I've been digging into the 'new' 1978 R100/7 which I bought late last year. The seller said that he had changed the oil and oil filter fairly recently. When he started the engine for me oil started to leak out of the oil filter cover. He snugged the cover bolts a bit more and it seemed to stop, so I took it for a short test ride of 3-4 miles. After I trailered the bike home, I started it up and rode around our driveway for a bit, and noticed much more oil coming out. I parked it and didn't run it after that. The oil light didn't come on while running - and I think that it still works, so maybe engine is still OK.
Fast forward to now... I've discovered the problem(s), or rather, the causes of the problem:
1. Canister Depth is very shallow - I checked it in (3) different locations and averaged the measurements and come up with 2.7mm
2. The PO installed a long style filter and didn't use a metal shim. The 1978-bikes have a sharp edged canister and the O ring was shredded in several places.
3. The inside tube of the oil filter was crushed flat.
I've checked the check valve at the base of the cannister and it is working, or at least operates when pressed with a long screwdriver tip. I've got a new hinged oil filter kit (no oil cooler), so:
1. Based on the shallow depth, I'm going to need to use, I believe, (2) paper cover gaskets - using just one seems to try to overly compress the white o ring with the metal shim in place. I get the cover screws cranked down fairly tight and the cover still doesn't seem to be squeezing the cover gasket - I can wiggle/move the gasket with my fingernail still.
2. If I double up and use (2) paper gaskets, I think that the cover and paper gaskets are pretty well snugged down with similar torque applied to the cover bolts. Based on the calculations:
2.7mm (cannister depth) - 0.3mm shim thickness + 0.45mm gasket thickness + 0.45mm gasket thickness = 3.3mm depth
The 4mm wide o ring is then compressed about 18%. I think this is OK. If I go with just 1 shim though it will be compressed almost 30%, but I don't know if the cover will be tight enough to the gasket and case to avoid leaks.
3. I am hoping that the oil filter inside being crushed doesn't imply that the oil filter flow through the inside of the filter was non existent due to pressurized canister and leaking/torn o-ring condition. Ugh.
This 1978 bike seems to have alot of 'oddities' with it. I read that Anton Largiader also measured very similar shallow cannister depths on another 1978 R100. I am thinking that 1978 was not a good quality control year at BMW...
Fast forward to now... I've discovered the problem(s), or rather, the causes of the problem:
1. Canister Depth is very shallow - I checked it in (3) different locations and averaged the measurements and come up with 2.7mm
2. The PO installed a long style filter and didn't use a metal shim. The 1978-bikes have a sharp edged canister and the O ring was shredded in several places.
3. The inside tube of the oil filter was crushed flat.
I've checked the check valve at the base of the cannister and it is working, or at least operates when pressed with a long screwdriver tip. I've got a new hinged oil filter kit (no oil cooler), so:
1. Based on the shallow depth, I'm going to need to use, I believe, (2) paper cover gaskets - using just one seems to try to overly compress the white o ring with the metal shim in place. I get the cover screws cranked down fairly tight and the cover still doesn't seem to be squeezing the cover gasket - I can wiggle/move the gasket with my fingernail still.
2. If I double up and use (2) paper gaskets, I think that the cover and paper gaskets are pretty well snugged down with similar torque applied to the cover bolts. Based on the calculations:
2.7mm (cannister depth) - 0.3mm shim thickness + 0.45mm gasket thickness + 0.45mm gasket thickness = 3.3mm depth
The 4mm wide o ring is then compressed about 18%. I think this is OK. If I go with just 1 shim though it will be compressed almost 30%, but I don't know if the cover will be tight enough to the gasket and case to avoid leaks.
3. I am hoping that the oil filter inside being crushed doesn't imply that the oil filter flow through the inside of the filter was non existent due to pressurized canister and leaking/torn o-ring condition. Ugh.
This 1978 bike seems to have alot of 'oddities' with it. I read that Anton Largiader also measured very similar shallow cannister depths on another 1978 R100. I am thinking that 1978 was not a good quality control year at BMW...