French flathead, stud kit with Offy heads, torqued to specs. Stud kit had sealer on the threads when installed. Got engine running today, and as temps climbed I had coolant seepage coming up between the threads and the nuts on two of the studs on both heads. Oddly enought they are the same studs positionally on the head. I did retorque, but they still seem to leak on both heads. Seep is the better word. Its not like a hole in a bucket. When I installed the copper head gaskets I did spray them with sealer as well on both sides before installing as the manufacturer suggested. Not getting coolant into the oil, like eletricity and water it seems to follow the path of least resistance. It was suggested to try some stop leak in the coolant to help seal that up. I know its a suggestion and it has some validity to it, but I prefer to find the cause and fix it correctly. Any one experience this with their flatheads?
just run a few more heat cycles through it. let cool off totally with alum heads then re torque. nothing wrong with some stop leak added as well.
J ripper's right. The ideal thing to have done is dry start the engine and let the heads get hot to the touch. Just about where you can stand to touch them. Shut it off and retorque. I would stay away from adding any bars-leak or anything like that. If it keeps up. Pull the heads and studs. Use the prematex black sealant on the threads and around the studs once in place before you install the heads, put some Indian Head shellac on both sides of the head gaskets and repeat the install process including the dry start. I went through the same issues when I did my first Flatty years ago. This stopped my leaks and have done a dozen or more since then with good results~! Not much of a fan though on the stops leak stuff. __________________________________ Hey don't worry I'll respect you in the morning!
Is it a safe guess that two of the studs are the top center one on each head? That one's an easy and certain fix -- during ***embly. Unlike the domestic Ford/Mercury blocks in which the upper stud or bolt in the center of each cylinder head screws into threads that are contained in the deck, the stud in a French block p***es through the deck (and the water jacket) and screws into the top of the siamesed exhaust runner. This requires a longer stud and an O-ring for each side. (These are included in the parts kit thats provided with each new French block from San Francisco Flatheads.) For reference, the O-rings are ASTI No. 012 (1/2-inch OD, 3/8-inch ID, 1/16-inch section). Before installation, give the stud a liberal coating of Permatex or a comparable sealant. Screw the stud in tight and install an O-ring, down past the upper threads. Install the gasket and push the O-ring down into position to form a water-tight seal. Hope this helps . . . Mike
Wow av8 - the knowledge on the HAMB never ceases to amaze me. I don't know if Ken is being too modest, but he should post a pic of what surrounds the French flatty - it's a killer hot rod. C'mon Ken - post pix....
The leakers are the following. Looking at the head on the p***enger side, by the distributor there is one on the top, then one below that. That one is seeping. The second is to the left, where you have three in a row, its the third one on the bottom. Same on both sides. I really dread having to drain the block and pull the heads to fix this, but if I have to. Will see what it does tomorrow. Even if I could pull the studs, I still have to drain the block, and if I have to do that might as well yankem.
Man O-Rings now?! LOL. Well we will see. I appreciate the time to download those pics to show what you were speaking of. I did put sealer around the studs, mabey I wasnt liberal enough. Well I cant be liberal so that could explain that. Definitley let it cure before I put collant in.
J Ripper has it right, I have helped my dad build these motors and built them myself since about 1962 and every one I have ever put together with studs had a little seppage at first, I am pretty sure the heat cycles would do the trick, but I always throw in a can of sealer for good measure, it never hurt a thing.
as stated earlier. running with no water at first a few times really helps. my engine i just did for my roadster seeped water for a few days. it will seal up. just be patient..
Our 8BA did the same thing, after a few heat cycles and trips......it is now dry. Don't fret about it.
The O rings and chamfered washers will do the job. This was in a tech thread long ago and it is a simple fix.
Just to give an update, the driver side seepers stopped, and gained two different ones, but not to the same degree. The p***enger side two stayed the same, added minor ones on two others. Ran engine and retorqued. If the others dont improve will just pull the head and redo them. Thanks all for the help and support
The turds I speek of are the Bars-Leak seal tabs. It seems like alot of the race engines I build seep water up the studs. Toss in a couple of turds and the problem is solved. Not only will it stop your leak but it will lube those spensive water pumps too !! >>>>.
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