Runaway diesel, black fuel in return line

woodster · Jul 24, 2013

zeehag said:
perkins do not have pressure release levers that i know of--i know my yanmar in my ericson has one. it cracks all injectors, both of em, simultaneously...lol funny thing about that......

actually the yanmar compression release levers hold open the exhaust valves to let the compression out of the cylenders....

hope the damage is not to intense.....

regards

woody

Jake N Eggs · Jul 24, 2013

Z, Anchor is correct in what he is saying, assuming that the understanding of what your mechanic did to stop the runaway is correct. If your mechanic loosened the fuel injection lines going to the injectors he released the fuel pressure and without the fuel pressure the injectors will not fire. If this is the case he only turned off the fuel supply to the engine and the problem is most likely in the governer of the fuel pump. In order to release the compression of the engine the injectors would have to be removed.

Considering that you have black fuel in the system I think that having the fuel pump rebuilt is a prudent move. This is of course, if your mechanic actually released the fuel pressure to shut the engine down.

I wish you good luck with this repair and hope you get under way quickly and without too big a hit to the pocket book.

jviss · Jul 24, 2013

zeehag said:
perkins do not have pressure release levers that i know of--i know my yanmar in my ericson has one. it cracks all injectors, both of em, simultaneously...lol funny thing about that......

That doesn't make any friggin sense to me. I've read this entire thread and I still can't tell what you mean when you say "cracked the injectors." Do you mean that the infectors were loosened where they screw into the cylinder head, or do you mean the fuel lines at the top of the injectors were loosened?

I guess it could be that a compression release "cracks all injectors," but it sounds like the misapplication of a term to me. If you think that "crack the injectors" is a general term for relieving the pressure on a cylinder, then you are mistaken.

I can vouch for anchorklanker based on my experience with but a single engine, a Universal M25/Kubota D850, it would be difficult indeed, if not impossible, to loosen the injectors in the head without loosening the fuel lines firs; and it would be downright dangerous, and foolish to attempt to relieve cylinder pressure this way, you could end up with and injector through your head.

I suspect you only know what your mechanic did based on what he told you, and there's some kind of communication problem. I suspect further that it was cracking the fuel lines, "the nipples," so to speak, that stopped the engine, that it was a failed governor or injection pump that caused it to run away, and not that it was running on its lube oil blowing past the rings. It might have been burning some lube oil, and returning some dirty, black lube oil to the fuel tank due to an injection pump seal failure.

jviss · Jul 24, 2013

Sensational home page title for this.

I'd like to call B.S. on the title for this on the home page. It says "Zeehag's diesel ran away and blew up, ...." It did not blow up! This is clearly stated in the original post.

Jake N Eggs · Jul 24, 2013

jviss said:
I'd like to call B.S. on the title for this on the home page. It says "Zeehag's diesel ran away and blew up, ...." It did not blow up! This is clearly stated in the original post.

jviss, here is the title: Runaway diesel, black fuel in return line.

jviss · Jul 24, 2013

Jake N Eggs said:
jviss, here is the title: Runaway diesel, black fuel in return line.

I was referring to the title, or headline on the catalinaowners.com home page.