Leaking head gasket
 

I’ve got a 1954 Mainline with a 239 Yblock. Over the winter, I had the heads and deck machined. Yesterday, I finished the assembly, started her up and let her run for about 15 seconds. Afterwards, I noticed coolant weeping out of the head gasket on the drivers side above the oil filter.

Additional information that might be useful: I used the Felpro embossed metal head gaskets (dry) and head bolts were torqued to 75ft-lbs (spec) torqued in a clockwise pattern from center out. I have no leaks anywhere else.

I’m curious what advice this group has for my next steps.

Re: Leaking head gasket
 

Just replaced the head gaskets on my 56 292 with fel pro head gaskets after 43 yrs of driving. Even though fel pro states there is no need for any sealent I’ve always sprayed my gaskets with heat resistance silver spray paint and installed them while they are still tacky per the recommendation of a ford mechanics back in the 60s. As far as advise my first thought would be to retighten the head bolts around that cylinder to 80-85 lbs. if it’s still leaking you might be looking at a cracked head or block.Iam assuming it didn’t leak prior to you working on the motor which would probably indicate a head gasket issue.

Re: Leaking head gasket
 

The engine was a mess before the rebuild so it’s hard to know what was wrong. I had extremely low compression and I blamed it on the valves but the gaskets were probably bad too. The valves, springs, and seats were all replaced and the block and heads were checked for cracks before machining. Obviously, I hope that’s not an issue.

I’ve never heard about using silver spray paint on the head gaskets. Is it too late to do that to these gaskets since they have already been tightened?

One other thing… I didn’t oil the threads of the head bolts before tightening and I see some threads recommend that. Should that matter?

Re: Leaking head gasket
 

Here’s the ARP article on lubes and torque. Remember they’re selling a product, but I’m confident they don’t miss represent the facts. You can draw your own conclusions. I’ve had water leaks in that exact same place that went away when re torqued. Careful about short runs when breaking the cam in.

https://arp-bolts.com/p/technical.ph...ver%20possible.

Re: Leaking head gasket
 

Were the head gaskets properly installed? Square tabs go in front.

Re: Leaking head gasket
 

Yes. This is my first time rebuilding an engine like this, so I was very careful about the orientation of the gasket.

Re: Leaking head gasket
 

In a situation such as this, it is best to go to someone who has all of the correct current tech answers -

http://forums.y-blocksforever.com/Topic162183-1.aspx

I would also ask his (TED EATON) advice on any sealer used on a composite gasket.

As for the leak, it may appear as only exterior but it may also may be being ingested into the coolant (exhaust gases) and/or engine oil. The Y-BLOCK is tough but it ain't that tough.

Used head bolts need to have the threads completely cleaned and the threaded holes chased with a thread chaser/tap so as to able to arrive at correct torque values. As for a lubricant, see what ARP and TED EATON recommend.

Remember also that there are short/long head bolts and they have to be installed in correct sequence.

Re: Leaking head gasket
 

I've never heard of using paint but I did use copper sealant when I assembled my 239.
https://www.amazon.com/Permatex-8069...663473582&th=1

Re: Leaking head gasket
 

Yep, I use that copper sealant too. Never had a problem.

Re: Leaking head gasket
 

Embossed metal head gaskets - are these also called steel shim head gaskets. Even though both surfaces were machined, you may have better luck with the thicker gaskets, which the aforementioned Ted Eaton suggests. And the ones from Best Gaskets which he also suggests..

Re: Leaking head gasket
 

Paul is correct; however, if your block hasn't been zero-decked, the added compressed thickness of the composite gaskets could put your quench beyond .060, which is not a good thing.