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dieseldummy
06-05-2006, 20:26
The Stanadyne mechanical injections pumps can be a stretch of the mind at times. Other times they are so simple it's unbelievable. Here's where I'm at right now: I've disassembled a couple of pumps and have come up with a few thoughts.

Before I get to the thoughts I'll share how to tear a DB2 down.

For starters clean the pumps exterior up to prevent contamination of the insides. Next, remove the top cover, throttle guide stud, throttle linkage, gov. linkage from the rack control, and finally the rack control.
http://www.thedieselpageforums.com/photopost/data/500/medium/gov_assy_guide_stud_fuel_control_lever.JPG

You will then remove the to bolts at 10 o'clock and 2 o'clock. They have a 1/2" head.
http://www.thedieselpageforums.com/photopost/data/500/medium/side_view.JPG

http://www.thedieselpageforums.com/photopost/data/500/medium/other_side_view.JPG

On the bottom side of the pump is an allan head bolt that needs to be removed. It is 5/16" and sets just infront of the advance piston.
http://www.thedieselpageforums.com/photopost/data/500/medium/allan_head_bottom_of_pump.JPG

Once all of these things are removed you can remove the head assembly from the main housing. When ever removing the head assy make sure that the outlets for the injector lines are pointing downward or you will be picking pieces up off the floor. I like to put the head in a vise and gently work the housing off of it. A rubber mallet will come in handy if used gently.

After the housing is off of the head assy it will look like this:
http://www.thedieselpageforums.com/photopost/data/500/medium/inside_housing_camring.JPG

What you are looking at is the main shaft and the camring.

The head/rotor will look like this with the fuel metering leaf spring and rollers installed:
http://www.thedieselpageforums.com/photopost/data/500/medium/head_rotor_top_view.JPG

This is what it will look like with the leaf spring, rollers, and plungers removed:
http://www.thedieselpageforums.com/photopost/data/500/medium/head_rotor_top_empty.JPG

To take the rollers and plungers out of the rotor all you need to do is remove the fuel metering screw and spring. Once that is done the rollers and guides will slide out and the plungers will slide out of the rotor.

dieseldummy
06-05-2006, 20:53
This is what the plungers, leaf spring, and rollers look like: (from top to bottom in that order)
http://www.thedieselpageforums.com/photopost/data/500/medium/plungers_rollers_leaf_spring.JPG

To remove the rotor from the head the transfer pump must be disassembled. To do this there is a allan head bolt at the top side of the head that holds the nose cone in place that need removed. After it's gone the nose cone unthreads and exposed the internals of the transfer pump. The internals slide right out, just be very very careful or the springloaded vanes will scatter. The rotor will slide right out now.

The pump pictured is a heavy duty 6.2 model. The main difference in 6.2 pumps is the calibration like timing advance, fuel rate, and ect. The difference between 6.2 pumps and 6.5 pumps is calibration along with bigger plungers. (.31" vs .29") I've been told that Stanadyne makes a pump that makes use of .33" plungers and that is what constitutes a "marine" pump. A good way to tell what size plungers a pump has is by the model number. It will start out: DB2, then next number will indicate the number of cylinders(in this case 8), the next two numbers will tell how big the plungers are (.31" or .29"). The numbers after that usually indicate how the pump is calibrated. So basicly you will have a DB2829 on a stock 6.2 an a DB2831 on a stock 6.5.

Being the tightass I am I don't/can't shell out the $1G for a "marine" pump so I am trying to make a way around it. The rollers that run on the cam ring are .38" across... I am in the process of boring out the rotor to accept these bigger plungers. The rollers have to be shortened to be the same length as the stock rollers.(.47") The problem I have run into is that all of the parts in the IP are surface hardened so the machine shop won't touch them. I do have a set of hardened set of drill bits that I can take the layer of hardening off with so now I just need a way to hone the holes out to the proper spec.

The test pump I've got setup this way was bored out using regular drill bits, a file, and some emery cloth. As you can imagine the clearances aren't quite in spec so it won't build pressure. It does however push fuel against no head pressure.

I have some other thoughts one of them being that the rotor can physicly be bored out to 7/16" if one could come up with some hardened plungers. The other thoughts will be tried to see if they are viable thoughts or not before I share them here.

Here are the questions I pose: Where does one fine a small boring/honing tool, how does a person re-apply surface hardening, and where does someone find hardend stock for plungers?

john8662
06-06-2006, 00:24
Cool Guts! Nice pictures!

Question for ya there!

When you remove the allen on the back of the head that holds the transfer pump onto the back, there are notches. Should care be taken to mark the position of these notches prior to removal? Or are these marks simple a "lock" to keep the transfer pump from becoming loose and a leak source?

