Smoky old IP

[jettaman8691]

Recently picked up a 1981 Rabbit pickup that had been sitting for at least three years. PO had run homemade biofuel of questionable quality, but at least it had been running when they parked it.
The truck wants to run, but only when I pull fuel through the IP manually. The engine shuts down when the IP runs empty because it is not pulling fuel in. And the smoke is thick and white, which I am assuming means a gross amount of fuel is being pushed into the engine, resulting in most not combusting.
When I pulled the injectors, three of them had a lot of unburned fuel around the bases. Only one hole was dry. The injectors are in for a re-build right now.
I am taking a guess that the IP needs a re-seal job, since it doesn't hold a prime and produces massive white smoke. Would that be a somewhat intelligent guess?

[TylerDurden]

AIUI, an IP that can't draw fuel has stuck vanes in the lift section. That also means it will not develop sufficient internal pressure to provide dynamic advance and also to prevent fuel cavitation.

That means it will allow bubbles into the high pressure section, delaying start of injection, as evidenced by the grey/white smoke. (Excessive fuel would be dark sooty smoke.)

The IP will need resealing, but also definitely needs the vanes loosened either by using solvents or re-assembly.

[82vdub]

I agree with Tylerdurden's analysis. You may be able to install a low PSI pusher pump to push fuel to the IP, but that may only be a temporary resolution, and may never get it to run any better. Jack, the owner of this forum, sells rebuilt IP's. They are like $500, so that may be a good route to go to get past your IP issue. Have you run a compression check to see how good the internals are for the motor? You may want to do that before spending too much $ on the car. No amount of injector or IP work can fix rings that won't ever seal, if you get my theory here.

[jettaman8691]

Thank you very much folks, for the excellent suggestions. I am looking for a spare IP somewhere in my pile of parts to replace the one in the rig. May not be the best, but might run better. Can't swing spending the funds right now for a properly running IP. I need to check out the compression, yes. The rig has 'only' 170K or so miles, so should be okay; it was used regularly before it was parked.
It is the 'LX' model and came with an air conditioner, of all things. An air conditioner on one of these little pickups? Thankfully it is disconnected. It does have a more modern hydraulic motor and not the mechanical found in most older vdubs, so might be worth keeping around.

I think the reason it sat so long was that the interns on the organic farm where it was just didn't want to trouble themselves with the regular maintenance and peculiarities of running these old diesels, A lot easier to just jump into the ol' gasser, fill 'er up, and get on with the day.

This is truck #2, so am going to sell one of these as soon as possible.

BTW, that TylerDurden moniker; I frequent a site called zerohedge.com that uses the same. Any connection?

[TylerDurden]

I am unaware of any such connection... nor would I be disposed to discuss such connection, if it did in fact exist.

[sgnimj96]

If you have the time, tools, and patience... clean and reseal it. Gunk and dirt that gets in or forms inside the IP can never really get out unless the pump is dissassembled. Outlet has screen so the tiny hole doesn't clog.
Neat video of the parts inside https://www.youtube.com/watch?v=QwVTm2-W-JE

[jettaman8691]

Well darn, this motor has other problems. The intermediate shaft will not turn freely; in fact, I have to use a ratchet to turn it! There are probably other things going on in this thin that I haven't found yet, so unless someone else wants a project, this little pickup is going to the wrecker. Don't have the time nor the funds to get into a complete rebuild right now. Darn.

[82vdub]

Well darn, this motor has other problems. The intermediate shaft will not turn freely

Unless you disconnected the oil pump and vacuum pump, I would expect the intermediate shaft to not spin freely. Both the oil pump and vacuum pump are spun by the intermediate shaft.

[TylerDurden]

I wouldn't scrap it just yet!

Take 15 min and check around...
Pull out the vacuum pump and try the IM shaft again. If it spins by hand, check the vacuum pump. If the vacuum pump turns by hand, put a socket & extension down the VP hole and see if the oil pump turns by hand.

Wish I were closer.

[jettaman8691]

Bingo, home run, and a big 'ol New England Patriots interception save! Good job people, and thank you for your continued observations and input on this forum.