Engine Shut-Off Problem '03 Volvo

[Weyalan]

We have a problem with shutting off our engine:

It is a Volvo 2003 (fresh water cooled). It has individual injector pumps for each cylinder

The problem has only developed over the last 2 or 3 weeks, before which we had had no problems at all with the engine.

The problem is that it has become increasingly difficult to stop the engine.

In theory, we just pull the engine-stop cable fully out, and it stops... as it has done for the last 3 years. But over the last couple of weeks we have been having to pull the cable out lowly to try to find the "sweet spot" where it will stop because if we pull it out fully it begins to stop (i.e the revs drop) but then goes back to idle revs (about 800rpm).

The problem has become so bad that I sometimes have to control the engine-stop from the engine and use the decompression lever to stop the engine.

I'm guessing that the problem is with the governor. Any advice is gratefully recieved. Thank you.

Patrick

[Weyalan]

Nobody have an opinion / advice or come across a similar problem?

[Chief Engineer]

Sounds like a problem with the cable.

Disconnect it at the engine

Start the engine then see if you can stop it at the engine.

Don't start taking the governor apart.

[CaptG]

Had the same problem with a 4-108. It was all about the cable. It wasn't moving the shut off lever far enough to completely kill the motor. It had slip in the mounting. Secured it properly and all is well. Hope this helps.

[Tropic Cat]

I'm interpreting your post to mean you can stop the engine by moving the engine stop lever at the engine. If this is the case, it's the cable. They do go bad in time. If not... how's your engine oil level? Down a bit?

[Weyalan]

No, the problem is definitely not the cable. The cable is fine. It doesn't matter whether I use the cable or actually manually rotate the stop lever on the side of the engine, we have the same problem.

It is very difficult to stop the engine. I have to find the "sweet spot" in the travel of the sop cable (or turning the lever on the side of the engine) to try to stop it, and even then, most times I have to pullup the compression lever to get the engine to stop.

[Tropic Cat]

Oil Level?

I'm asking because if the piston rings leak on the compression stroke, the crank case oil mist gets blown through the CCV (crank case vent) and into the intake. This can feed unregulated fuel into the combustion chamber. If you add a restricted or dirty air filter voila, the engine keeps running.

At least that's one cause.

Another would be a worn stop valve as it mechanically operates off of a cam.

[Weyalan]

I'm pretty sure oil level is fine, but will check that tonight. I will also check the air filter (but on this model, the air filter is just a wairly open weave wire mesh, so is unlikely to be a problem). I'm guessing its a worn stop valve, but I am very wary of opening up the governor in case it explodes into a million tiny cogs, bearings and springs... never to be re-constructed.

[speedoo]

I'm very curious Weyalan... were you able to diagnose the problem?

[Chief Engineer]

Sounds like the cable has stretched.....is there a lever on the engine the cable goes into?

Is there a "stop adjustment" to set the travel of the stop lever?