Another point (that you made) in the difference in plungers and the metering leaf/screw. I'll bet the leaf used in the 6.5 pump is slighly longer to allow more travel of the plungers than the 6.2 leaf is. Just one of those parts that will get "updated" in a 6.2 pump going to 4911 specifications.

J

DA BIG ONE
06-06-2006, 01:36
DB4 (marine) figures are impressive for performance buildups on the 6.5td would be sweet.

I'm still looking into the best way to protect pumps/seals from the lowwwwwwww sulfer fuels we have to use. Mechanical pumps are IMHO best for the 6.5 but this fuel issue is sure to be a problem. Back in the early 90's I remember my MB diesel started leaking at the seals from the low sulfer crap. The seals were on worldwide backorder for MB and after being down for awhile I decided to dump the MB. I'm wondering if that is what is going to happen with our pumps too?

ronniejoe
06-06-2006, 05:26
Surface hardening is done through heat treating. Depending on the alloy in use, it could be gas carburizing, nitriding, nitrocarburizing, induction hardening or other method used to harden the surface. The only one in the above list that does not require a furnace with a chemically controlled atmosphere is induction hardening. It requires a million dollar induction machine. Machining is usually done after heat treat to retain precision tolerances.

The parts may be through hardened rather than surface hardened. This is a furnace operation.

These are not processes that are easily performed by the do-it-yourselfer.

CareyWeber
06-06-2006, 05:41
Why do all the pic just say The Diesel Page?

All the military 6.2/6.5 have hardened internals to deal with the lack of lube in JP4.

Carey

john8662
06-06-2006, 07:19
Why do all the pic just say The Diesel Page?

Simple answer. Dieseldummy ripped them off!

Just kidding, when using the "Photo Album" link above, the uploading process imbeds the TDP text onto the image to copyright the material, more, mark where the information came from. Mainly, because other forums might rip it off, and this is a deterrent.

The photo album is available for all users, and can store images to be shown in threads such as this!

J

dieseldummy
06-06-2006, 08:17
Cool Guts! Nice pictures!

Question for ya there!

When you remove the allen on the back of the head that holds the transfer pump onto the back, there are notches. Should care be taken to mark the position of these notches prior to removal? Or are these marks simple a "lock" to keep the transfer pump from becoming loose and a leak source?

Another point (that you made) in the difference in plungers and the metering leaf/screw. I'll bet the leaf used in the 6.5 pump is slighly longer to allow more travel of the plungers than the 6.2 leaf is. Just one of those parts that will get "updated" in a 6.2 pump going to 4911 specifications.

J

I never thought about marking the nose cone. I highy suspect that it doesn't matter because it needs to be tight to ensure that it doesn't leak. The leaf from my 6.5 pump is the same as the late model 6.2 pump. The early model is .5 mm shorter.

What can I do to get the pictures to show again there MR MOD? They all worked last night... I can link them to a picture hosting sight if necesary.

dieseldummy
06-06-2006, 08:21
DB4 (marine) figures are impressive for performance buildups on the 6.5td would be sweet.

I'm still looking into the best way to protect pumps/seals from the lowwwwwwww sulfer fuels we have to use. Mechanical pumps are IMHO best for the 6.5 but this fuel issue is sure to be a problem. Back in the early 90's I remember my MB diesel started leaking at the seals from the low sulfer crap. The seals were on worldwide backorder for MB and after being down for awhile I decided to dump the MB. I'm wondering if that is what is going to happen with our pumps too?

DB4 would be optimum for performance... The best thing to do with these pumps is run a lube additive. All of the seals are o-rings, so if they are kept wet it shouldn't be a big deal short of loosing tolerances.

dieseldummy
06-06-2006, 08:24
Surface hardening is done through heat treating. Depending on the alloy in use, it could be gas carburizing, nitriding, nitrocarburizing, induction hardening or other method used to harden the surface. The only one in the above list that does not require a furnace with a chemically controlled atmosphere is induction hardening. It requires a million dollar induction machine. Machining is usually done after heat treat to retain precision tolerances.

The parts may be through hardened rather than surface hardened. This is a furnace operation.

These are not processes that are easily performed by the do-it-yourselfer.

This is what I was affraid of... I thought that maybe a simple heat tempering process may help, but most likely not. I've heard of shops nitriding crankshafts, suppose they would do IP parts?

ronniejoe
06-06-2006, 08:34
...suppose they would do IP parts?

Depends on the alloy. The heat treatment process is tailored to the particular material being hardened.

For instance, most of the gears in our trucks are made from 8620 steel. These are hardened by carburizing, which diffuses addtional carbon into the surface and freezes the solution through quenching. Nitriding will not work.

