FOLLOW-UP FOR DEL/SALMONEYE: BLOWN HEAD GASKET

Somethin' awefully suspicious about them comp readings. #4 at 90 lbs when others at 135? What did a wet test on #4 tell you? Wouldn't bother with a wet test on other 3.

A difference that great - we're talkin' 45 pounds or 50 PERCENT- might spell a thrown rod/broken piston/broken ring for you in the future IF you don't already have a broken ring. 90 pounds is also the minimum spec compression according to Ford recommendations AND though I don't have my manual with me I think you aren't supposed to have more than 10% difference between comps.

I'm hard pressed to believe that you have such admirable compression in #1-3 without having it in #4 UNLESS you have a problem in #4. Hopefully it ain't more than a stuck/improperly adjusted valve.

He is now ready to replace the head...

I think ;-)

Salmoneye, The Often Wrong

I would go with all new head bolts...Not studs and nuts...

It just makes it easier to remove the head if you have to in the future...It can be achieved with removing the hood and tank...

But that is just me...

With the correct torque sequence you can bring all but the extreme worst case warped head back to flat and seal...