Diesel Place banner

1 - 5 of 5 Posts

·
Registered
Joined
·
177 Posts
Discussion Starter #1
I've been having hard starts, loads of white smoke (mostly on startup), nasty fumage while driving, etc.. The local diesel shop of repute (Statline Diesel Service in Edwardsburg, MI) tells me that I've got way too much return flow coming out of the IP, and that it needs to be rebuilt (Injectors were bad too, so I'm getting them done also). So I just pulled the injector pump off my truck ('82 6.2L Chevy C20). But the nameplate on the IP says "International Fuel Systems, remanufactured" (m/n 4502). So I'm wondering: would it be worth the extra $$ to get it swapped for a rebuilt Stanadyne IP at the local shop/Stanadyne dealer ($500/1 yr warranty; Stateline Diesel), or would I be just as well off sending it up to Accurate Diesel in MI to have the unit rebuilt and returned ($225/6 mo. warranty), presumably with the same housing/nameplate/etc, but with new & updated guts?

Its a project truck that doesnt get a whole lot of use; mainly just when I wanna haul some stuff or I just want to throw my gear in the back and go somewhere. I'm semi-mindful of what would impact the potential "classic car" value, but restoration is WAY far off... (the electrical system & interior are a mess, and then theres plenty of body rust too)


Thanks,
-Scot
 

·
Registered
Joined
·
2,991 Posts
High return fuel and white smoke means your advance piston is worn out, and likely a lot of other parts inside the pump. IFS was a big IP rebuilder, but they were not Stanadyne authorized. If you take it to an authorized shop, they 'should' replace the nameplate with a Stanadyne one. Personally I hate seeing IFS rebuilt pumps come in, for one, I know I have to make a new nameplate and come up with a serial number because theirs are useless, but mostly because they were notorious for using aftermarket and homeade parts inside. The worst is undersized advance pistons, they actually turned down standard advance pistons and put a sleeve in the advance piston bore. What the problem with that you ask? Well, how am I going to replace an advance piston when I can't ream it out to a standard size? The answer is that I have to replace the housing and put a new piston in.

If you can get an exhange pump that would be my suggestion. I don't have any faith rebuilders who claim to 'rebuild' DB2 automotive pumps for under $500. If they are, then they're not replacing parts they should be replacing. I could name just the parts that I personally replace everytime and the price would be about $400. You get what you pay for, Injection pumps aren't water pumps, they are quite a bit more complex inside than most people realize.
 

·
Registered
Joined
·
177 Posts
Discussion Starter #4
The leakage around the advance piston matches the explanation the guy gave me at Stateline. I really scratched my head, though, when he told me that the IPs were designed with steel pistons in an aluminum housing... being a mechanical engineer I thought that sounded goofy; you'd want to make the part that's easiest to replace out of the material that's most likely to wear, ie. aluminum piston in a steel housing, or at least a steel sleeve if the housing is an aluminum casting. Did they change/fix this in the later updates to the IPs?

Also, if I get an exchange pump, would I have to worry about the timing marks on the new pump housing not matching the engine that I've got? I read somewhere in some other posts on this forum that that is of some importance, but couldnt tell if it would be objectionable to use a different housing. I suppose the worst that'd happen is that I'd have to wiggle it around the timing mark some (ie. fidget with the timing) until it sounds good? How far can it be off the block timing mark until I start running into EGT problems?

Lastly, if I send in a DB2-4502 and it gets updated to the latest & greatest, does that mean that I'm getting back a DB2-4502, or does it come back reincarnated as a DB2-4544 or whatever? (ie. like software upgrades from "version 3.0" to "version 4.0"?
 

·
Registered
Joined
·
2,991 Posts
If a pump model is superceded, like say 4509 supercedes to 4723, its because there was a considerable number of parts changes and/or an update to the calibration specs. Even if your pump doesn't supercede to a later model, there will almost definitely be parts updates that you may or may not have yet depending on when your pump was built or last rebuilt.

As far as your ideas on the steel sleeve, I understand where your thought is, but consider this, even steel to steel will wear out, they (Stanadyne) does use this setup in DS and DB4 pumps, but the difference is that the sleeve is not serviceable, so once it wears out, you have to replace the housing and the advance piston. With steel piston on aluminum housing, all you have to do is ream it Oversize and replace the piston. Advance pistons are available from Stanadyne in STD, +2, +5, +8 and +12 thou oversize.
 
1 - 5 of 5 Posts
Top