Engine breaking up, oiled points?

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May 12, 2008
Finally got my 75 Mk3 back together and took her for a short run... short because the engine started breaking up. Nursed her home, opened the points cover and there was a puddle of oil in the bottom. So my thoughts are that the oil is fouling the points and causing the engine to sputter and miss. Does this sound correct? When I reinstalled the timing side cover I used the little oil ring seating tool and a new oil seal, but I must have messed something up. When installing the oil seal in the timing cover, does the open side of the seal (where the little metal spring/ring sits) face the engine or the auto advance? Are there any other tips or tricks I need to know about reinstalling the timing side cover? Thanks for any advice... I feel really close to being able to make her run...
Oil seal has the spring facing towards the engine.

You say that you used
the little oil ring seating tool and a new oil seal
. Are you reffering to the tool to fit the oil seal in the timing case here, or the oil seal guide tool?

If you don't use a points oil seal guide when re-fitting the timing cover, you are in danger of damaging the oil seal.

A leak from the timing case inspection cap (on a MK3) can mimick (after a run) a leaking points oil seal. Don't ask me how I know, or if I changed the points oil seal eroneously. My inspection cap wasn't on tight, and leaked very convincingly :oops:
I meant the guide tool (looks like a cone that threads into the shaft). The oil puddle is inside the points housing on the timing case, so I am thinking that the seal is either not seated properly or damaged in some way. However, I was pretty careful reinstalling the timing side cover, so I don't know what I did wrong. I suppose it could be bad parts... I purchased 2 of the plungers for the oil pump check valve and only one proved to be round, the other was a mess. So maybe I'll order a few more oil seals and try my luck again. Thanks for the advice.
Just make sure that the shoulder on the oil seal guide tool is greater in diameter than the camshaft shank, and that this is so all the way round, so that the seal drops "onto" the camshaft shank, and is not pushed across the sharp edge.

Another thing you could check is, make sure that the holes that the pillar screws that locate the points housing plate are blind, and have not been pushed , drilled or tapped through into the crankcase. This is another possible cause of the leak..
Try gently pushing a 006" feeler guage between the seal and cam all the way round and bit by bit. That will help seat the seal lip if it has been turned inside out but won't be any use if it's seriously damaged. Sometimes the installation tool does not work as well as it should.
Would the damage to the seal that is bad enough to cause oil to leak past be easy to spot? I hope to work on the bike this weekend, and I ordered a new seal, so I'll compare them. It sounds like the normal problem here is the seal lip not seating properly. I checked the guide tool and it is slightly larger in diameter than the camshaft, so hopefully reassembly this time out will fix the problem. Thanks again for the advice. Now if I can just figure out the timing I should be all set.
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