Still leaking?!!!!!!

[USMC302]

Here's the short..... 88 stang new EFI 331, block tested and decked, TW aluminum heads. First build, it leaked water from both head gaskets external and internal, followed torque sequence and yes the right gaskets were used.Torqued to 75lbs. It didn't blow, just leaked....Called Trickflow, they recommended torque to 80lbs. I got the heads tested because Trickflow said they had to be within 3/1000 of a perfect mill. They were perfect.
Pulled it all apart, put on new gaskets, torqued to 80lbs, leaked again.
Pulled it all apart, got new gaskets again, bought a new torque wrench, thinking it was not getting the right specs torqued down to 80lbs.....leaked again. Called speed shop and they said they torque their aluminum heads down to 95lbs and to go ahead and tighten them to 90lbs as it sits. THIS stopped the internal leak, so with no water in the oil we drove it around the block. Drives great, sounds great, runs great. STILL LEAKS external only now and only on the driver side.
So now $300 in gaskets later and tons of sweat and blood, I'm going to do this for a 4th time and torque to 95lbs.....

Comments?! Experience this problem before? I've done 9 or 10 motors with no problems, this is the first....

[Gs835.8Stang]

My only thoughts are (and you have probably already thought of these or tried these), are you sure the block/heads are not cracked? It seems like perhaps the heads were not cast correctly. As long as you are sure the deck on the block is square (and was done properly, I have seen blocks that were not properly decked cause numerous problems, when I refer to being done properly, I not only mean a square surface, but also in keeping the correct angle with the line bore of the block), the only other obvious thing I can offer is are you putting any sealant on the head bolts that go into the water jackets? That will case an immediate leak for sure. I believe there are a few on the Windsors that do go into a water jacket. I hope this helps. Good luck, let me know what the problem is/was when you get it figured out.

[USMC302]

Heads are perfect, and I had them milled and tested twice. I was thinking that too after the 2nd time.. They have been on two of my other cars so it's not the casting. Sealant was also used. ARP thread sealer.

[~The Jester~]

The bottom head studs are leaking up through the threads. GAAA-RUN-TEE. Studs are only supposed to be "hand tight" in the block, but ya gotta use GOOD sealer on the threads. Had the same damn thing happen to me when we thrased all night to get ready for Fun Ford last year. Worked on the car until 6:00 AM, got 1 hour sleep, drove for 2, unloaded the car, and you guessed it. So we drank all weekend instead.

Anyways, got off topic there. I'll bet ya a donut that's your problem!

[USMC302]

But I'm not using studs... I've got the ARP bolts and I used the sealant....??

[~The Jester~]

What kind of sealer? A friend of mine (has one of them bowtie thingys) could only get is to quit leaking using silicone. I've always had good luck with "555" with Teflon. Comes in a can with the brush in the lid, available at Home Depot or a local hardware store.

If you're SURE the block and heads are OK, that's gotta be it dude. If it was a bad (new) gasket, changing them would have fixed it. Odds of getting 2 "bad" gaskets in a row are about 3 bajillion:1. Tightening the head bolts to eventually get it to quit leaking internally tells me it's not a crack. Cracks will leak ALL the time.

That's a tough one man. I'd yank out the bottom bolts (Toward the exhaust side) one at a time, and try a different sealer and go from there. I feel your pain bro!

[USMC302]

Originally Posted by USMC302

ARP thread sealer.

I will definately go get the "555", but I was always told not to use teflon tape, it would throw off the torque readings...I sure hope your right about it being a bolt leaking, I've already spent $300 in head gaskets.

[USMC302]

Would this also be causing problem #2? When it's hot, it will turn over and over and over and not start, after about 1 hour, she starts right up. New coil, new ignition, new Dist, hell new everything. My Fuel pressure reads around 32psi running but smells hella rich outside, could it be flooding it out?

