Still leaking?!!!!!!

[USMC302]

Correct me if I'm wrong...but why let it sit overnight with no coolant? The thread sealer needs to dry?

[~The Jester~]

That's the general idea. Not really dry, but setup good. The sealer should be non-hardening type, so it doesn't actually "dry".

[USMC302]

That's what I thought. Ok, I'm going to pull one bolt at a time, use the 555 stuff, torque to 95, and not fill it till the next day. Nothing is cracked, I've had it all double checked and the intake is mating up perfect, it's been on my setup before just not this block. I honestly cannot pull it all down and back together a 4th time, you will all be receiving post cards from the mental house. Unfortunately, the car is garaged in Tx so I'll be going home to try all of this after FFW (April 1-2) in Lousy-ana. 1st annual, we'll see how it is. Thank you all so much and I will def lt you all know. If anyone has anymore ideas please post.

[Hozer 88GTConv]

Oh shit!
You're supposed to let thread sealer set up?
Hmmm, that could be why I go through a quart of oil every 250 miles with no apparent leaks and no smoke....
When I last put my heads on, I waited about an hour before I fired it up
Sweet...

[USMC302]

Originally Posted by Hozer 88GTConv

Oh shit!
You're supposed to let thread sealer set up?
Hmmm, that could be why I go through a quart of oil every 250 miles with no apparent leaks and no smoke....
When I last put my heads on, I waited about an hour before I fired it up
Sweet...

Thread sealer would prevent water leaks, not oil.

Capri306, it only leaks when I fire it up, it does not need to be up to operating temp, pressure dependant is my answer. I was hoping it was the block because it was 100% gauranteed and decked, sonic tested, the full works. Houston Engine and Balancing in Houston did it and said it was all tested perfect. If the sealant doesn't work with the 95ft/lbs, then I will have the block tested again. They have a very high reputation and have never had a block come back. I wanted to say the heads because I didn't have this problem before I got them milled, but I got them tested.

[Capri306]

I'll throw in a vote for Permatex #2 non-hardening sealant. I have personally used that sealant since I was 15 and have NEVER had a leak when using it. Ever.

Having said that, if the threads aren't leaking and you're sure the heads are solid (flat and crack-free), that pretty much leaves the block to be the culprit. You can absolutely machine a deck surface or cylinder head too much! I have many possibilities of the source of the problem floating around my head right now, but I believe it's the machining that can make or break a seal.

Going back to the possibility of a bad block, I'm thinking that if the deck and/or the cylinder walls are machined too thin, the heat from the engine will cause thermal expansion of the relatively thin metal and start to push up on the cylinder head, causing a leak. Just a thought.

Does it ONLY leak when the engine it up to operating temperature and the coolant is under pressure? I'm wondering if it's temperature or pressure dependent, as that may eliminate a few possibilities.

[Capri306]

I'd say it's narrowed down to the block-head interface then iff the threads aren't leaking and both the block and heads are crack- and porosity-free. That's your only other option.

p.s. iff = if and only if.

I really hope you get this figured out, honestly. I can only imagine your frustration.

[USMC302]

Too much torque? The engine builder said I should be good up to 100ft/lbs.??

Since I am going to do this one bolt at a time with the "555", do you think I should just go with studs?

[Dark_5.0]

Since the heads have been on other cars with no problems I think you block is out of whack.

I torqued my aluminum heads down to 30 and then 50 and then 70 ft lbs.

I am using the same gaskets as you with ARP head bolts.

[USMC302]

I read in 5.0 magazine just the other night, the techs torqued AFR heads on a stock block to 95.......I think I should be safe. We'll see not this weekend but next, I'll post back up and let everyone know. Thanks for all of the input.

[andy669]

I'll believe what ARP tells me before any magazine article. 95ft.lbs should only be used if it is a 1/2 inch stud, which 351w's have.

Assuming the block was decked in the proper machine, its kinda hard to screw it up without noticing. Now if someone set it up in an endmill and took cuts with a 1" cutter, thats a different story. I really doubt its the block, or the heads. I think its just bad luck. Oh yeah, and the junk fel pro head gaskets. I always use Cortecos on my N/A stuff. They are excellent gaskets, and priced real reasonably. I buy complete engine gasket sets for $70.

Andy

[USMC302]

Originally Posted by andy669

I think its just bad luck. Oh yeah, and the junk fel pro head gaskets. I always use Cortecos on my N/A stuff. They are excellent gaskets, and priced real reasonably. I buy complete engine gasket sets for $70.

Andy

That's actually the best news yet, I know the heads are good and 99.999% sure the block is too. If the new sealant doesn't work I will try the Cortecos. I will try just about anything now.

[Dark_5.0]

Originally Posted by andy669

I'll believe what ARP tells me before any magazine article. 95ft.lbs should only be used if it is a 1/2 inch stud, which 351w's have.

