Weeping head studs

[Rudolph]

I had my 1942 Mercury rebult by a well-known shop but it leaked water from the head studs, wile re torquing the head i removed each stud one by one and applied a cylinder head stud sealer to the threads, I ran the engine on water for a couple of months but now I have Castrol antifreeze it weeps ever so slightly around a few of them when the engine is cold, no bubbles in the radiator or oil, no water in the oil, has Best Gastkets head gaskets should I ignore it? Or put some poo in the raidator?

[Rudolph]

Actually its weeping all round the gasket

[Rudolph]

I am going to replace the gaskets and give them some head gasket spray, i cannot get them off tho because of the thread sealer on the studs

[Flathead Fever]

If they ran the wrong tap into the block's stud holes, they might have messed up the interference fit threads, The original studs and block threads are an interference fit. The threads are slightly different between the studs and the block, that is what originally made them seal. That happened to me on the first flathead I did and that happened to a neighbor too. Even with the old standby, Permatex non-hardening sealer they leaked. I finally cleaned the holes and the studs really well and put them in with blue Loctite and that sealed the threads. It should not hurt anything since the blue Loctite is made to be removed. Never use the red on anything unless you want to heat it with a torch to break the seal. It is not made to be taken a part.

[3Dueces]

Gee Whizz! It would'nt happen to be from that shop in California?

[Tim Ayers]

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It happens. My new flathead is doing it to. I'd run it a few heat cycle and torque the heads to see if it stops.


If it doesn't, I'm going to run some sodium silicate in the system to help seal things up.

[Rudolph]

I couldn't find any head studs and the shop made some, i put locktite high temperature thread sealer on them but they still leaked, another shop sed put high temperature gasket maker on them, he dose it with the Chevrolet engines

[Pete]

Originally Posted by Rudolph

I had my 1942 Mercury rebult by a well-known shop but it leaked water from the head studs, wile re torquing the head i removed each stud one by one and applied a cylinder head stud sealer to the threads, I ran the engine on water for a couple of months but now I have Castrol antifreeze it weeps ever so slightly around a few of them when the engine is cold, no bubbles in the radiator or oil, no water in the oil, has Best Gastkets head gaskets should I ignore it? Or put some poo in the raidator?

I can tell you what works on a 300 hp flathead circle track
engine and I am quite sure it will work on a street engine.
I lost track of how many engines I have built but I have never had a
weeping stud or weeping gasket.

1 - Use a copper head gasket. Spray both sides with aluminum
paint just before assembly and let paint dry 5 minutes
before installing.
2 - Chase the block threads with a STANDARD tap. Be sure the
hole is ABSOLUTELY clean before assembly. Chase the threads
on both ends of the studs with a standard die nut, EVEN IF THEY
ARE NEW STUDS.
3 - Check each stud to see that it will screw in BY HAND to the
bottom of the hole.
4 - Roll the studs on a flat surface to see that they are not bent.
5 - Take the first stud and generously apply black high temperature
RTV ( NO SUBSTITUTES) to the block thread and screw it in by hand till
till it bottoms. Then, back it up 1/2 turn. Wipe off any excess RTV
around the base of the stud.
6 - Repeat for the rest of the studs.
7 - LET THE BLOCK SIT FOR AT LEAST AN HOUR BEFORE PROCEEDING.
8 - Check the gaskets against BOTH the block and the heads to be sure
there is NO overhang anywhere. The fire ring must end up between two
hard surfaces.
9 - Wipe the fine thread on the studs with an oiled piece of cotton.
DO NOT GET OIL ON ANY OF THE GASKET SURFACES!
10 - Install the gasket and the head. Install a 1/8 thick HARD machine
washer on each stud. Use washers even on cast iron heads.
11 - Install hard high nuts and run down snug. Torque head using standard
sequence in 20 lb increments to 60 ft.lb.
12 - Retorque heads after each heat cycle till no further gain.

[Rudolph]

I will give that a go, I got some Worth high temp black silicon and some VHT head gasket spray, block and heads have been decked studs are new but i need to clean them, I damaged the gaskets so need to get new ones, i hope i can do that tomorrow

[Pete]

Originally Posted by Rudolph

I will give that a go, I got some Worth high temp black silicon and some VHT head gasket spray, block and heads have been decked studs are new but i need to clean them, I damaged the gaskets so need to get new ones, i hope i can do that tomorrow

Forget the "head gasket spray".
Use the paint. Besides all else, it is cheaper.

