Water Leak from Head Stud
 

Just got my rebuilt engine running and I pulled the valve covers off to check lash and noticed water oil milk shake around the drivers upper rear head stud. (First pic) I torqued the heads again and drove probably 20 miles and just checked after sitting for two weeks and came across this.(2nd pic) These are pre 2002 e heads. New felpro 1016 gaskets. Could my head bolt hole actually go into the water jacket? https://uploads.tapatalk-cdn.com/202...4845a02645.jpg
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When we dynoed my current motor in my 78 over 2 days there was so much condensation overnight it slightly milkshaked the oil in the valve covers when we went to swap rockers.

On a factory block all the head bolt holes are blind.

If I recall right on the first production IA blocks the lower front pass side head bolt hole is open into the water jacket.

It's common for the first design heads to crack and leak water there. It could also be leaking from the head bolt boss if there is a crack going into the water jacket. Sometimes when installing a head bolt heli-coil the drill can break into the water jacket .

Its a factory 1973 block. I had these heads on the previous block and didnt have this problem. It’s definitely not condensation as it is only in the drivers side and that my second pic shows that its literally straight water, like the oil separated up and out the drain. All that is new is the head gaskets and a different 1973 decked block.

Maybe someone ran that stud down too hard, causing a crack into the jacket. Seal the threads on that stud using commercially available sealer. Solved!

I think this is spot on. Crack in head bolt boss.

Yes, the early E-heads had issues in that area. We ended up sleeving those two inner holes and the center outside hole with thin wall SS tubing glued in. Then I machined the top of the 10 bolt holes for step washers. That took care of it. It is a fair amount of work. You have some easier options to try first. I would put a radiator pressure tester on the system with the valve cover off and try to verify the exact leak point. If it's just that one stud, remove it as mentioned, and put some sealer on it and re-torque. I like Permatex aviation form a gasket for this job. Sticky liquid non-hardening sealer. If you don't like that, pipe sealant with teflon is a decent alternative. If you PM me, I can send you a couple cartridges of a miracle sealer you put in the radiator. It is not commercially available, only to radiator shops. It is an amazing sealer. Finally, I would reduce your radiator cap to a 7 PSI cap if your car doesn't run over 210. That will take a little of that failure point.

I know I have tubes in between the intake ports, but I am not positive about the others. Thanks guys ill report back after testing.

Thanks.... Congratulations on your new build. That thing is going to make some steam!

Thank you Paul!!

I'm super happy with the results. Brad did a great job on it for me.

Agree.... Please keep us posted as you dial it in.

If all goes well I plan to be out testing spring of 2024.

Jeff

is there a date code or part number to detect the older heads?
was it just an e-head issue or other aluminum heads?

Not sure about date codes or casting numbers. But they are visually different from the outside. We had some of the very earliest castings from Edelbrock for use in the Grocery Getter drag car. After a few removals and installs, the problem began to show up. We had a direct contact with Rick Roberts, chief engineer, and reported issues to him. They of course had others with similar experiences and made a decision to revise the casting for the next run. The improved castings had the column under the head bolts enlarged and the end stud location under the valve cover was left taller, on the same plane as the center stud location and not down in a deep counterbore. The revised head takes different studs, longer ones. That seemed to take care of the majority of the cracking issues on the ends. Taking the time to install step washers is a good idea in E-heads that will be coming on and off frequently. The last version of the heads received the heart shaped chamber and the thicker columns under the head studs. I doubt any further development will happen with the Edelbrock Pontiac head as Rick Roberts, PHD was fired before the ink dried on the paperwork when the Industrial Opportunity Partners bought the company. It's all about fast moving shiny parts now. Niche markets don't typically produce large profits.

If I did have a crack in the head, is it most likely in the top of the head near the counter bore? Is there any repairing that can be done or am I screwed?

The change date was 3/15/02 ..... Mike covered how to ID the different heads.

If you picture taking a socket attached to an impact wrench and going to remove the rear head bolt under the valve cover, now pull the impact towards the front of the car, where the socket contacts the head is the area the head may crack. IDK how else to explain it. I hope that makes sense.

It's in that general area. Again, I would like to see you put a radiator pressure tester on it before removing the stud or the head. Just as it sits now. You should be able to see the source of the leak. If not, then I would just seal the stud in the block and re-test. It is always possible the water is wicking up the stud from a tiny crack on the block stud hole. We may be assuming it's the head because Edelbrock did have some issues with them in that area. "A test is worth 1000 expert opinions". Hope you find it.

I always thought the redo was just so there were not so many different length head bolts like the early ones. I've got early on my 78 as well as the IA motor and "knock on wood" no leaks! And my first set KRE tubed the crap out of them pushrod tubes and head bolt holes in the common wall. Kind of a shock when I got them back!

