contaminated fuel

[TomLS]

Just a quickie.
I've been offered 25l of petrol with 1-2l of diesel in it. I'm almost certain it'll be fine in my moggy, I've run it in my v8 before with no adverse effects, but just on the off chance I thought i'd make sure it will be ok!

Cheers,
Tom.

[robberred1993]

I assume that if you put like 10 litres in then filled your tank it would be fine, then do it again and that should make it weaker......I'm guessing the weaker you make it the better it will run.

[bmcecosse]

It will be fine - slightly smoky - but will 'clean out' the combustion chambers nicely!

[TomLS]

Cheers guys. I had roughly half a tank which I topped off with the contaminated fuel, and I've made it home with no adverse effects at all. Good to know it will have the bonus cleaning effect too!

[rayofleamington]

personally i'd avoid it like the plague in a petrol engine - even a lawn mower.

However diluted a galon per tank full into a diesel eviacle (even a modern diesel) it will do no harm at all.

[TomLS]

Why do you say this Ron? I've heard (and seen the results) that even a small amount of petrol in a diesel is the fastest way to a dead injector pump and lots of swarf in the bores, but tht was possibly a higher concentration.

I have, however, discovered a couple of issues with the diluted derv mix I'm running. Under heavy acceleration the engine has started pinging due to the lower octane, and the engine 'runs on' when up to temperature.
Tonight I drain the tank, refill with petrol, and add some octane booster.

Guess the a series is more sensitive than the RV8

[rayofleamington]

Why do you say this Ron? I've heard (and seen the results) that even a small amount of petrol in a diesel is the fastest way to a dead injector pump and lots of swarf in the bores, but tht was possibly a higher concentration.

Diesel in a petrol engine can lead to serious damage - the pinking and running on is a sign of problems.
For this reason, the diesel fuel pump nozzle is larger than a petrol filler hole!

Fuelling the other way round (very small amount of petrol in a diesel) - especially with a small concentration is not a major issue. It would need to be a higher concentration to damage the injector pump. With a higher concentration the lubricity value (oilyness) wouldn't be enough for the pump. Some pumps are more succectible than others to damage from low lubricity, but 2 or 3% petrol is probably within the limits of fresh diesel!

[bmcecosse]

Just burn the fuel off on a run - don't go draining out perfectly good fuel! If pinking badly - drop the timing back very slightly. It won't do any permanent harm - as long as you don't let it pink of course.

[TomLS]

After the joy I had, it's staying in there!
Tried siphoning it out with a hose, but after some burning lungs and a banging headache I gave up on that. Spent 2 hours looking for somewhere in the city that sold a fuel siphon, but they had all sold out! The pikeys must be gearing up...
Any way I considered attacking the timing, but going for the easy option I richened the mixture by one flat, and now you have to try very hard to get her to pink.
However, lesson learned - next time I'll stick to paying for my Moggy's fuel, and stick the dodgy stuff in the V8...