What is a rebuilt Injection Pump????

[orrum]

In the interest of attempting to turn me from a worthless cowboy into a fair to middling GM diesel cowboy what the heck is meant by rebuilding a IP???? Is it just replacing the seals, cleaning it up and setting it??? I read about the clearances getting wide due to wear and the two cycle or motor oil not only lubricates it but helps fill the void so to speak with its thickening of the fuel. I intend against a lot of folks advice to run my truck on a single tank no heat WVO blend and my IP is going to fail according to some folks. I have no idea how many miles r on my IP, got 295000 on the truck so with my luck I already have a hi mileage IP and its gonna go down fast so I am curious about my options when that happens? New IP and cost? Rebuilt IP and cost? Used IP and cost? Then there are several differnet DB2 IPs, so which should I get? No such thing as to much info. Should I go ahead and get a IP and have it on hand? How much does it cost to get a IP switched out or am I capable of doing it myself? I have all the parts now to finish setting the truck up to run on WVO and as soon as I get the filters installed I am gonna do it!!!! Thanks again for all yalls help. :agreed::rolleyes5:

 

[schiker]

I guess it depends on the rebuilder and core condition. There is a bearing and several items that wear. The clearances and surface finish quality are demanding. Bison has a thread on the mechanical parts and I have one with lots of pics of an IP parts and pieces on a DS IP. I would expect more than a cleaning and seal replacement unless its just old age and gummed up.

 

[schiker]

http://www.thetruckstop.us/forum/showthread.php?21893-DS4-IP-rebuild-time(mechanical-aspect-only)

 

[Koots]

I bought a used DB2831-5079 pump from a military 6.5TD HMMWV and a seal kit for just under $200 CAD (with shipping), so far i've found that both the driveshaft and the housing itself were corroded to the point of utter uselessness, so i swapped it all over to my OEM c-code housing using the old driveshaft.

It works (so far) but i ended up ruining all the o-ring seals for the hydraulic head to pump body and had to wait for 10 days for a pack of 10 to fly in from Mississippi (Mylex Int. came through with good customer service and great help). Of course the first one out of the pack does the trick and the pump is back in the truck. This was not the most ideal situation (ended up taking WAAAAAAAAAYYYYYY too long) but i did learn a lot about these pumps and i can take em apart and reseal one in about an hour now. I used the military manuals guide on how to take the pump apart (should be available online somewhere around here LOL). It was blunt and helpful, but i was reading it off of an old laptop and was trying not to make it too greasy.

I'm hoping that this pump is gonna do okay. It sounds good but it's had a total of 5 minutes runtime so far, mostly due to the hole that developed in my trans cooler line while it was running. I ended up covering my parents driveway in trans fluid because the line somehow shifted and moved into the torque converter (no dustshield right now) and wore a hole into it.

Even with the pump turned down 1/6 from 200HP stock specs, this pump is throwing out plenty more fuel than the old one was (stock c-code with one refresh in it's life long before i owned it). Starts up like a champ with just a little touch of throttle, the truck has always required 1/2 pedal to start unless it was nice and warm and just turned off and turned back on again. So far it seems like i ddidn't waste my money but i certainly wasted a lot of precious time.

Can't offer you any more advice than that LOL I'm not a journeymen mechanic but a trained mechanic, most of my experience is just maintaining my own vehicles and those of my friends and family. So i'm basically an edumacated backyard mechanic in skill level.

 

[orrum]

Thanks fellows 4 the info but read Bisons thread on rebuilding a IP. Think I not gonna try that but still like to know about switching one out, any threads on that?

 

[Missy Good Wench]

The rebuilding, setting and such of the IP, although not a really tough job,takes some specialized tools to do it right.

The advance piston wears in its bore in the housing to the point that it will not work correctly.
The repair entails reaming out the bore and installing an oversized piston or sleaving the hole.

I am not sure exactly what they do but the advance piston area is one that gets tended to.
The head and rotor are of major concern. If the clearances get excessive the pump can't produce the needed fuel pressure to inject fuel.

In the case of a worn out head/rotor, replacement is the only option.

Bearings and seals are the other main items.

The shut off solenoid as well as the cold case advance solenoid may be replaced too.

Once the parts are replaced and things are adjusted the pump is installed on a test stand where it is run at varying speeds and tested for proper opperation.

My suggestion is to leave all but minor servicing to the guys that have the tools to do it.

I have replaced shut off solenoids and replaced a few throtle shaft seals on some DB2 pumps but thats about as far as I would go with it.

Missy

 

[Acesneights1]

I actually got to test a few pumps on an ancient test bench they had at SUNY Farmindale. It had the test tubes and you ran the pump for a certain # of cycles and it filled the graduated cyls and you measured them. I don't think they use those anymore but i was quite interesting.