Oil light and cylinders sound

[rbryson]

After I ride the bike for 10 miles or more, stop and then re-start the oil light comes on followed by what I perceive to be pistons trying to sieze up. If I put it under load or rev it up the light goes off and the power returns. I recently changed oil and someone mentioned that it sounded like the oil filter had been improperly installed, something about an inner seal being lose. If this is so, I was wondering if I could remove the oil filter temporarly to see if the problem goes away. Can an R90/6 run without an oil filter for a short distance? Thanks for any advice.

[20774]

Did you change the filter at the same time you changed oil? Was this a problem before or after you changed the oil? I would certainly reinvestigate and look at the filter and all o-rings in that area. IIRC, the /6 should have the inner bolt that seals the filter in place. If the oil light comes at all when the engine is running, that's generally a sign of a serious loss of oil pressure. If the oil pressure sending unit is working properly, it only takes a small amount of pressure (7-10 psi?) to extinguish the light. If indeed the pressure drops that low for any extended period of time, you're doing damage to the bearings.

Kurt in S.A.

[jbcollier]

Stop riding the bike!

Double check proper oil filter installation before running it again.

[Na Cl K9]

Refer to Mat Parkhouse's article on oil filter replacement in one of the recent
ON magazines if you have that one or can borrow a copy. Do NOT run the engine without an oil filter...How long have you owned this bike by the way?

The oil light should come on when the ignition switch is turned on, extinguish when the engine starts. It should stay off until the engine is stopped or the oil pressure drops below the threshold of the sensitivity of the switch. If it is lit while the bike is at idle, there is a problem.

Sometimes with an old, worn or dirty starter motor, the engine heat will increase the resistance in the starter causing it to "drag" which can make it seem like the pistons are moving much too slow as in "trying to seize up". This situation can be compounded by a weak battery or bad (dirty) electrical connections.

You can check your oil filter installation to see if it is correct. Take the tank off and set it carefully aside. Drop the float bowls, pour the fuel back in the tank and replace them on the carbs. Lay the bike over on its side with the valve cover on a section of 2x4 wood block (with the oil filter access cover up of course). You can then remove the outer and inner cover and inspect the installation without loosing oil. For the few minutes it will take to do this you will not have to worry about brake fluid or battery acid leaking or the cylinder that is down filling with oil...don't let it sit there on its side all day..

Modern filters have soft rubber seals attached at both ends. Check to make sure they are intact. Look in the very back of the filter canister and see if there is a rubber 'O' ring still in place on the center shaft. It can be black white or red and is not at all like the soft rubber seals attached to the new filters. If you find one there, it is a left-over from times when the filters BMW sold came with two separate O rings. It needs to be removed and to do so use a piece of stiff wire with a 1/4 inch "L" shaped bend at the end to reach back into the housing behind the ring and work it off of the tube and out of the canister..

Replace the filter, inner filter cover, tighten the inner cover bolt and replace the outer cover with gasket, stand the bike up again and replace the tank.
Re-install the fuel lines but do not turn on the gas to fill the float bowls yet.
Check the oil level with the dipstick just to make sure.

Turn on the ignition and verify the oil light is lit. Turn the motor over with the starter and verify that the oil light goes out. Turn on the gas and start the engine. Verify the light goes out and stays out. I must point out that folks get confused between the generator and oil lights all the time…happened just recently on this forum. The generator light stays lit to around 800 to 1100 rpm. and then goes out.

[cjack]

Replace the filter, inner filter cover, tighten the inner cover bolt and replace the outer cover with gasket, stand the bike up again and replace the tank.
Re-install the fuel lines but do not turn on the gas to fill the float bowls yet.
Check the oil level with the dipstick just to make sure.

Turn on the ignition and verify the oil light is lit. Turn the motor over with the starter and verify that the oil light goes out. Turn on the gas and start the engine. Verify the light goes out and stays out. I must point out that folks get confused between the generator and oil lights all the time…happened just recently on this forum. The generator light stays lit to around 800 to 1100 rpm. and then goes out.

As far as oil pressure is concerned, it doesn't matter if there is an oil filter, o-rings or not. If the cover is in it's proper place and the cover bolt (#5) is snug, there will be normal oil pressure. If this is related to an oil filter change, then I would assume that the cover is loose or not seated properly.
If not, then I worry about the loss of a locating pin for the main bearing allowing it to rotate and shut off the oil flow.