Its definitely leaking from that stud. I rented the tester from AutoZone and checked it as is. Water started to seep from that stud. I removed the stud and checked it. Used my fancy amazon bore scope to look down in hole. Looks like its coming from either the bottom of the head itself or head gasket. But it's hard to say whether or not it was leaking there because there was no clamp from the stud on it.

Was the stud perhaps bottomed out in the hole when the head was last bolted down?
If so then the clamping loads may have simply been less then what was needed to seal the head gasket.

At any rate even though is a PIA I would pull that head off to fully check everything.

Get the hole clean and dry. Put pressure on it again and see where the leak comes from. If it's coming from the head bolt hole I would drain the cooling system. Get everything clean and dry again and put some type of sealer on the stud threads. Install it and torque. Let that sit up and refill. You should be fine like that. Chevrolet head bolts went into the coolant for many years.

The problem with going that route is this.

If there is a crack at the bottom of that head bolt hole there is then a really good chance that it will continue to spread and in time then really screw you!

If I found / pinned down a crack in the bottom of a head bolt hole in my motor then I would simply drill out the bottom into the jacket, totally clean and dry it out and then use sealer just like the SBC guys use.
At least then you stand a chance of eliminating the crack and you can then sleep at night and go on your merry way.

If there’s is found a crack running UP the wall of that head bolt hole then the needed torque to clamp the gasket down on that corner will never be achieved ( at least by means of a bolt) and unfortunately the block is done!

In thinking about this a bit more, if a crack is found in the wall then the use of red Loctite would be my pick over sealer, as that might buy you some run time.

With the engine in the car, your options are a little limited. I don't see a big down side to trying to seal this stud, especially in a race car. If you want to use Locktite product, I would seek out Locktite, high solids hydraulic sealer. Regular high strength like 271 or medium strength 242, likely will not seal a crack, not designed for that. They are too thin and can't seal out the air to cure. Locktite 545 might be worth a try. I like Permatex aviation Form a Gasket liquid for this application. I would not bottom the stud, let it float in the block. Snug then back out 1/4 turn. Torque it in place, re-pressure test. Not much to lose. Just keep an eye on it.

What is the theory behind turning the studs back the 1/4 turn? I have heard that many places but ARPs instructions say " it is extremely important to ensure that the studs are fully bottomed out in the hole in the block and not hung up on damaged or corroded threads in the block preventing the stud from being fully seated."

My $.02, Never had any luck with Felpro 1016, never had a problem with Cometic

The problem is essentially where the stress is applied to the block structure, especially an iron block. If the studs were the perfect length and the threads ended exactly at the top of the block deck surface, I would be OK with that statement. In a blind hole, like a Pontiac, if the stud bottoms out before the threads are used up on the bottom of the stud, burying the stud in the hole is how the block becomes cracked. In a SBC, where all the bolt holes pass through the deck and all are wet, this is not an issue. However, I still do not like the larger diameter of the stud above the threads bearing down on the brittle deck surface where it can create a stress riser and crack the deck. Aluminum blocks are different. They generally take studs with a bullet nose end on the stud that is supposed to be buried into the soft aluminum material at the bottom of the bolt holes. There is often a torque spec. given just for the stud like 20 ft. lbs. I would take issue with ARP saying not to let the stud get hung up on bad threads. IMO, the stud should not be installed in a hole with bad threads until that situation is resolved with clean chased threads or a repair insert. I think they are more or less saying just make sure they are fully installed. I have learned allot from ARP and will try to get some clarification.

I have seen many small block 400 Chevy engines cracked from the head bolt hole to the cylinder and the owners say yeah it's been like that a while. Run it till it becomes a issue.

Water Leak from Head Stud
 

https://youtu.be/FoUxFemTR28?si=b-pIj8xxeu6IPFgI

Its looking like the worse case scenario. I cleaned hole and re-pressurized. In the video you can see me blow off the 3 water droplets on the counterbore. Shortly after the 3 droplets reappeared. Mike do you think those coolant tablets will help me?

That's a bummer!

What if I made an aluminum spacer that was about 3/8" tall, that fit well in the counter bore fully seated flat. Then I use some good epoxy on the bottom and the sides?

Long before Cometic came to be I have run the 1016 with 8 psi of boost and just head bolts and never had a problem, things just need to be done properly mechanical,y and no detonation please at least under boost pressure.

Haven’t seen anyone mention it and I assume you already checked but thought I would mention it to be sure.
Did you check the head stud length? With parts quality control these days things happen. Or if the head was decked more.
Make sure when you’re torquing it the nut is not bottoming on the threads before it’s fully tight. We have had some that after decking the heads a lot the stud was a few thousands too long. We added another head stud washer to get the proper torque.

