has this ever happened to u???

[lawny]

car: 81 gld

scenario: driving car at 100k's on the hume, all of a sudden the rev's started going up all on there own even when i took my foot off the pedal, smoke pissing out of the exhaust, probably due to it revving its tits off. i had to turn the key off for it to stop revving. i thought the accelerator cable was just stuck, but the revs were going up and up. started the engine again and it idled fine but then as soon as i pressed the accelerator it went up again on its own. a couple of starts later it didnt do it again and i drove it home

any ideas what the hell happened?????

[FJ Steve]

to answer your first question. No.

[Preen59]

Could be a blowby problem. Because it's a diesel it can run on its own blowby gas if there is enough oil and fuel in it. Next time it does it get out and squeeze the crank case vent hose shut. If the revs drop back down, you've found your problem. I'd suggest changing the oil (because it could be heavily diluted with diesel) if this is the case if you haven't recently to start. After that it's probably time some some new pistons and rings, but let the Mk1 diesel guru's chime in on that one..

[oracle1]

Your Burning oil

I agree your burning oil or excess fuel somehow, the question is where is it coming from, pull of the crank vent and see how much blowby is coming out at idle. It may have got a dollop of oil down its snot that has been lying around somewhere in the intake system. Id get to the bottom of it quick, or the thing could go bang in front of you. The fact that it turned itself off with the key seems to indicate that the fuel pump is still in control, what color was the smoke black or white? I am assuming there isn't a turbo? The fact it behaved itself at idle and then revved when you gave it more fuel also makes me wonder about the fuel pump. The fuel pump is still unfamiliar to me gldgti or mullins need to chime in

[lawny]

there is no turbo and the smoke was black i think

[oracle1]

Ok my guess is?

Sounds like its getting to much fuel for some reason, without out it being in front of me its hard to tell, when gldgti logs in again he may be able to tell you more about the pump. To much fuel sounds like the problem the question is how? Whats the history of the fuel pump how many K's has the engine done?

[lawny]

Sounds like its getting to much fuel for some reason, without out it being in front of me its hard to tell, when gldgti logs in again he may be able to tell you more about the pump. To much fuel sounds like the problem the question is how? Whats the history of the fuel pump how many K's has the engine done?

not sure on the history of the fuel pump and the engine has done 260,000. before i had purchased it an old guy owned it and hadnt driven it over 75kph for 15 years. this was the first time in a long time it has gone 100kph.

[oracle1]

It may just need a good run however?

It may be just a little sticky somewhere or it could be more serious. Without doing more research on the pump and knowing how the electric fuel shutoff works, and where/how the excess fuel could be entering the system I would be wary of the engine running away.

If the electric cutoff doesn't stop the fuel you have a problem. Lets hear what gldgti or the other die/heads have to say and I say that with the utmost respect of course? I don"t have enough experience with this type of pump.

[lawny]

cheers so far though. lets see what he rest have to say.

[Jarred]

Interesting. I've never had it happen to me at all.

If it was a blow-by/run-on issue, I believe you would have had issues getting the engine to stop.

Logically thinking (rough for a sunday night) increase in revs in our diesels, probably means excess fuel. so it's possible you had a slight blow-by from the crank case, or something simple like the accelerator cable being sticky or something.

I can say I honestly dont' know to be sure though, sorry mate.

[oracle1]

Run on

The engine stopped when the solenoid de activated that"s why I"m thinking excess fuel.

[Preen59]

For anyone reading this that doesn't understand.. A diesel's engine speed is controlled by the fuel. There is no actual "throttle". Basically, the engine draws in a full cylinder of air no matter the throttle position and the power it can make is controlled by how much fuel is injected into the cylinder upon charge compression..

[Greg Roles]

My guess is fuel plus the oil blowby gunk buildup was causing increased fuelling, as you mentioned it hasn't done 100kph for ages. It is odd that the fuel solenoid shut it down, but perhaps it was the fact the two combined gave enough to have the thing behaving eratically at highway speeds, and once the diesel was cut the thing slowed enough to no longer be "drawing" the gunk off the inlet walls??

A good flush wouldn't hurt, both fuel system ala Fueldoctor etc, and a de gunking of the inlet, much fun there!

[gldgti]

blowby, no doubt about it.

hey everyone,
Your symptoms are dead set straight down the line early onset blowby issues. experienced it myself many a time. re-ringing hte engine will fix your problem for a time, but for now there are a few things you can do to minimise the issues:

1. check what mannor of vent system you have. early engines have 1 pipe from rocker cover to intake manifold. later ones have a hose from crankcase (on the front of the block) up to the manifold and a tee to the rocker cover. later revision helps to minimise hte blowby effects for a little while.

2. install a catch can in the vent system. you can go rudementary (like a jar with an in and out) or fancy (pro-vent system). both will work.

3. early diesels tend to get to a ring wear stage at which the engines run well but suffer increased oil consumption and blowby. ultimately, you're looking at a re-ring at best, or maybe a hone and some new pistons.

dont be fooled by you apparrent control of the situation (being able to turn it off). in the coming months as the weather warms, the problem will get worse. driving fast also doesnt help (short gears are really the problem).

start using a nice heavy oil (20W-60 or the like) and be buy a ring set

a catch can will get you another 20-30,000km if your lucky

oh btw - change you oil now, and check out just how runny it is. it'll be full of fuel as preeny suggested. likely the level on the dipstick doesnt drop too far between changes nowadays right?

[gldgti]

My guess is fuel plus the oil blowby gunk buildup was causing increased fuelling, as you mentioned it hasn't done 100kph for ages. It is odd that the fuel solenoid shut it down, but perhaps it was the fact the two combined gave enough to have the thing behaving eratically at highway speeds, and once the diesel was cut the thing slowed enough to no longer be "drawing" the gunk off the inlet walls??

A good flush wouldn't hurt, both fuel system ala Fueldoctor etc, and a de gunking of the inlet, much fun there!

early diesels dont suffer from inlet gunking up, there's no EGR they get a nice oil slick, but its always liquid and comparatively clean - all the better for burning as fuel.