Petrol Mixing in With Oil, is it possible?????

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Dec 27, 2005
I have just had my bike running and have had exxexive oil spitting out the oil tank breather and narrowed it down to the tank being to full, while i was checking the level i discovered the oil was very thin, this got me and my dad thinking about what the problem could be making the oil thin and also raising the oil level and he suggested it may have been due to petrol from exsessive kicking and not getting it running going into the bore then running down into the sump is this possible.

Regards Julian Stap
It is possible to flood the engine with petrol, but the amount of extra fluid that you indicate was in the oil tank seems more to be more than would be drawn in with normal kicking. One possibility is that one or both carb float valves are sticking open allowing petrol to run into the inlet manifold, although this will normally manifest itself in a very obvious overflow from the carb tickler breather. How much kicking did you have to do to get it fired up? and once running was it running properly.
On another point did you innitially check the oil level while the bike was running? Most experienced Norton owners never fill the tank up to the maximum on the dipstick as this is actually too high and leads to leaks from all sorts of places, the general practice is to run the level between minimum and maximum on the dipstick while the engine is running.
My inclination would be to make sure that the bike starts and runs reliably (starting within about 5 kicks even when cold), not running too rich etc. Then drain the oil tank, sump plug and filter if fitted. refill with fresh oil, set the level while running at normal operating temperature then moniter the level after every ride.

Good luck
The right cylinder will fire after about 3-10 kicks in the cold and after about runnning on 1cylinder for about 3 minutes the left hand side will kick in. I was kicking for about 10minutes before i gave up and then later that day tried for around 5 when i got it ruinning and first noticed the oil blowing out of the breather hose, the carbies dont seem to be flooding due do when i tickle them it doesnt just pour out the little hole. I am going to put in an electronic ignition and power box and a few other electrics and hopefully this will fix the starting problem, once the bike is warm it starts 1st kick and will also do in summer. I have drained the oil and will take your advice on where i fill it to.

Edit: Just so you know the carbies have no choke and i am running velocity stacks and it is cold as this would lead to the large amounts of kicking.
I am puzzled as to why it only runs on one cylinder and then two after a few minutes. It sounds like the left cylinder may be running too rich and flooding until there is enough heat in the engine to dry the plug out. After kicking it a few times when cold why not pull the left plug out and check whether it is wet or not. It might be wet due to a weak spark (check points gap, condenser, coil etc.) or due to over fueling on that side, possibly high float height (try swapping float bowls, bowl gasket, floats and valves from the right carb to the left and see if the problem switches over). I am running electronic ignition on my bikes and can recommend it although the bike should also run perfectly well with points.
ok will try that out tomorrow as it is 10:30 in Aus, i only tickle the left carb because i need to fix the tickler on the right could this contribute to my problem of flooding in that side, also as stated above i am going to get elctronic ign and a few other electrics to bring it into the 21st centuary
Jullian, It is a good idea to start from the premise that every setting and adjustment is as it should be, before looking for other faults, so for example the fact that your right side tickler is known to be not working is the first thing that should be tackled, especially since you have already stated that your carbs have no choke mechanism. If you have no chokes and no tickler on one carb I am not surprised that your bike is hard to start. Is there a reason for the lack of chokes? I also have velocity stacks on my bike but still retain the chokes and it starts 1st or 2nd kick hot or cold. If you have clip-on bars you can either mount the choke lever on a short piece of handlebar mounted in the original top clamp, or else order a 1 inch diameter choke lever for vintage Triumph bars and mount it on the down tube next to the oil tank (I have done this on my bike). The tickler mechanisms (new type) are readily available and not very pricey, Pt number 376/086A I can recommend 'British Spares' just down the road from you in NZ. You will need to remove the carbs and I had good results using a small vice to press the new parts in. If you want to check that one of your problems is lack of fuel in the right carb since you probably have no air filters why not squirt a little fuel down each intake with a plastic squirt-bottle and see if this fires it up quicker.
As a general rule regular excessive flooding of cylinders can lead to premature wear, as the petrol washes away the lubricating oil from the cylinder walls so you do need to solve this problem ASAP. [/b]
Dave, like Julian i'm also from OZ, but on the opposite coast, i have no chokes on my bike either and don't need them, the conditions in the sub tropics here lend themselves to easier starting, even in winter, i don't know what it's like where Julian is.
well im 4 hours from melb in the malle so generally the weather is cold in the morning and hot in the arvo, no reason not to have chokes it has never had them since my dad last had it running around 25years ago i will definatly fix the tickler and will look into getting my amals resleeved can anyone direct me to where i can get the sleeves from so i can get my local machinest to put them in.

thanks for everyones help.
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