Blown head gasket?
 

OK after much thought, I've pulled my engine out to investigate the noise (see engine problems, parts 1,2 and 3!) that started after my roller rocker came off and the engine started backfiring through the carb.
I've removed the sump, stud girdle, oil pump and main caps and can find nothing wrong (apart from a leaking rear seal which I will address) everything seems smooth, with no undue wear, the bores are fine and the piston skirts are intact.
When I removed the heads (world windsor sr in ali with ARP studs) again there seemed to be no problem. The only thing that seemed slightly unusual was that the L/H head (the one where the rocker came off) lifted off straight away, while the unaffected head seemed to be much more difficult to get away from the gasket. Is this a sign of a blown head gasket? I couldn't see any signs of the gasket being blown, but the I don't really know what I'm looking for.
I didn't see any signs of water in the oil or oil in the water when I drained them.
Thanks guys.
Simon

Hi Simon,

Don't envy your situation at all, but can sympathise - my daily driver (SAAB 9-5) just died - electronic fault apparently :CRY: - sounds like it could be expensive!


As far as yours goes, you would only get water in the oil or vise versa if the gasket blew between these two points - if it blows between the combustion chamber and one of these you will not have the same effect but blow oil or water out of the exhaust.

Sounds to me like you may have blown the gasket between the combustion chamber and out to atmosphere (edge of cylinder head).
When that rocker came off and the exhaust valve (it was exhaust wasn't it??) couldn't open - the compressed gasses had to go somewhere and they shot out a weak spot in the head gasket.
This could sound (although I'm not sure) like a slightly blown manifold gasket which would be like a "ticking" sound - which could be the sound you are hearing :confused: :confused:

It's a possibility - and not an expensive fix, but would be difficult to notice, I would think, by looking at the gasket (unless it had been run for a few months like this - which yours hasn't).

As to whether the head would come off easier or not - I really don't know, and doubt it as it would need to affect the whole gasket area - fairly unlikely I would suggest - unless someone else knows better????

Good luck

GUMBALL UK (Sean)