Whats the minimum head height for a 2wd i have just removed head and its measuring at 138.5 can it be skimmed any more pistons have little cut out marks

 

not sure - i know its 138.something

 

Did you not get the text I sent ya??

 

Ford manual says 138.68 but can be less than that, slight valve contact is normal swell don't think I've ever had standard pistons that didn't have marks on!!! Obviously get it checked but if it's not warped then only needs a clean up skim

 

so whats the height a new head comes with?

 

Ermmm pass lol not at home at the mo so can't check but from memory it's over 139mm

 

I think the standard thickness a ford head came with was 139mm. Im sure someone can clarify for sure though as im not 100% sure!!

 

what head gasket are you using, and is it possible to get a slightly thicker one??

As for skimming the head again, if there weren't any problems prior to removing it, it should only want cleaning up and shouldn't need a proper skim anyway.

 

138.68mm.

the problem isn't just valve contact if you go thinner, there is also a risk of the chambers dropping out as there isn't enough to hold them in if you go below that.

 

Was going to use a group a. The head gasket went hence i have sent it for pressure test and check if warped. It supposidly had a rebuilt head about a year ago and hasnt over heated so i guess it will be ok. The engineering shop dont have data on how low you can go.It might not need a skim but just wanted advise as if it did i dont know if it was at limit already and didnt want to have all the work donw to find it too low.

 

Sorry Steve phone died and didnt get text till i got home and put on charge after i posted.

Thanks for the information.

So if it needs a skim i should be ok with a thicker gasket which type exactly.

Got to the bottom of the copper seal. Matey that owned it before me put copper k sealer as a cheap fix to keep it going!!!! till fixed

Cheers

Ian

 

A "chamber" drops out!!
Would have no need to worry about the HG if the combustion chamber dropped as the head would have melted for this to happen.
The problem is the retention of the valves seats, mostly the exhaust seat this can come out if skimmed too much, but can be used well past official limit, don't forget ford didn't really care that much about using what's good as the customer would be paying the bill.
Get the head on the bench and check it with a torch to see if warped, then measure amount if it is, from what you say in the other post pay particular attention to the front of the head due to the loose studs/nuts, this is a classic sign of warpage, any half decent machine shop will know how far you can go.
When refitting with a group a you MUST let the gasket rest for at least 4 hours, preferably overnight, and torque up to 120lbft, in 30lbft stages, but take out studs and depth check, cut if necessary, clean out old congealed oil from bottom of holes, and if tappets were noisy, take apart and clean out as ideal time to do it.
tabetha

 

138.68, but many are used with a lower thickness

lots of useful info here https://passionford.com/forum/techni...thickness.html

 

As above!! i know of heads used before well below the stated and they have run fine!! Obviously if your going for a specific or mental spec then the amount skimmed off can affect the build but then you would probably want to rebuild the bottom end too if you were doing that, in reguards to using another gasket mate the metal thicker ones you would need to get the block checked and possibly skimmed aswell to make sure its true or it will leak.

So is the gasket ok then?! obviously the copper ness is due to the sealant he used, but you need to work out what was causing the water/oil mix and if the HG is fine hopefully it'll be the head, if not could still be a block problem.

 

the more you skim the head, the more chance of encountering problems with the valve seats.

i'd hate to spend X amount of a rebuilt motor only to risk a thin head and destroy the lot. give yourself the best chance and get the thickest head you can find/ afford