2H has oily glow plugs

[torfab]

This car is new to me, and I'm hoping to get the engine worked out to use it in a project. I may end up rebuilding it, but it runs great when warm so I'm staying optimistic.

The glow plugs have an oily coat when removed. I ran a compression test, and the tester gets oil on the tip after removed as well. I got a 300-400 psi compression in cylinder 1, but the gauge must have oil in it from testing because now it won't give me a reading anymore, not even in cylinder 1 again.

The engine smokes when fired up, and is hard to start due to several glow plugs not working. When it gets hot, it runs really nice and doesn't smoke (unless I'm accelerating). It starts up in 2 seconds after it's already hot, and doesn't smoke.

Since the combustion happens from the precups, and any oil in there should burn away, then I'm curious why it's still on the glow plugs when removed.

I'm not opposed for a complete rebuild, but hopefully someone here has a theory or two for me to ponder?

 

[roscoFJ73]

Its probably leaking down from the valve guide seals. Engines with this problem usually make a bit of smoke when taking off from the lights from the oil that has dripped down.

 

[torfab]

that somewhat makes sense, except the valves are lower than the glow plug and injector, and separated by the precups, right? If this is the answer, and I don't need to do rings, then I'm happy. The head will be pulled after an FJ40 and FJ60 engine swap is finished in the garage.

 

[Tapage]

oil rings .. ?

 

[torfab]

The oil rings is my number one theory, but I'm hoping to try eliminating any other issues first.

 

[Radd Cruisers]

Some oil on the glow plugs is quite common. Don't go looking for things that aren't necessarily a problem and make them in to one.

They protrude into the combustion chamber and are well away from the valve guide seals (which don't leak all that often).


~John

 

[Jan-78FJ40]

I find some oil on the glowplugs of my 2H every time I look. It does not affect compression, performance or starting, so I ignore it.
cheers,
J

 

[torfab]

After some research, I believe the problem is caused by unburned diesel. I don't think the fuel is atomizing, so either the IP is weak or the injectors are not built to spec.

My injectors were rebuilt a year ago, so I assume it's the IP. I will need to have them pop tested and then bench test the IP...

 

[DieselFumes]

Is there something wrong with how the truck drives? Or is this something you have noticed and are trying to prevent any future problems? Or when you swap are you looking to address any issues while into it?
My truck (358km 2H unknown rebuild? but motor has some writing on valve cover which leads me to believe something has been done) will (rare) sometimes smoke on start and sometimes not cold.... always runs better when warm, never has problems starting, If I were to swap this motor into something else (which I don't l=plan on) I think I would only replace gaskets, even though there are no dripping leaks... my 2 cents

 

[Jan-78FJ40]

After some research, I believe the problem is caused by unburned diesel. I don't think the fuel is atomizing, so either the IP is weak or the injectors are not built to spec.

My injectors were rebuilt a year ago, so I assume it's the IP. I will need to have them pop tested and then bench test the IP...

I considered that in my case also, and put in brand new injectors. I have not pulled the glow plugs since, so I don't know.
Honestly, I'd be surprised if an injection pump that is that weak would not affect drivability a lot.
cheers,
J

 

[torfab]

Is there something wrong with how the truck drives? Or is this something you have noticed and are trying to prevent any future problems? Or when you swap are you looking to address any issues while into it?
My truck (358km 2H unknown rebuild? but motor has some writing on valve cover which leads me to believe something has been done) will (rare) sometimes smoke on start and sometimes not cold.... always runs better when warm, never has problems starting, If I were to swap this motor into something else (which I don't l=plan on) I think I would only replace gaskets, even though there are no dripping leaks... my 2 cents

Yes - I'm trying to address any leaks and problems while I pull the engine. I'll be replacing all the seals, and checking all the specs. I know these engines run for a long time, but I want it to continue that reliably once I'm done with the project. This bothers me a little, and I want to make sure it's not a major issue before proceeding. I've been told a hundred times that this isn't a big deal, but I won't believe it until I see it with my own eyes.

I'm planning on replacing the head gasket, and resurfacing the head, so that should shine light on the condition of the rings, inserts, precups, and excess carbon in the cylinders.

 

[DieselFumes]

Ah ok- makes sense to me too.

Actually since you'll be that far into it why not do the bottom end while its out? Not necessarily a bore it out but fresh bearings, pump, rings...

-2 cents-