient at 2 microns.
98% at 4 microns.

The fellow told me that Isuzu spec'd the OEM filter for Racor to build, based on very clean fuel. The rep specifically said this was a mistake on Isuzu's part.

He also said the only reason Racor does not recommend using a 2 micron post OEM is for flow reasons. He said the larger filter you use if you do go post, the better. When I told him I was using the 90 size canister he was surprised we found room for it and reiterated that as long as you go as long as you need to without restriction it should be fine.

Another point he brought up was the plastic internal design of the OEM filter was Isuzu's spec. He did say some problems occured where the plastic slides (spins) within the housing making OEM filter removal almost impossible without removing the assy and doing it on a bench. I think I heard of this one time.

He bragged about their head (600 Series) having all the ports available for different installation locations and the ability to add a bleeder valve to the top port.

[ 06-02-2003, 11:28 AM: Message edited by: hoot ]

felpa41
06-03-2003, 19:58
My local Chevrolet diesel mechanic (Bruce) at Miller Starnes Chevy/Buick told me today that GM is now telling the mechanics to change the OEM fuel filters every 5,000 miles.

He liked the idea of my big Mega Filter installation.