Scratched block cylinder head mating surface (deck)

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Crazymanneil
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Scratched block cylinder head mating surface (deck)

Post by Crazymanneil »

Hey all. Currently re-assembling my (not so) Smart engine - best use of a bank holiday. Putting pistons in i managed to mark the block where the cylinder head goes on. This was basically caused by the piston ring compressor on the soft alloy block.

I am pretty pernickity about these things so maybe I'm overreacting. Though any reccomendations for something I could smear into the scratch to help the gasket seal? JB weld or something?

The scratch goes round the cylinder wall rather than across it. its not that deep or long either so may be ok 'as is' but might as well try something while I have it apart. Its quite far from the steel cylinder liners too so hopefully the combustion area should seal up ok.

Other than that the engines going back together ok. I figured out the timing chain tensioner too and cleaned up the injector seats so another couple of nights should put it together...

N
Smart engined 800cc turbo diesel triumph tiger. 100mpg (imp)
Belfast to Kathmandu overland, 2010/2011 - http://www.suckindiesel.com
Bangkok to Sydney ???
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Diesel Dave
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Re: Scratched block cylinder head mating surface (deck)

Post by Diesel Dave »

I would imaging the marks are pretty close to the bores so should be where the solid rings are in the head gasket.

Do not use JB weld or anything else Epoxy based.

I would get some Hylamar Gold - it's rare but much used in race motors to keep the gasses in place, it will set like concrete where the high temperatures hit it and it's a real pain to remove next time round.

I used to use it on 2 strokes when running without gaskets.

Dave
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Crazymanneil
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Re: Scratched block cylinder head mating surface (deck)

Post by Crazymanneil »

Cheers Dave.

The mark is actually a bit back from the bores. The engine is alloy with steel liners but the mark is on the alloy bit. I am hoping that the head gasket will seal on the liner anyway so should not be a big deal. However, I will get some of this hylamar stuff just to skim into the scratch.

Found out today I need new big end cap bolts too so will have to wait on them coming anyway.

N
Smart engined 800cc turbo diesel triumph tiger. 100mpg (imp)
Belfast to Kathmandu overland, 2010/2011 - http://www.suckindiesel.com
Bangkok to Sydney ???
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andrewaust
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Re: Scratched block cylinder head mating surface (deck)

Post by andrewaust »

Same here, I also recommend "Hylamar & Hylamar Gold" personally used on all diesel & petrol engine rebuilds, the blue stuff that works. Don't sniff the fumes for tooooooo long :shock: :lol:

Just make sure you don't go tooooo silly and spray to much into the bores. The rings will scrape it away OK, but prevention is better then cure.


A;)
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