Head Gaskets.

François has had two head gaskets fail on him with 365 heads, and we've been working on finding a replacement that works. We're still collecting data, and if you have anything to add, please e-mail me. Collecting this information will help others before they encounter the same problems, and may force the suppliers to take note and make changes with their products. No one wants to pull a head again on a V-12 Ferrari engine because of inferior head gaskets!
Ferrari head gaskets
There are three different designs of head gaskets available out there, but we've had two of them fail on us.
original headgasket
Here's a gasket that cam off of a 365GTC/4. It looks original, and does not have a silicone o-ring type gasket found on some of the modern head gaskets.
rope trick
Upon closer inspection, however, we found an old engine builder's trick at work on this gasket. Yarn was laid on top of this head gasket surrounding all the water passages. François was taught this trick at the factory, and I've seen him use this technique on gaskets before the silicone o-rings were introduced in the modern head gaskets. Seeing this yarn has led us to believe this engine may have been apart once before. Whoever assembled this head knew the same tricks as François, whether it was at the factory or in some other shop is anyone's guess.
failed head gasket
This gasket was purchased from an Italian manufacturer. It measured, and looked very similar to the "original" one pictured previously.
gasket crush
It, however, failed to seal the water passages when the head was torqued down. There was not enough "crush" between the cylinder walls and the gasket to seal the water passages. Ferrari cylinder walls sit a couple thousands proud of the block deck, and crush the head gaskets a little more at the gasket's fire ring. The fiber portion of the gaskets should seal sufficiently once the cylinder walls seal against the steel rings. These Italian gaskets did not. After the first failure, we tried spraying a second set with spray RTV with little improvement. The coolant still leaked out between the head and the block without any pressure to the system.
another failed gasket
On another car, a 365GTB/4 Daytona, a recently installed headgasket failed. This gasket is another design with a modern o-ring impregnated around the water passages. The symptom was finding water in the oil.
o-ring detail
This gasket is widely available from parts suppliers in the States, and I've seen them before at other shops, but we're surprised this one failed. You can see the RTV residue on this gasket along with the flattened silicone o-ring that was supposed to seal the water from the oil passages. François has probably installed thousands of gaskets, so i would doubt operator error in this failure. Besides, if there was a mistake in the installation, the gasket would not have taken several months to fail.
gasket from Oz
A third gasket was purchased to try on our 365 engines. This gasket comes from Australia and although has the silicone o-ring, its seal is more thorough.
oz gasket
The silicone o-ring in this gasket surrounds more of the water passages, and may do a better job at sealing the head. We've installed this gasket on the C/4 and so far, have not seen any leaks. The Daytona is next, and we'll see how things go. Hopefully we'll get to the bottom of this and will find a gasket we can all rely on!

Back to tips.