ET: Engine (Twin) porous cylinder head

Vincent Brake

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Series B

Well its (uk: she's) ready, done 300 km, but i see the rear head ( it was at suspect when assembled, but Hey...) leaks a bit nice black oil just under the exhaust surroundings, now i guess theres a lot of stuff arround, to seal it up, or?

Any recommendings? apart from welding....
 

davidd

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I have not done this, but Loctite has been used successfully. Denny Delzer had a leak in his Godet Egli cylinder head. Patrick came over to check it and sealed it with Loctite according to Denny. I believe it was on the intake side of the head in that case.

David
 

timetraveller

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Vincent, before getting too worried just have a careful look at where the oil is coming from. I have known a leak to show up near to where you are finding oil that has come down the exhaust valve guide, into the exhaust port and then leaked out of the joint where the exhaust pipe fits into the cylinder head. Clean it off really thoroughly and then do a short run and have a look again. It might not be a porous casting, just a poor fitting or loose valve guide. Good luck.
 

vibrac

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If its porous you will be in illustrious company! Bananaman will tell you its why the Black Shadow is Black
 

Vincent Brake

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oh Bugger. and Yes saw it was porous when i did the valves etc. learing all the time. now i either sell it and put the orignal on(but with collapsed fixing bolt holes, due to to high torque) but i like to save it as i did ampco 45 valve guides in, and want to know how they live the life...
some one says locktite 190

I know now it is leaking from the inlet all though the exhaust, as she smokes a bit too. in the pic is oil form the rocker tunnel, into exhaust, and further down to the outside. Next winters job, as i want to ride a bit....
2018-05-15 17.54.36.jpg
 

kettlrj

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It is common practice to impregnate Aluminium castings in the automotive industry with a resin that seals any porosity in the casting. If you Google - casting impregnation services you should be able to find someone near to you that can do the job. I had both my heads done via a friendly foundry who put them through with a batch of their castings. Now the b*****er just leaks from somewhere else. Oil is guaranteed to find its way to where it is not wanted and stay away from the places it is supposed to lubricate. Sod's law I am afraid.
 
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