Head Problems - What's the Problem

leadpot

leadpot

Senior Member
Why is there so many problems with the cylinder head on an A. Is it an engineering/design problem that there are so many issues when dealing with the A's heads and gaskets. Seems that this should be one of the simplest item to install without problems - 2 flat surfaces bolted together. But there are constant conversations about the right gasket, tips, tricks & torquing techniques to prevent problems. As a fairly new, first time owner (4 years) I dread the day I will have to put a wrench to my stock engine. Have rebuilt several engines over the years (V8's) and never had a problem with a head or gasket. Just curious.
 
Brent is right, if you think about it, the bore of our A's is almost 4" and 202 cu.in's while the next engine Ford designed the 221 cu.in. V8 had a bore of a little bigger than 3''s. The engineers added 50% more head bolts, up'd the compression a little and with a 50% increase in head bolts it still wasn't enough. The engineers added another 3 more head bolts before their creation stopped blowing head gaskets on a regular basis. The guys running at the lakes and Bonneville with their flathead Model A/B engines, add additional bosses to the block along with o-ringing the block and sometimes the head with steel O-rings to keep a head gasket from blowing during a pass.
 
Not enough bolts for that thin of a head. If the head was a over head like modern engines the gaskets would hold better. A thicker head would not give between the bolts as much.
 
A cylinder head is a long, thin section that is easily warped by incorrect torqueing or bolting to an unflat surface. Most heads that I pull off need to be resurfaced and require .008 to .018 to make true. Checking with a carpenter square and a flash light is not going to cut it. I use a precision straight edge and a .002 feeler gauge to check, if they fail it is off to the rotary broach for re surfacing.
 
Just use good shop practice and a good quality gasket such as a Best 509c or a Best 509g. Put it together with a thin film of a copper coating gasket sealer. Follow proper torquing sequence just as you when working on your other engines. Most of the problems you read about are not the norm. We don't see any posts about the all of the successful head gasket installations.
 
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I always use a copper gasket with a liberal coat of spray Copper coat. I warm up the engine for about 15 minutes, turn it off and retorque to 55lbs.
Works every time.
 
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