blown cylinder head gasket...?

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Jun 2, 2005
well i had a couple of nice (relativelty) trouble free weeks there and then today.... after a 50 or so mile ride down hwy 1 and back i stopped for a burger on the way back to my house and when i rolled up the street all of the suddend i could hear and feel exhaust coming out the side of between the head and barrel. i assume that means the gasket is hosed. a small ammount of oil is coming out as well. aside from replacing the gasket itself what else should i be looking for as a cause for this? thanks, m

850 mk3
Check the head and cylinder mating surfaces with a straight edge and feeler gauge. Look for any raised areas around the bolt holes where the threads might have pulled. Have them milled flat if necessary. Then check the threads in these holes. They may need to be repaired with a thread insert. If the old gasket is solid copper, either anneal it before re-using it or use a "genuine" Norton flame ring/composition gasket (my choice!). DomiRacer re-pop flame ring gaskets can be used, but often have difficulty sealing around the pushrod tubes and intake rocker drain back hole. If these are used, make sure you seal these with a little gasket sealer.

Look closely at your headbolts for signs of necking or stretching. Replace them if necessary. Beware of stainless steel headbolts as some are made from poor alloy and stretch easily. That said, I know of several engines working perfectly well with stainless. Only two I recall with problems.

Re-torque the head after a couple of heat cycles and pay close attention to the long nuts under the exhaust ports.
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