Petrol in a diesel engine

The other thread about someone using the wrong oil prompted the following:

Does anyone know what exactly happens if you fill a diesel tank with petrol? Someone once filled a petrol tractor from the diesel tank and it was not happy (just drain and replace). But I am curious about how petrol performs in a diesel engine. I doubt that the result would be spectacular. Diesel has a higher energy density than petrol so petrol is unlikely to blow the thing up. So I would expect that petrol would work. As with oil, I suspect that the net result would be nuisance rather than disaster.

But has anyone tried/experienced it?

Reply to
Ken
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This has been done to death on uk.rec.cars.maintenance. The consensus is that modern common rail cars can't go very far like that as it knackers the injector pump (which relies on the lubrication of the diesel). An older simple diesel like a 405 or earlier Xants should be relatively ok so long as you don't go too far, they do get very rattly and bangy though or so I've been told.

Reply to
malc

You used to be able to add quite a lot of petrol to your tank of diesel in days of yore to prevent waxing during winter. Apparently 25% petrol was allowed in old Golf diesels, and a bloke in PPC running a 205D on veg oil adds a bit of petrol to a tankful to thin it down a tad. In something like a ZX or similar that's nice and simple, you should be fine.

Common rail and you'll kill the pumps...

Reply to
Doki

The consensus seems to be that if you put petrol in a diesel tank by mistake, if the proportion of petrol is low when you discover the error, probably filling up with diesel immediately will be sufficient. If the proportion of petrol is high (>50%?) maybe drain the fuel tank and replace. As I said, the reverse is not the case. Someone (everyone denied having done it) put diesel in a petrol tractor here and it was unhappy - it would stop often and restart with difficulty. Drain and change was the only option.

Waxing of diesel was a problem in Australia about 20 years ago - the refineries changed their settings (and denied having done so) and whole fleets of tractors were unstartable in winter until you blasted them with heat. The outcry/outrage of users was sufficient to prevent it happening again (up to now anyway).

Reply to
Ken

I really wouldn't chance any proportion of petrol in a common rail car. For the sake of losing the cost of a tank of fuel VS the cost of swapping the pumps, it'd be the tank of fuel that's swapped every time for me.

Reply to
Doki

Hi,

Eeeer, pumps, injectors... Mostly all of the fuel line indeed, if the engine doesn't burn in the meanwhile ! A friend of mine (OK, a friend of mine's wife) filled up her 406 HDI with petrol. She saw it immediately and called the hauler, she just had to cope with a tank flush, seems to run fine anyway.

I've heard of a guy which did the same with a Safrane 2.5TD (crappy engine anyway) and didn't realize - I won't explain the details of the story - and despite being an old-class Diesel, had to change fuel line and the complete engine.

Regards,

-- G.T

Reply to
G.T

They must have been tougher in the 60's. A colleague tried to save me some hassle and filled up the Morris LD diesel Royal Mail van that I was to drive that afternoon. Unfortunately, the petrol and diesel pumps being side by side, he filled it with petrol.

I arrived and went on my trip and for the first 5 or 6 miles it ran fine but then started to kangaroo a bit. Fortunately my journey took me past the workshops so I pulled in and, after examining it, they told me it wasn't a f###ing two stroke.

They drained the tank, refilled with diesel, bled it and sent me on my way. It ran fine for some years after that.

The pumps in the yard were hand operated and shortly after that, the same colleague put the petrol hose in a van and proceeded to turn the handle on the diesel pump. Unfortunately he was standing directly below the nozzle. Ruined his suit and his car stunk for weeks because he'd driven home in it to change.

Reply to
Keith W

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