Petrol in oil ?

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
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Petrol in oil ?

Postby davehutch » Thu Jul 31, 2008 3:55 pm

Got my G2 running the best I can (still spitting and spluttering). I took it up the road and back. It went better than i thought. But on checking levels the engine is now full to the top can it be petrol and what does that mean ?
----Only a biker knows why a dog sticks his head out of a car window.

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Petrol in oil ?

Postby SPRIDDLER » Thu Jul 31, 2008 7:48 pm

Dave,
I can't see any way that petrol can get in the oil.
By how much has th'oil level risen?
The level in my oil tank usually rises a bit (1/2 inch?) on the first start of the day since oil which had settled in the crankcase 'sump' after the engine stopped gets returned to the tank. Yes, at the same time oil is pumped from the tank to the engine but the rate of the return flow is always greater than that of the feed flow.
If you have a problem of 'wet sumping' there could be quite a bit of oil collected in the 'sump'. Some say a pint or so, although Marigold has never wet sumped at all.
Of course if you have topped up the oil tank after the bike has stood for a couple of days it will appear that the level becomes unnacceptably and mysteriously high when you run the engine.
You're welcome.

Oh dear It has just dawned on me that I think the G2 tank is integral with the engine isn't it, and not a separate unit as with the heavyweights?
IKBA about G2's (stating the bl*****g obvious again) but there may be some help in my wafflings.

Edited by - SPRIDDLER on 31 Jul 2008 7:52:02 PM
I poke badgers with spoons.

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Petrol in oil ?

Postby itma » Thu Jul 31, 2008 8:05 pm

As he has been playing silly buggers riding with the choke on, it is quite possible.
Also if it has been left with the taps on, and the taps are leaky it will dribble past the valve, rings and top up the sump oil, especiallly on a worn bore.
An effect exacerbated if its left on a prop stand, or as normal on a lightweight, the stand is wonky anyway
The eight stroking effect this can give as the vapours from hot oil/petrol mix get pumped back up can be amusing if its not your bike.
Smell the oil, if at all petrol-ish change it pronto
as it will wear out your engine rather quick.

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Petrol in oil ?

Postby davehutch » Thu Jul 31, 2008 8:22 pm

It's been 5-6 hours since I went up the road and the level has dropped now but not down to the right level. I drained the old oil before i went out and filled it to 1inch below the filler hole as it said in the book. Its now about half inch below.
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Petrol in oil ?

Postby Groily » Thu Jul 31, 2008 8:46 pm

Best have a look at the float needle and its seat methinks . . . if that is fuel tight a leaky tap won't matter much; if it isn't, petrol everywhere, inside and out and No Smoking in the Shed. I seem to replace these needles and valves with monotonous regularity - every time I get another bike that hasn't run for a bit in fact.
And if the oil is thin and smells a bit too refined, yes, change it quick!

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Petrol in oil ?

Postby SPRIDDLER » Thu Jul 31, 2008 8:51 pm

quote:

Also if it has been left with the taps on, and the taps are leaky it will dribble past the valve, rings and top up the sump oil, especiallly on a worn bore.



You're right Ken, but I had assumed that if there was so much petrol leaking around Dave wouldn't need to ask the question of whether it could be petrol - he'd be hallucinating in the shed.
I must write out a hundred times "Do not assume", it makes an ASS out of U and ME. Err, me as it happens.
Ugh, Consultant-speak. Thought I'd left all that behind. It's odd how(this) one remembers the most creepy things!

Edited by - SPRIDDLER on 31 Jul 2008 8:55:58 PM
I poke badgers with spoons.

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Petrol in oil ?

Postby davehutch » Thu Jul 31, 2008 9:22 pm

Thanks lads, I think I have carb problems any way. Getting the carb sorted is the next thing.
Going to talk to the lads at my local section next week.
----Only a biker knows why a dog sticks his head out of a car window.

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Petrol in oil ?

Postby SPRIDDLER » Thu Jul 31, 2008 9:47 pm

quote:

Thanks lads, I think I have carb problems any way. Getting the carb sorted is the next thing.
Going to talk to the lads at my local section next week.



Better stay inside - away from the smokers
I poke badgers with spoons.

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