zetec head gasket issues

[FE07]

Since we seem to be having a lot of recent Zetec issues/discussion I thought I'd add a problem I'm having with mine.

 

Seems I've blown a 2nd head gasket. Engine was last rebuilt maybe 1,000 miles ago (which is about 20 months ago in Caterham 7 time). Maybe tracked once over that time. Ran well when I first got it back.

 

As last time- it's leaking exhaust gas into the overflow bottle which then pressurizes/spits and then overflows. No oil mixing into the water jacket.

 

Has a Cometic gasket and ARP head studs. Not sure the compression it's running.

 

It was suggested to me (not by the builder) that the issue could be related to the ARP studs and the need to re-torque them. Looking at the ARP and Cometic websites- they both say there is no need to re-torque either the studs or gasket.

 

Anyone else had similar issues with head gaskets on their Zetec?? Looking for any other potential causes to look out for when rebuilt.

 

Thanks all,

 

Jim

[James A]

Jim, I've used Cometic gaskets and ARP studs on street engines and race engines and have done a number of rebuilds and had no issue, here are some things I do on each rebuild though:

-Deck the head and block to insure they are flat and have the correct surface finish.

-Use the ARP thread lube when assembling, use it sparingly

-Use the recommended 3 stage tightening sequence and absolutely follow the correct torque order

-Once the head studs are torqued I walk away and recheck the following day and proceed with the rebuild

-ARP has a stretch limit for their head studs, once they have a permanent set beyond a certain point don't reuse the studs they can yield, follow ARP recommendations

-Although I don't use this, some very experienced builders recommend copper-kote be sprayed on the gasket surfaces

-Always chase the threads in the block, if a head stud does not seat by hand all the way there are a number of issues that can occur

-Make sure the threads in the block are cleaned out of all liquids and particles and use the ARP thread lube sparingly

-Insure the washers and nut surfaces are smooth with no abrasions

I'm sure others can add to this list, good luck.

[1turbofocus]

At first ( year 2000 ) we has issues with head gaskets on the Zetec , one thing we found was the need to TQ then 6-8 times , you can TQ then 1-2 times and nothing moves on the 2nd TQ but the 3-4 TQ we get 1-4 +/- that move and we have found this to be true more then you think

 

That and went to using the Ford Zetec head gasket and we have made as much as 723 whp with a Zetec and no blown HG sense we found those 2 things

 

Tin