On the other hand, nitrided materials, such as 4340 steel, are already high in carbon. Nitriding diffuses nitrogen in to the surface altering the chemistry of the part forming nitrides of carbon.

An induction hardened material is also high in carbon content to start with. The heating process forces a phase change and alters the arrangement and structure of the carbon atoms in the surface, then freezes them in place with a quench.

Each process is specifically engineered for each material and offers advantages and disadvantages.

moondoggie
06-06-2006, 08:47
Good Day!

A question from someone that knows very close to nothing about IP internals: Weren't some of the parts changed to ceramic to make them last longer in low-sulfur applications (which soon will be all of us)?

Blessings!

john8662
06-06-2006, 09:27
What can I do to get the pictures to show again there MR MOD? They all worked last night... I can link them to a picture hosting sight if necesary.

Not necessary, all pictures you're posting work perfectly, the question by the other member was why they're marked The Diesel Page on the lower right hand corner.

The images used in the Photo Album are ONLY for TDP members, and can't be viewed off site. Meaning, once you've logged into the forum (gotten the forum cookie with date stamp and authentication) you can also view images or have permission to view any images in the photo album.

Some have had problems (me) that had the forum bookmarked via the IP address (number, not Injection Pump for our discussion) that was originally linked to. The domain name for the forum is the preferred method, using thedieselpageforums... So, if your bookmarks still reflect an IP address to access the forums, you'll have problems logging into and seeing the images in the photo album, because to your browser (and cookies) they are two completly different sites. When, they are really one...

You did good Dieseldummy!

J

DmaxMaverick
06-06-2006, 12:55
Great thread!



What can I do to get the pictures to show again there MR MOD? They all worked last night... I can link them to a picture hosting sight if necesary.
What do you mean? If you are trying to attach an image in a post that's already in the thread, that has been disabled. This prevents images from showing up in replies and quotes, etc. This increases bandwidth (not an issue for us), and makes it very frustrating for dial-up users. If needed, we can change this setting. It seemed prudent at the time. Hosting the image elsewhere won't change the way it works, it's a BB setting, not a picture hosting thing. If necessary, you can upload the same image with a different file name, but that's up to you. If they are just not showing up after they were there before, John is probably right. We had some users with the same complaint, and correcting the URL seemed to fix that. The correct link to The Diesel Page Forums is: www.thedieselpageforums.com/tdpforum .

About the watermark (copyright image)....
It prevents other websites and individuals from snagging images without showing proper ownership. If you want your own mark, just put it in a place other than the lower/right corner. The watermark is automatically embedded by the photo album software. In accordance with TDP copyright policy, any content and attachments posted here is copyright TDP. It's still your stuff, it's just a protection against "public domain", which is very misunderstood (and abused) throughout the web. All this is to protect TDP, and the users. If you have any questions/concerns, don't hesitate to ask. DM

dieseldummy
06-06-2006, 17:24
Thanks for the explaination on various hardening processes RJ!

John and DM,
The problem is that sometimes when I'm logged in instead of the image showing it just shows a white spare that says: www.thedieselpage.com It's working good now.


Back to the subject at hand. I talked to the machine shop today and since I can take the surface hardening off they can bore it out however I want. The only problem is that with no hardening it will be a limited run time performance only pump...

Justin

gmctd
06-06-2006, 18:36
FYI -the (hardened) plunger bores will require micro-honing to match each new plunger - necessitated to achieve the extremely close-tolerance fit whuch allows the fuel to become the pumping seal.

That is how the IP can pump 1700psi and up without sealing rings.

Same applies to the rotor-head tolerances - no sealing rings, there.

Oem plungers are matched to each bore, and the rotor is matched to each head, which is why a rebuild is so expensive - you get matched plungers to rotor to head, about 330 bucks @cost 4yrs ago.

The precaution is to keep each plunger in it's respective bore during installation - the plungers generally cannot be swapped between bores.

Nor can rotors be swapped between heads.

If comparing the DB2 series camring to the DS4 camring. the DS4 ramps are barely perceptible, which reduced the mechanical pumping vibration\clash, while allowing greater output for the 6.5 and (proposed) IH 7.3.

Reliability and longevity were improved, as a result

BTW - the DB2 7.3 and 6.5 camrings could not be reversed, whereas the 6.2 camrings could be reversed to fit in the cw or the ccw pumps.

As you may recall, I rebuilt a 6.2 DB2, a DB2-4911 and a DS4-5288 several years back.

Bobbie Martin
06-06-2006, 18:48
I've been told that Stanadyne makes a pump that makes use of .33" plungers and that is what constitutes a "marine" pump.

