Hey fellas- needing a little help. Had a stroke a few months back and decided, as part of my "get back with the program" to finish building my 1949 Ford pickup. I had a good 350 in the shop, been all machined and everything, so I decided to just use it cause I had it. Don't know anything about the motor, except it was all fresh imternals etc. Well, just to make sure of it, I had a friend come over and we tore it apart, regasketed everything, and re***embled it. Now, I'm no pro, but building a stock (pretty much) sbc is pretty straightforward. Got it in the truck and got everything hooked up, started putting fluids in it and noticed I had a very slight water leak back by #8. Can't really tell where it's coming from, but it's dripping pretty consistent albeit quite slowly. I read someplace that I should have put some sort of sealant on the head bolts (ARP) before ****oning it up. I did not. 1. Could this be the problem, even though the motor has not even been started? 2. Can I pull the bolts individually and fix this? 3. If this is not the problem, any guesses? Pretty stock rebuild, Felpro gaskets etc. thanks-
You do need sealant on the threads, the head bolts do go into the water. Hopefully that is what it is and an easy fix, I'd pull the plugs to make sure water hasn't gone into a cylinder, spin the motor by hand to be safe. I admire your resolve and therapy, its time to double down.
X2 on the head bolts not reaching the water jacket. The ARP thread goo is used to lubricate the threads so you get an accurate torque setting on the bolts, not to seal them. Did you RTV silicone the intake gasket around the water ports front and rear before setting the intake down?
Same here but I did have one leak at fill up by forgetting to put some around the water ports before installing the intake. It puddled on the head/intake and ran down the back of the block.
Just to be the devil's advocate, wouldn't putting a sealer on the head bolts affect torquing them at the same setting? I would like to know myself. At the same time, I haven't used any thread sealer on any of my close to stock rebuilds and haven't had a problem. I've reused original head bolts and used the new one-time use stretch head bolts.
Thank you all for your responses- I did use silicon on the manifold, so I'm thinking that's ok unless I just fouled up someplace. But just to confirm, water can find its way out via these unsealed head bolts even when the motor is not running, under no pressurization of any kind? I will pull the bolts and seal them, hopefully that is the problem and I can get this rig on the road this summer-
yeah, water can seep around the head bolt threads, and get into the crankcase or drip on the floor even if is not running. I always put thread sealer on the head bolts. And make sure some gets under the bolt head, too. And I use aviation permatex on the intake gaskets around the water ports, but RTV on the ends of the manifold, where it meets the block (I dont' use the rubber end seals)
Probably ought to put a mirror behind the manifold at the head and take a look .Water could be running down under the edge of the head and look like it's from the head. Check the torque on the head bolts. Also grab a long 9/16 box wrench , and herc on the back two manifold bolts. Yes, you can seal and re-torque one bolt at a time, but I doubt that's the problem, unless they're really loose. Then I'd be suspect of the whole program.
Of course you will need to drain the block first. And it could be a cracked head. There is a water p***age between the head bolts under the spark plug. Then older heads are cast thicker in this area, newer not so much.
pressurize the system - that will exagerate the leak and maybe you can see where it is coming from instead of guessing
I have had an SBC head bolt weep like that as well. It was a small but consistent leak, I have used permatx thread sealer on all SBC headbolts since then.
If you have access to a pressure tester that would be a way to find it. Some parts stores loan or rent them. I use Zecol Mend***e in engines. It seals leaks but doesn't plug heater cores. It should cure any bolt leaks without having to remove them.
I wasn't thinking about head gaskets when I first read your post. Did you replace them too? Was the deck machined? How about the head surface? How smooth were the surfaces? What type of head gaskets? Torqued in 3 steps, per pattern? Head bolts dry? Oiled? Lots of questions, but hard doing this over the internet. Oh yes. Cast iron or aluminum intake?
I've been using ARP thread sealer for a while now. I used to use the old shellac types and Permatex Aviation sealer. The ARP product is by far less messier than anything else.
New Felpro head gaskets, bolts were clean but not oiled, I don't believe either the block or heads had been decked, and I'm using an Edelbrock aluminum intake and stock cast iron heads. Probably should have been more careful but like I said, I'm trying to fully recover from the nightmare of having had this stroke so I probably jumped too quickly; I'm really hoping to get out of this without pulling the motor and if I'm really lucky not pull a head. Pressurizing the system to exacerbate the problem makes a lot of sense to me. If I can see where it's leaking I can hopefully fix it. If it's just a weeping head bolt, I am again fortunate. If it's more, I've got an excuse to get some friends together. You go through something like this, you find out how blessed you really are- and how minor, in the overall sense, the things we worry about often really are. Thanks fellas-
if a head bolt is dripping outside, then others might be dripping inside (under the valve cover). be sure to drain some oil, see if there's water in the pan
Autozone or O'Reilly's usually have a cooling system pressure tester that you pay them for (deposit) and get a full refund when you take it back. They are and 80 something buck item so it works out well for those of us who only need one once in a while.
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