Hey guys so after finally getting a compression tester that works (and $50 later) i've found that number 1 and 2 cylinders have no compression whatsoever... Take the head off and the gasket has blown between number 1 and 2 cylinder....


 
 
 
so what I was wondering is, whats the cause of this??? I torqued the head bolts as specified in the workshop manual after 15-20mins of idle when first assembled... Could this just be a dodgy gasket? The engine has only done 4000km's so I'm a little bit confused... Also, I noticed that there is similar wear in the gasket between cylinder 2 and 3, is this gasket not suitable..?
 
Thanks guys!

Not even thanks for diagnosis?..... 😉

Was the block decked and head faced at rebuild time?

Haha sorry mate just went back through the comments and realised that was your initial diagnosis, thanks   i was a little too busy checking exhaust leaks 
 
Yes the block was decked and the head was faced 4000km's ago at rebuild. I've just remembered something from assembly. My mate who helped me reassembled neglected to use the grease that came with the head bolts when assembling... I've been reading up on the inability to correctly torque down stretch bolts if the correct lubricant isn't used... so i'm thinking..... incorrectly torqued down head which caused the head gasket to be incorrectly compressed, hence allowing for that weak spot to blow? would this be consistent with the 2/3 cylinder barrier about to go aswell???

obsesscort

Haha sorry mate just went back through the comments and realised that was your initial diagnosis, thanks   i was a little too busy checking exhaust leaks 

Yes the block was decked and the head was faced 4000km's ago at rebuild. I've just remembered something from assembly. My mate who helped me reassembled neglected to use the grease that came with the head bolts when assembling... I've been reading up on the inability to correctly torque down stretch bolts if the correct lubricant isn't used... so i'm thinking..... incorrectly torqued down head which caused the head gasket to be incorrectly compressed, hence allowing for that weak spot to blow? would this be consistent with the 2/3 cylinder barrier about to go aswell???

No worries, the unique cylinder cross firing was a giveaway.

Lack of lubricant will cause incorrectly tensioned bolts, make sure you lightly lubricate the thread and under the head of each bolt. Also make sure that the bolt holes and it's threads are clean, running a correct tap down each hole will suffice.

Detonation can be major cause of damaged fire ring too, don't assume anything and recheck your tune after head repairs.

Another thing to check is the head and block surface where the head gasket failed, as combustion may have torched the surface to the point of it needing refacing. If you put the head back on with compromised surface you will blow another gasket in the same spot in a very short time again.

Not sure what you used but also make sure you use quality head gasket !

Cheers

hey RS2000, i've cleaned the block and head surfaces down with carby cleaner and really fine grit sandpaper and block. I've checked the block and head surface and i can't fit a .05mm feeler gauge anywhere with the bar from front of block to rear of block, so thats looking OK. I also used a industrial vac and got anything foreign out of all the bolt holes and piston bores (even though i covered this with a rag whenever possible).
 
 
are you referring to timing when you refer to checking the "tune" after installation is complete?
 
i might just take this time to add some keywords to this post for future sufferers....
correctly installing head gasket
correctly installing head bolts
problems with compression
 
 
thanks again for your replies guys

I'm with Rs2000.
Do a compression test for a breached gasket.
If its not timing then it's likely hot or lean.
Is plug colour ok ?
Advance hose ok?

oops - sorry - i skipped to the end

obsesscort

hey RS2000, i've cleaned the block and head surfaces down with carby cleaner and really fine grit sandpaper and block. I've checked the block and head surface and i can't fit a .05mm feeler gauge anywhere with the bar from front of block to rear of block, so thats looking OK. I also used a industrial vac and got anything foreign out of all the bolt holes and piston bores (even though i covered this with a rag whenever possible).


are you referring to timing when you refer to checking the "tune" after installation is complete?

i might just take this time to add some keywords to this post for future sufferers....
correctly installing head gasket
correctly installing head bolts
problems with compression


thanks again for your replies guys

You obviously got away without head and block surface damage, cast iron is forgiving, had it been an alloy head would have been a decent crater there. 
Sorry but vacuming the bolt holes is not good enough. Tap is the only way to make sure the threads are clean. Sounds like you didnt use a tap at rebuild either?
Do yourself a favour and buy a tap, they not expensive.
 
Yes definately recheck your tune- mixtures and timing, making sure the advance curve, and total advance is suitable for your setup.
 
Cheers
 

Thanks mate will do in the future. Thanks for your advice and prompt response