PROBLEM: I have coolant leaking past the cylinder head studs in my new engine. Yes I have done a search. Past articles gave me the idea I used the wrong sealer (see HISTORY OF PROBLEM).

ENGINE: Brand new 4 bolt 350 block. New AFR 190cc heads. ARP cylinder studs. Weiand intake with 142 blower. I am using new head gaskets (don't remember which ones but they are the ones AFR recommended). Torquing everything down to 67 ft/pnds (forgot how I came up with that number)

HISTORY OF THE PROBLEM: When I first built the engine I used the wrong sealer on the studs. I used hardening sealer. When it leaked it wasn't a shock. Stripped everything off and used non-hardening sealer from ARP. Still leaked. Realizing I didn't properly clean the threads of the old sealer (duh) I stripped the engine down AGAIN. This time I cleaned out the threads and used the correct sealer. I just cranked it and let it run for 20 minutes. Still leaking.

INSULT TO INGURY: Last time I went to put the water neck on I stripped the threads out of one of the bolt holes. Got it heli-coiled and put sealer on it. Leaked like a beast today.

POSITIVES: I'm getting awesome at setting valves and timing the distributor.

SOLUTION TO PROBLEM: Anybody!?!?!?!?!

 

I have never in my life seen a motor with head studs that didn't leak; no matter who put it together, or what they used on the threads.

You might want to try taking them out one at a time, and putting Loctite PST or whatever they call it now, it's their thread sealer with Teflon, don't try to get away with hardware store pipe dope, on the threads where they go into the block, and under the washers.

 

I hear what you're saying but this seems excessive. After running the engine for only twenty minutes I can see coolant bubbling up past some bolts. I used ARP's non hardening thread sealer on the threads but I didn't really do anything on the washers (at least not the last time I bolted it all back together) except assembly lube trying to keep the torque readings correct. I guess I will get the Loctite and see if it works better.

Glen

 

i use PST on the threads and under the nut, washer, or bolt head