150 optimax diesel!

[Falcon]

A marine petrol supply has been contaminated with white diesel. Unknowingly I have burnt 150 ltr of it with no direct problems since then i have burnt another 300 ltr of clean petrol with no problems. The engine now has poor running and serious miss firing, i have changed the fuel filters and the plugs the leads are in good condition. Would anybody be able to offer any advise as to the next step and the long term effects of diesel in petrol and diesels behavior in petrol, does it separate from petrol and float or drop to the bottom of the tank?

[TIM]

Petrol and Diesel Mix up no problem......

How much diesel was in the petrol, I am asuming very little, because it ran OK with the diesel in it, and no smoke or missfire.....

Is the engine firing on all cylinders??? you can check this by pulling of one lead at a time , while the engine is running? If you do find a dead cylinder, do a quick comprssion test to make sure everything is OK........

The Only thing I could think that happened, is that, diesel burns much hotter than petrol, and you have damaged a piston.... but its unlikey....

I wonder would diesel effect the fuel injection nozzle??????

you could have am unrelated problem too>


PS I hope I havent added to your worry!!!!

[Scary Des]

Originally Posted by TIM

................you can check this by pulling of one lead at a time , while the engine is running? If you do find a dead cylinder, ...................

Be careful pulling leads off, these things are high voltage and can hurt.
Des

[tue]

DO NOT PULL THE LEADS OFF AN OPTIMAX WHEN ITS RUNNING!! You WILL get a big shock even with the proper pliers. There is a proper test to perform with the DDT to check sparks. Also you can check the injectors are all firing etc. Chances are the injectors have become blocked.

[Falcon]

Thanks for your advise i will not be touching anything while the engine is running. I am awaiting the engineer to test the boat when under load as it ticks over okay. Does anybody know how easy the injectors are to get hold of and to change. I had a new gears and casing recently and it took 5 days to get the parts. I run the boat commercially and at the moment it is the height of the season. Has anybody else experianced problems with Mariner parts.

[gavin]

Have you considered running some difiteene in with the petrol to clean the system

[Falcon]

I have never heard of difiteene is it readily availiable and commonly used?

[Rogue Wave]

The injectors are standard Bosch jobbies as fitted to BMW and Vauxhall so they could be tested at a Bosch injector place near you. Th Opti has two injectors the fuel injector is on the outside of the rail and the air injector is on the inside (which you won't be needing to touch!)