Generator light and pinging sound

[rbryson]

When I restart after the engine (1975 R90/6) is warm the oil light comes on followed by a pinging noise within the engine. Once I rev up or put a load on the engine it goes away but sometimes takes 30 seconds before the light goes out and pinging abates. The engine feels like it is stressed during this time. Accurate diagnosis appreciated.

[PGlaves]

What is the RPM when the light is on and the pinging is occuring. The alternator and ignition are not interconnected.

What I THINK is happening is that the advance mechanism is messed up and on restart the timing is off - the engine is stumbling so the RPM is low - thus the light comes on.

An alternative cause would be a very lean mixture causing both the pinging and the stumble and low RPM. I've only seen this with boiling fuel which was on a K bike - but .....

[20774]

Just to be sure, you're not confusing the oil light with the generator light??

Kurt in S.A.

[rbryson]

I am new to this Forum and tried to edit my mistake as soon as I caught it. Yes, it is the yellow oil light that comes on, not the red generator light, when the engine is hot and I re-start it. The is also a pinging sound, almost as if the engine is being denied oil. The crankcase is full of oil however. Is this the oil pump going bad? Do they even have oil pumps? Please advise.

[PGlaves]

Ignore my earlier post.

Don't run the engine - that is a death rattle.

Did you recently change the oil filter. It sounds like low oil pressure which often happens when the oil filter install isn't done right.

I think (from memory) that yours has the inner cap and the outer plate. It sounds like the inner cap is loose. Oil pressure drops but the oil goes back into the pan without an outside leak. Check this first - and don't run the engine.