But there are plenty of types of motors that have studs that go through to water jackets. On those type motors they put silicone in the head studs and seal them up. I think it would seal with silicone no issues.

Haven’t seen anyone mention it and I assume you already checked but thought I would mention it to be sure.
Did you check the head stud length? With parts quality control these days things happen. Or if the head was decked more.
Make sure when you’re torquing it the nut is not bottoming on the threads before it’s fully tight. We have had some that after decking the heads a lot the stud was a few thousands too long. We added another head stud washer to get the proper torque.

But there are plenty of types of motors that have studs that go through to water jackets. On those type motors they put silicone in the head studs and seal them up. I think it would seal with silicone no issues.

Its definitely not the threads in block leaking. The old version eheads are weeping water from the counterbore. I dont think ill use epoxy for the spacer plug im going to make, I'm now leaning more toward using the permatex aviation sealer or maybe RTV.

I have sealed up leakage with gasoila products in situations like yours.

The motor in my 57-wagon is leaking in the same place.
It's leaking in the hole of the head where the stud go's.
I left the intake and valley cover off and the oil pan to find
the leak. I filled through the thermestat hole then I seen the
leak and it was coming from the hole in the head for the stud.
I think I'm gona try and sleeve that hole with brass tubing and
JB-Weld the ends I'll silicone the sleeve before installing (RTV)
I think I'll also RTV the top under the washer too. I'll let ya all know

GT

Great video. You can see the water weeping around the crack in the OD of the counterbore. That's the regular crack area. I think machining the counterbore for a step washer and JB welding the step washer in place will fix it. The right way to do this is pull both heads, set them up in a mill and cut all 20 holes for step washers. Now that that is out of the way you can fix this single one on the car if you have room to get a cordless drill in there. I have step washers, 1/2" size I think. Have to look tomorrow. I also am not sure if I have the counterbore tool. I have all the stuff for the big 9/16" studs we used for sure. Just not sure about 1/2". If I have the tools and if you have room for a cordless drill, you can drill for a step washer with a hand drill, glue it in and your back in business. PM me and I will check in the shop tomorrow.

Also have to be careful, with blind holes, not to have water or oil in the bottom of the hole. Always clean them out thoroughly before installing bolts or studs. You can hydraulic the hole and break the block. I like to tighten them down slowly and in steps.

I just whipped these up. I have made the diameter a few thousands different on each to pinpoint the best fit in the hole. I probably will end up redoing all of the flanges with the inserts one day. But I still haven’t broke the motor in fully and I want to get that done soon. Any recommendations on sealant for these?


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I see what you have done there and it looks like a good try. As far as fit in the counterbore, I would make sure it has plenty of clearance on the ID, not even snug on the stud. Then just a zero slip fit on the OD wall in the counterbore. My thinking is if there is a press fit on the OD, that might open up the crack as it heats up. As far as sealer, I would try epoxy or JB weld. You want the sealer to be somewhat flexible and JB does a good job with that. Once dry and ready to assemble, use plenty of ARP lube on the stud, the nut flange and the top of the washer only. You want the nut to slip on the washer and not tear your aluminum spacer away from the head when torquing in place. Do you have a longer stud your going to need for this repair? I have some 1/2" ARP studs but will need to know the length you need. I can send it along with the sealing powder if you wish. Good luck with it. I would give this repair a 75-80% chance of working. Not bad odds. Good luck with it.

Thanks Mike, I have some studs from the old set that I believe I can make work. Ill try this fix out before going to the 'magic dust'. Would you suggest when I set the spacer with epoxy in the hole that I install the stud and do a finger tight torque while it sets? I was thinking a light torque like 20 ft/lbs just to make sure its seated.

That sounds like a good idea. Bars leak powder or GM cooling system tabs should go in the radiator as well. Not as good as the stuff I have but for any weepers that are left, it works. Every new GM car sold has some in the radiator.

Just wanted to update and say that my head is no longer leaking! I first installed the spacer with aviation form a gasket slathered around. Then I added the Ac Delco Cooling system tabs crushed up into the radiator. I was skeptical of the tablets at first but my research is showing that new cars employ sealers like this as standard procedure. It really is some magic stuff. Thanks for the suggestion Mike

Good news to hear!

That is good news. That powdered sealer saved our butts many times at the drag races. When you have a match race to run and people expect you to race, you can't let a little water leak stop you. We learned all kinds of little tricks from Arnie Beswick. He was the master of getting sometimes marginal equipment down the track and running the very best it could.