Assuming the block was decked in the proper machine, its kinda hard to screw it up without noticing. Now if someone set it up in an endmill and took cuts with a 1" cutter, thats a different story. I really doubt its the block, or the heads. I think its just bad luck. Oh yeah, and the junk fel pro head gaskets. I always use Cortecos on my N/A stuff. They are excellent gaskets, and priced real reasonably. I buy complete engine gasket sets for $70.

Andy

The junk fepros have never let me down

[andy669]

One more thing I was thinking: Make sure theres not an extra head dowel pushed all the way up inside the head. Some times reused dowels can be real loose and when you pull the head off you might not even see it cause its all the way to the top of its bore. If the machine shop put new ones in, and theres one still stuck in the head, that will definately cause a leak. A similiar situation happened to me a few weeks ago, but it wasnt on the motor, it was on the flow bench. For awhile there I had the best flowing intake port in the country (it was sucking air beneath the head surface). I didnt notice what the problem was until I reversed the bench to exhaust and the rubber seal between the head and plate started flapping.

Andy

[~The Jester~]

Good call! Never thought of that!

[Rev]

Originally Posted by andy669

One more thing I was thinking: Make sure theres not an extra head dowel pushed all the way up inside the head. Some times reused dowels can be real loose and when you pull the head off you might not even see it cause its all the way to the top of its bore. If the machine shop put new ones in, and theres one still stuck in the head, that will definately cause a leak. A similiar situation happened to me a few weeks ago, but it wasnt on the motor, it was on the flow bench. For awhile there I had the best flowing intake port in the country (it was sucking air beneath the head surface). I didnt notice what the problem was until I reversed the bench to exhaust and the rubber seal between the head and plate started flapping.

Andy

That actually did happen with me recently. I was reinstalling the heads temporarily to check piston/valve clearance after a new cam installation. I only installed the passenger side head with the old gasket to check the clearance. I noticed that I was missing a dowel which I knew I had earlier. You guessed it, there was an extra one crammed in the hole at the rear of the passenger side head. I'm damned glad I found out before the final installation of the heads after all the work of a new cam and intake being installed. Fortunately, I caught that screw up before it could do any real harm.

Rev

[Ieatcamaros]

Nice new avatar, Jester.

I hadn't thought of the head dowel either. Good call Andy. I'll also agree that 95 ft/lbs. is too much on a 7/16 bolt. When you take the heads back off, check your bolts. I know you said they felt good when you torqued them down, but they could still be ruined. I'd take the threaded ends of each bolt and mesh the threads together with another bolt to see how they look. I hope that makes sense. One more thing, is it leaking in the same place every time?

[USMC302]

Dark5.0, thanks for that and also the performance shop I talked to said yes ARP says one thing but he has never had a problem with too much torque on those bolts up to 100, I decided I'm going studs just to be on the safe side though. Like you, I have never had to torque aluminum heads down passed 70ft/lbs for a good seal.

Andy669, yes I checked that, I was wishing it was only that easy. Also checked to make sure the dowels seated all the way once in the heads, it's not stopping the head from seating at all.

Studs, 555, 95ft/lbs and let is sit over night before filling it up is what I'm going to try. But as mentioned before it seems pressure dependant and I was also told these were the symptoms of a crack (leak when heated). If this doesn't work, then I think it won't leak if it's at the bottom of the river.

[HotRoddin]

It may not be exactally what Andy said, but my bet would be something similar to that, like a puckered headbolt hole or something. Perhaps incompatable gasket / head / block combo ?

If it can't hold coolant just starting it up and idling in the driveway then it has to be something obvious ... a large crack or a serious warp or low/high spot on the block / head.

I'm curious about the leaking headbolts theory, even if you have coolant coming up past the bolt threads, that area is still sealed from the outside world by the head gasket ??

Anywho, like everybody else, I'm curious to see what ends up fixing this one, please let us know, and good luck

[~The Jester~]

Originally Posted by HotRoddin

I'm curious about the leaking headbolts theory, even if you have coolant coming up past the bolt threads, that area is still sealed from the outside world by the head gasket ??

Sort of. Look at your head gaskets next time you have them off. Not a lot of effort is put into sealing of those bolt holes. Well, not nearly as much effort as sealing of the combustion chamber for sure!

The spray stuff (at least around here) is called Copper Head, and it's made especially for head gaskets. AZ/Advance should have it.

I was SOOOO frustrated at Fun Ford last year. Thrased to get the car done (left mine at home AGAIN) drove up there on 2 hours sleep, set valve lash, changed oil etc etc. Get ready for 1st round quals, and then the leak started. I was Smokin Mad! The head studs are what killed us. Leaked right up through the threads, and to the "outside" world anywhere it could, including the oil pan. We actually saw it ooozing up through the nut (think studs now) is the only way we found it. Had those been bolts, we might not have found it that easy.

Guess I'm trying to take one of my bigger boo-boo's and help make it "all better" by making sure USMC isn't having the same problem. I'm not saying it IS his problem, but I sure as hell hope it's something that easy.