[~The Jester~]

NO TAPE! The 555 is a paste. If you can't find the 555, I think it's called Uni-lyte or something similar to that. It's actually used for sealing threads on black iron natural gas lines. And yes, it will throw off your torque specs. But look at it this way. Right now your torque specs are dead-ballz on..........along with leaks. If they say to torque to 85 ft/lbs (By the way, what's with all the car shows saying "Pound Feet" of torque now? When did "they" change it, and just for the record I'm not switching. It's "Foot Pounds" ) I add a few just for that reason. If they say 85, use the 555 and torque to 87-90. Not saying the 555 WILL fix your problem, like I said my buddy tried everything under the sun, and the only thing he found to work was high-temp silly putty. I shudder at the thought, but ya gotta do what ya gotta do.

If the head bolts are leaking coolant into the cylinders, even minute amounts it'll have trouble starting when hot (cuz the cooling system is pressurized) once it cools off (no pressure cuz of the leak) it'll fire right up. I've heard of crazier things happening!

Try the 555 first, then other options are Indian head, Permatex makes a non-hardening sealer in a tube, and then there's the high temp ultra grey as a last resort. The other thing I'd do is drain the coolant, torque down the bolts with the new sealer, then let is sit for an hour or so. Let that stuff set up, THEN refill the cooling system.

Keep me posted on this one bro.

[Ieatcamaros]

Have you always been filling her up with water/anitfreeze when you get done? After reading all this I was gonna suggest what Jester said in the end of his previous post. I make it a usual practice to let any motor set overnight without any water in it after taking the heads off. Of course, I don't do this for a living either. I think that doing this alone is worth a try if you haven't already. As frustrated as this sounds, I'd probably get that 555 stuff Jester is talking about and let it set overnight before adding any more water to it. Just my $.02. Hope you get to the bottom of this one.

Oh yeah, I don't know what's with this "pound feet" crap. It annoys me to hear it like that. I agree it is still FOOT POUNDS! LOL.

[HotRoddin]

If you were leaking at 75 ft lbs under light load (idling or just easy driving), then you have problems other than the correct torque on your head bolts.

What is your engine, head, gasket combo ?? Can you tell what area it's leaking from ?

Somethin ain't lining up !

[~The Jester~]

Went out to the shop last night, it's called "555 Select-Unyte"

[Gearhead999]

Is it leaking external from where?? Is the intake mating up OK??
Has the block been decked?? Mayber too much??

Are any of the headbolts holes showing signs of "puckering up" around the edge of the threaded holes in the block?? Need to be relieved there. Are any of the headbolts "mushy" when you torque them?? Not holding the torque good.

If everything is flat, the headbolts are good, the treads are sealed, the intake meets the heads correctly and the gaskets are correct....well something has to be cracked.

Wish you were closer. Hey, you'd be warmer !!!! I had a 289 in my shop doing similar antics. Fill up crankcase and fill up intake manifold with water. Cylinder heads were machined too much and they wouldn't seal. Have seen Ch**Y's do that, but they had angle cut heads to up compression ratio, too much too.

I'm interested to hear what fixes it, besides a stick of TNT.

[rwhite65]

I like the idea of letting it sit over night before filling up the coolant system. I also wonder if the head bolts aren't getting stretched by this point. I am seriously interested in hearing the fix for this.
keep us posted!
Ryan

[USMC302]

Originally Posted by HotRoddin

If you were leaking at 75 ft lbs under light load (idling or just easy driving), then you have problems other than the correct torque on your head bolts.

What is your engine, head, gasket combo ?? Can you tell what area it's leaking from ?

Somethin ain't lining up !

331, decked, with the TW aluminum heads non-o-ringed, with the felpro 1011-2 (copper ring)

the leak is coming specifically from between the head and block, where the mate, between the 4th and 5th bolt locations. Yes, block has been decked, I didn't know you could do it too much... I had it done by a reputible place. Bolts actually feel good, there new ARP bolts, maybe I should go studs...?

[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...

[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.