Ducati Sporting Club UK > General > Idle Chat > Techie type question

[Nigel C]

Is the specific gravity of diesel greater then unleaded petrol??

[Carbon749]

have you put the wrong fuel in the car / bike ?

[Nigel C]

Ermm i'm not admitting to anything yet

[rockhopper]

Diesel is 820 to 950 kg/m3.
Petrol is 737.22 kg/m3

[Carbon749]

If you are not in a hurry for the answer I will be able to give you the exact figures when I am back at work in the morning. (Update - Rock Hopper has beat me to it as I was typing this)

I work in the lubes division of a major Oil company and I'm sure one of my colleagues in fuels will be able to advise the SG of the fuels.

If you do have a problem, you can U2U me and I'll see what I can do to help.

[Edited on 17-4-2006 by Carbon749]

[psychlist]

Originally posted by rockhopper
Diesel is 820 to 950 kg/m3.
Petrol is 737.22 kg/m3

That'll be a yes then
Nige, they mix too well for you to seperate them from your tank mate, Drain it all off and replace the fuel filter, take your plugs out and give them a good clean. Give the dieso to anyone with a diesel motor and refill with petrol, turn the engine over in a nice BIG open space and wait for it to fire up, then make sure you're wearing a smoke mask! It won't have damaged anything as dieso is a light lubricant. Not that I'm speaking from experience of course

[Carbon749]

Originally posted by psychlist

That'll be a yes then
Nige, they mix too well for you to seperate them from your tank mate, Drain it all off and replace the fuel filter, take your plugs out and give them a good clean. Give the dieso to anyone with a diesel motor and refill with petrol, turn the engine over in a nice BIG open space and wait for it to fire up, then make sure you're wearing a smoke mask! It won't have damaged anything as dieso is a light lubricant. Not that I'm speaking from experience of course

That is unless you put unleaded in your diesel and tried to start it ... not good.

I did it the other way around ... put about 5 gallon of diesel in to my petrol car. Thankfully the tank was almost empty so I filled it to the top with unleaded and just let it smoke for a while

[guest1]

Would it be advisable to turn it over with the plugs out first and a couple of rags over the holes? (After refilling with petrol of course)

[Nigel C]

Thanks for the answers i asked because on looking in the tank and having a sniff couldn't smell diesel .
I filled up at the station on the roundabout north of boxhill, i definitely filled up with unleaded albeit from the pump with a diesel nozzle.
(green premium unlead sticker on nozzle and on the place where it sits, diesel nozzle is black ) .
Tank was about a third full when i refilled , got about 5mls onto A29 when it started to hesitate on acceleration, i thought it may be carb icing so stopped to let the carbs warm up while doing this i was blipping the throttle and noticed bluey white smoke when i shut off .
Started off again and thought no more of it as it cleared up at the top end of the revs , by the time i got near home it was not accelerating properly and backfiring on part throttle, then it went onto 3 cylinders with clouds of bluey smoke on the overrun.
Got home but it wouldn't start next day i'm not convinced it's diesel because surely i wouldn't have got 40 odd miles from boxhill
And also if it was burning diesel surely there would have been smoke under acceleration there was none why only on the overrun did it smoke ?? i was using the top end of the rev range because that was the only way to get any decent acceleration.

[psychlist]

It doesn't sound like diesel contamination Nige, I know you know I know what i'm talking about mate
Get Alf to have a gander