so this is when oil seeps thru the oil pump and accumulates in the crankcase?it happens when a bike sits for a while?I understand it can ruin an engine,I need educated lol. my bike smokes a little after starting although it does have new pistons and rings..i chalked it up to seating of the rings but now I dont see the oil coming out the pipe in the oil tank..help.
Morning Fenderman,
Wet sumping is as you describe. It can be be very slow and barely noticeable or it can be extreme and happen over night with just about all the oil ending up in the sump. I have never known this to ruin an engine but I suppose if you managed to start the engine with all the oil in the sump it would be possible especially if you it could actually rev it up.
A bit of smoke on a new bore is acceptable but it should decrease as the rings bed in.
Oil not returning to the tank is more of a problem as it indicates that the pump is not working. Assuming that there is oil in the tank and therefore in the sump, the pump should pick it up and return it. Even a very worn pump will return something. I would suggest not running the engine as if the pump or the pump drive has failed then little or no oil will be going through the timing side bush to the big ends. Take the sump plate off and check that the pick up pipe is not blocked and that the ball is not stuck.
If this all looks good then I would take the timing cover off to check that the pump is still secure and that the drive worm is turning it
A very worn drive worm can be just working and then with bit more wear fail to turn the pump. If the drive pump drive looks good then it will probably be necessary to remove and strip the pump.
So start with the simple things and check the pickup pipe and ball in the sump and take it from there.
Dave.
I did confirm that the ball is not stuck on the pick up tube.isnt there supposed to be a certain amout of oil laying in there? when I dropped the plate/screen there really wasnt any oil that that drained out. how does the pump pick up the oil if there not a certain level all at start up? I did take out the oil pressure regulating valve body and made sure the ball and seat were clean too..I also took of the line from the tank down to the crankcase and blow out to confirm free flow of oil from the tank to engine..gonna take of the side cover and look at the pump drive tomorrow..
Did you ensure there was no airlock in the feed line after you refilled the oil tank?
Good morning,
The return side of the pump can only return oil that has accumulated in the sump. This oil gets there after it has been pumped by the feed side through the crank and then drains down. There could be a bit from wet sumping and once an engine has been running the oil that has been flung about in the crankcase will drain down leaving some oil in the sump.
When a pump is working at its best it will suck all of the oil out of the sump. This can be seen as the return to the tank can get quite spitty. I think the scavenge/return capacity of the pump is twice that of the feed/pressure side.
You could put some oil in to the sump to check the return of the pump but if there is a problem with the pump itself then starting the bike to check this could cause damage.
I think you are doing the right thing by checking the pump and pump drive as only a bit of time and perhaps a gasket is lost rather than a bottom end.
Dave.
Quote from: fenderman! on 14 Jul, 2020, 23:11
I did confirm that the ball is not stuck on the pick up tube.isnt there supposed to be a certain amout of oil laying in there? when I dropped the plate/screen there really wasnt any oil that that drained out. how does the pump pick up the oil if there not a certain level all at start up? I did take out the oil pressure regulating valve body and made sure the ball and seat were clean too..I also took of the line from the tank down to the crankcase and blow out to confirm free flow of oil from the tank to engine..gonna take of the side cover and look at the pump drive tomorrow..
Unfortunately, this type of problem can be a real pain to sort out. If you have checked all the obvious things that you can readily get your hands on then you might end up having to take the pump off so that you can check all the oil ways and the non-return valve behind it.
Did you prime the pump on rebuild? Are you sure the pipes are on the right outlets?
How do you prime it?never took the pump off to rebuild motor.
Prime the sump by putting oil into it via rocker cover, 1/2 pint was recommended for the A65.
The return side of the pump should start to return it to the tank after repeatedly kicking the bike over with plugs out and magneto earthed.
However if you found no oil in the sump after running the bike sounds like the feed side of the pump is not working. As said by Oldbiker could be an airlock in the feedside. Release the feed pipe at the crankcase union and allow oil to flow out. You can try pumping into the union with a pressure oil can. When all done up again slacked the pressure relief valve and kick over repeatedly as above and oil should eventually be pumped out.
Just make sure that the oil pipes are correct ie inlet and return, I have seen chaps rebuild & stick them on the wrong way round.
The lines are correct I believe.i was getting flow out the pipe in the tank before.so if I take off the pressure relief valve and kick the motor,I should see oil squirting out right?
So julian,your saying if I remove the pressure relief valve and kick over the bike,oil should be squirting out?
You should get a flow of oil, probably not squirting out. It will take a few kicks to get it moving. If not you need to investigate the pump.