This is correct, the "Marine" pump uses .330" plungers. The Stanadyne number is DB2833 4974. This is the pump I have in our Suburban and the same one Peninsular sells.

dieseldummy
06-19-2006, 20:02
Well, here's some more pics and thoughts:

http://www.thedieselpageforums.com/photopost/data/500/medium/DSCF1432.JPG

The head/rotor on the left is a DB2 from a 6.2 w/my supersized plungers in it. The one on the right is a DS4 from a '94 (5067) w/no plungers. If the rotor from a DS4 could be swaped into a DB2 head the fuel output would be awsome. Too bad it won't work... It would be great if they did swap since DS4's are a dime/dozen, DB4's are high $$$.

One thing that is being looked into is more stroke vs. bigger bore. I'm waiting to fix some deeper problems with the testbed truck before testing can continue. If the new idea works it will be cheap... Like labor to take of the pump and tearing down the pump.

A big thanks go out to John for helping with this project! It wouldn't have come along this far without his input and parts.

Also looking into a HO DS4... If time permits. Stay tuned.

CareyWeber
06-20-2006, 14:53
Not necessary, all pictures you're posting work perfectly, the question by the other member was why they're marked The Diesel Page on the lower right hand corner.

The images used in the Photo Album are ONLY for TDP members, and can't be viewed off site. Meaning, once you've logged into the forum (gotten the forum cookie with date stamp and authentication) you can also view images or have permission to view any images in the photo album.

Some have had problems (me) that had the forum bookmarked via the IP address (number, not Injection Pump for our discussion) that was originally linked to. The domain name for the forum is the preferred method, using thedieselpageforums... So, if your bookmarks still reflect an IP address to access the forums, you'll have problems logging into and seeing the images in the photo album, because to your browser (and cookies) they are two completly different sites. When, they are really one...

You did good Dieseldummy!

J

John,

This all I see a white block that says www.thedieselpage.com (http://www.thedieselpage.com) (and no the pic is not a link to a photo albumn) but no injection pump pics.

Carey

DmaxMaverick
06-20-2006, 15:22
Carey

Email or PM me. Something's amiss with your system's settings.

The www.the...... image is the replacement image for hijackers (bandwidth theives). You shouldn't be seeing it unless your settings are off, or have a utility running that blocks certain URL formats. Easy to fix.

KallyI
06-20-2006, 16:00
John,

This all I see a white block that says www.thedieselpage.com (http://www.thedieselpage.com) (and no the pic is not a link to a photo albumn) but no injection pump pics.

Carey

That's all I get as well. A couple of days ago, I was able to see the pictures, but not now???:confused:

DmaxMaverick
06-20-2006, 16:30
I'm not yet sure what's happening with the images. As mentioned before, be sure your URL (address of the page you are viewing) is www.thedieselpageforums.com/tdpforum , and not 72.22.76.69/tdpforum. I've checked all the settings and everything is correct. Nothing related has been changed in several weeks.

If anyone still has issues with this, please email me at dmaxmaverick@thedieselpage.com . I need to know how many are having problems, and if there is a common ground.

Just a few minutes ago, I created a new registration (just like anyone else would) on a separate machine that barely has enough features to get online. I can view the page and images with default security settings.

Once again, please email me if you are having any issue viewing images.

CareyWeber
06-21-2006, 19:09
I'm not yet sure what's happening with the images. As mentioned before, be sure your URL (address of the page you are viewing) is www.thedieselpageforums.com/tdpforum (http://www.thedieselpageforums.com/tdpforum) , and not 72.22.76.69/tdpforum. I've checked all the settings and everything is correct. Nothing related has been changed in several weeks.

If anyone still has issues with this, please email me at dmaxmaverick@thedieselpage.com . I need to know how many are having problems, and if there is a common ground.

Just a few minutes ago, I created a new registration (just like anyone else would) on a separate machine that barely has enough features to get online. I can view the page and images with default security settings.

Once again, please email me if you are having any issue viewing images.

DmaxMaverick,

I had the site in my favorites withe the IP addy rather than the URL.

Thanks

Carey

DmaxMaverick
06-21-2006, 19:53
Very good!

I'll give this a couple days to be viewed, then delete all this off topic mumbo-jumbo. It's not nice to hijack a thread, and I'm as guilty as anyone in that regard.

Future BB issue questions should be posted in the Website Updates & Announcements (http://www.thedieselpageforums.com/tdpforum/forumdisplay.php?f=20) or Members (http://www.thedieselpageforums.com/tdpforum/forumdisplay.php?f=16) forums.

elco
04-16-2008, 06:16
Did you finish the pump and did it work ?