Please can I enquire about my 500 Pantah, before the bad weather set in I picked up a high pitched whine when in gear and engine pulling fairly hard. The issue I found was that the oil level was above the viewing window and clearly contained fuel. There was sharp slithers of metal on the drain plug and evidently the engine will need stripping as a bearing has picked up, the issue is why is the fuel entering the sump. The tank fuel cocks don’t leak 110% sure of that and even if the float valves where poor would this allow so much fuel to enter the inlet tracts as to drain into the sump enough to sufficiently dilute the oil and lead to bearing failure over less the say 200 mile? I’m committed to the engine strip but need to understand the underlying problems which lead to the failure. Any body experienced this any insights gratefully welcomed I beginning to think my bikes cursed Nick.
Bad weather set in? I'm still waiting for it to get better here The only possible way for the fuel to get into the engine is past the fuel taps, so they must leak although maybe very slowly. I recently saw a Hinckley Bonneville that had a gallon and a half of petrol / oil mix drained from the crankcases. This was a bike that did hardly any miles and spent most of its life in the garage getting polished. The owner wondered why he couldn't get it started. It's just as well that it didn't as there was far more fuel than oil in it. Sorry that you are going to have to do a rebuild but it will probably be a better bike after it.
Cheers for the response I am going to get the carbs overhauled as the float chamber seals seem likely. Additionally the outer clutch basket bearing is shot, if this is the only bearing that’s gone I am considering a really good flush and seeing how I go. I have the tank off and a good half full so will monitor for a leaks past the cocks, I suspect the float emptying past the needle on the horizontal cylinder and am trying not to split the cases unless absolutely required. On that subject the tool to lock the clutch is proving elusive but Luigi Moto in Bristol suggest a impact gun with the plugs in which was what I was going to do as soon as I get back from work. Nick
A new pair of these wouldn't do any harm, especially if the old ones are 40 years old: https://www.dellorto.co.uk/shop/del...rburettor-parts/phm-parts/12202-needle-valve/
Thanks going to get the carbs sorted and having a lock tool fabricated from inner and outer clutch plates so the clutch basket can be removed Bearing and tab available at MDINA so with a good flush I will see if this issue is resolved I will see what damage is behind the clutch as soon as the tool is available, nervous about breaking the outer basket or locking the gearbox and leaning on the bar to much Nick.
as said, can't think of another route for fuel to enter crankcase other than inlet/carbs. I'm sure you'll find the reason with perseverance. You probably know already a puntured float will produce the same result for example.
Had the same thing happened on my rc30, hydraulic lock. Thank god no damage caused....ended up a float in a carb bowl didnt shut off the flow and the fuel leaked past the rings.i think there are only two rings on the rc 30 hence the tenancy to use oil .
