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Nearly done!

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Robbo:
I noticed my trousers were oily on one side today and the block seems quite oily. It looks like its not coming from the head (and I think I the head gasket had gone it would be quite apparent?) but from number 3 downpipe area. I've got new pipes on order anyway so I'll do some investigation when I take the old ones off.

Anyone had any experience of this or any idea what it might be before I investigate further?

Waggles:
Couldn't see from your list of work done whether you have done any engine work? my guess would be its an oil way leaking, would suggest you check asap and before any more ...er ..... high speed rides, if it is an oil way the cam could become oil starved and ........ well y'know. seriously hope I am wrong as it could mean the head having to come off = engine out, but better safe than sorry. To be fair though cam problems are usually caused by oil way blockage rather than leaking, but leaks must reduce oil pressure if they are bad enough.

Another possibility would be the cam cover gasket ot tappet cover seal, that should be easy to see though. Just how bad is leak?

UKROBK7:
If its a 750 it could be the  "pucks" that seal the large holes under the cam towers.  Before I stripped my engine down it was leaking out of the head fin area between number 2 and 3 pipes.  Found these seals had deteriorated due to age.

Rob

UK Pete:
A real common leak problem on these F2's occurrs when the 4 main  studs  in the middle that hold the head down let oil through, if you look at a parts diagram for F2 you will see these four have a copper washer and a dome nut to stop the oil seeping down the stud, these four studs are open to the elements, they can be seen through the fins hence they are always the rusty ones when you take it apart
Another place common for leaks is as mentioned the cam pucks
A place where oil leaks often get overlooked is the cam tower holding down studs, these are drilled straight though and so if not sealed when reinstalled will let oil in to the spark plug area which will eventually work its way down
Then there is the problem of the head gasket original F2 gaskets have a sealant built in to the gasket, the aftermarket ones have not, i did what K2/K6 does and i sealed my gaskets down with hylomar which can be bought in spray cans
There is also the simple rev counter seal leak the oil will often leak from hear i know cause mine did
Your problem is robin that with all the info in the world it is a rea;l pain in the arse to fix any leak on these cause the engine has to come out even if you want to change the rocker gasket ,
Pete

Robbo:
I took the tappet covers off and checked for oil - they all seemed to be lubricated ok, I know it's not the best way to check but it's a start. I cleaned it up and ran it for a bit, after about 10 mins a little drip hit the floor and it came from the number 3 downpipe, where it had dripped from the number 3 exhaust pipe joint at the head. The cam cover is all clean as are the spark plug recesses as far as I can tell (I stuck a rag down to check for oil - lots of shit, no oil).

I am changing the exhaust anyway so I will get it up on my mates ramp and have a good look around. Taking the engine out is a last resort as I have a slipped disk currently and no way of getting it out apart from humping it out by hand - that and I am a bit weary of taking it out incase I break something in the doing of it. I know I probably should but....

If it is originating from the exhaust joint, any idea of the causes? I have read all of the above replies and will investigate further. Hopefully it's something I can do in frame otherwise I'll have to bite the bullet (if I do that I may as well go the whole hog - re-seat the valves, polish the ports and all the rest of it which will mean no bike for the summer).

On a side note I checked the plugs, 1 was black, 2+3 were normal, 4 was grey (too lean) pipe 4 is also much hotter than the rest. They are all jetted the same, is this to do with balancing the carbs as I thought I had done a pretty good job by eye and a home made feeler guage. Might be time to get vacuum gauges on the go?

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