Cracks in the head!!

Actually Red the billeted blocks you sent are +0.20mm already. Wasn't going to fuck with them beauties, rather play with the old blocks. My engineering mate reckon lowering the centre blocks was a better option than decking the top face. Also suggested maybe using your blocks on the ends and the old blocks in the centre. I'll give him a call and run that one past him again. I'm heading back to Perth in a couple of weeks so could be done then. Head still has cracks in the corners so still not happy with it, would dearly love to get another in good condition then sometime in the future send the original it to you to sort out. Don't trust no fucker in Perth anymore with my Laverda stuff!!
 
okay, if you already have the 0.20mm offset blocks then I do not see an issue with facing the top face so it is flat
it is what the offset blocks are made for, everything else stays in exact same relationship except for the camshaft center which raises by 0.20mm

if it takes more then 0.20mm to clean up then I can swap you a set of 0.40mm offset blocks, have 3 sets of those in stock

 
Hi All,

Back to head cracks...

I need some 'how to temporarily bodge it' tips please. Goal is to seal the oil leak.

Getting the Jota ready for Breganze in July, but I have no time for a proper fix before then. Any fix will have to be in situ.

The head has previously has Loctite 290 into the crack - it didn't work though, despite thourough cleaning/flushing of the crack. The 290 soaked in alright, just wasn't man enough.

Ideas?

Also, does the crack propogate further and further, or, self limit? Should I leave the Jota at home and go on the Blackbird?

Cheers.

Paul H

jota+head+crack+may+2014+%25284%2529.JPG
 
Paul,

A good quality, high temperature silicone gasket goo may work. 
I've used it in the past as a temporary fix for an oil leak from a hairline crack in the inner alternator cover.
Applied the sealant as a thick seam over the crack.    It lasted for a long time.

Tom
 
How much does it leak from there?  Much?    Breganze on a Honda?  Hmm...
 
Thanks for the suggstions chaps.

There is a suprising amount of oil coming out. to the extent that the front of the engine gets so wet that it runs around the side and flies back onto my legs. There seems to be a lot of crancase pressure behind the oil..... I'll open another thread.

I'm thinking of trying to get Araldite into the crack (by warming it - gets nice and runny, but maybe not runny enough). Then bolstering that with an araldite external seal over the wider area.

The silicone ide is good also.

Paul

 
Whichever you decide to use, there will be specific grades of Araldite or silicone designed for that job.
I wouldn't just use bog standard stuff without doing a bit of digging to see if there is a specific grade somewhere for that type of problem.
 
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