[Rudolph]

This is the only engine that i haven't used spray on the gaskets and its the 1st one to give trouble

[Phil Gillespie]

Originally Posted by Rudolph

This is the only engine that i haven't used spray on the gaskets and its the 1st one to give trouble

Copper or composite head gaskets????
Composite are a one off and will delaminate when head is removed.
Phil NZ

[19Fordy]

Use a thread chaser, NOT a STANDARD TAP.
Read all this, especially the section about:
TAP LIMITS PRODUCT LIMITS AND CLASS OF THEREAD.
https://www.newmantools.com/taps/taptech.htm#cla

[Rudolph]

The engine was only built a few months ago, threads are really clean, i was able to screw all the studs in my hand, they have Worth silicon on them now

[Flathead Fever]

Originally Posted by Phil Gillespie

Copper or composite head gaskets????
Composite are a one off and will delaminate when head is removed.
Phil NZ

The thig about copper gaskets on a street engine that will be assembled for years is the electrolysis between the copper gaskets and the aluminum heads. Modern Factory engines with aluminum heads use composite gaskets for that reason and they can last 300,000 miles. Also the aluminum heads and cast iron blocks have different expansion rates that the composite gaskets are designed to handle. On a race engine use copper gaskets to handle the high cylinder pressure and on a street engine use the Felpro composites. They come with a sealer on them that activates when they get hot. Edelbrock recommends the Felpros with their new heads. We used them at work on the modern cars with aluminum heads. Look at the old aluminum heads that ran copper gaskets and they are eaten out around the coolant passages. Look at a modern engine with aluminum heads and composites gaskets with over 100,000 miles on them and there will be no sign of corrosion at all.

[Pete]

Originally Posted by Flathead Fever

The thig about copper gaskets on a street engine that will be assembled for years is the electrolysis between the copper gaskets and the aluminum heads. Modern Factory engines with aluminum heads use composite gaskets for that reason and they can last 300,000 miles. Also the aluminum heads and cast iron blocks have different expansion rates that the composite gaskets are designed to handle. On a race engine use copper gaskets to handle the high cylinder pressure and on a street engine use the Felpro composites. They come with a sealer on them that activates when they get hot. Edelbrock recommends the Felpros with their new heads. We used them at work on the modern cars with aluminum heads. Look at the old aluminum heads that ran copper gaskets and they are eaten out around the coolant passages. Look at a modern engine with aluminum heads and composites gaskets with over 100,000 miles on them and there will be no sign of corrosion at all.

Engines that were run with plain tap water will have corosion.
Engines with proper COOLANT will have NO corosion.

[Tinker]

You could run anti-sieve on the threads will do the same thing and less issues. Over time you will be able to remove them too. Torque and run it.



If you are getting no coolant in the oil and compression numbers are solid. Let it ride. Run it. Could be they chased the block with straight taps vs rolled. Over time they will gum up.

I'm assuming they are weeping not pouring out coolant.

I like the spray vht and/or copper spray for gaskets. Fine coat and less mess then a glob of rvt.

[Tinker]

Originally Posted by Flathead Fever

The thig about copper gaskets on a street engine that will be assembled for years is the electrolysis between the copper gaskets and the aluminum heads. Modern Factory engines with aluminum heads use composite gaskets for that reason and they can last 300,000 miles. Also the aluminum heads and cast iron blocks have different expansion rates that the composite gaskets are designed to handle. On a race engine use copper gaskets to handle the high cylinder pressure and on a street engine use the Felpro composites. They come with a sealer on them that activates when they get hot. Edelbrock recommends the Felpros with their new heads. We used them at work on the modern cars with aluminum heads. Look at the old aluminum heads that ran copper gaskets and they are eaten out around the coolant passages. Look at a modern engine with aluminum heads and composites gaskets with over 100,000 miles on them and there will be no sign of corrosion at all.

Ya my thought process has been copper spray for headgaskets. Composite mostly because they are very good. Always with aluminum heads. Copper gaskets only with iron heads. But I've never experienced ill effects other wise, as I'm always messing with things.

[Rudolph]

I just have normal ford truck heads on the Mercury, I got a new set of the best gasket copper fiber type.


I put copper spray on the gaskets of my 1938 motor and that ran antifreeze for meany miles with no problems. Those heads settled down on about the 3rd re torque.

[Ronnieroadster]

Pete excellent description on how to do this. Simple and effective.
Thanks for the info.