joshluther

iTrader: (24)

I just installed new heads on my motor and they're leaking coolant as soon as the pressure in the system comes up. The heads were cut just enough to clean them up but it looked alittle "coarse" is it possible to cut them to coarse? I used stock mls head gaskets. I torqued them to 22 Ftlbs and then 76* and then another 76*. Did I do something wrong?

Is there any way to fix this with out new bolt and gaskets?

vettenuts

iTrader: (4)

If the surface finish is poor on the head, they will be prone to leaks.

MSGHUFF

iTrader: (7)

How well did you prep the block surface? If its leaking and your sure on the torque then a new gasket is in order but def check the block and heads when its apart.

joshluther

iTrader: (24)

It's an iron block so I scraped it with a razor blade until it was spotless and washed it with some brake clean. I had a problem similar to this with a sbc and some copper head gaskets I used some wynns additive and it stopped should I try it again?

MSGHUFF

iTrader: (7)

I just re- read your post if you only did76 and 76 they arent torqed right it should have been 90 and 90 see instructions on www.LS1howto.com

joshluther

iTrader: (24)

Thanks MSGHUFF I'll have to try that first. I used the specs found in Will Hanzel's "Ls1 How to book" but I have found alot of misinformation in it.

Beast96Z

iTrader: (21)

What gasket did you use?

joshluther

iTrader: (24)

Stock MLS

GuitsBoy

iTrader: (4)

LS1howto generalizes by telling you to do 90 and the another 90. The factory torque angle specs were an odd number. It may have been 76. I feel that the issue is indeed with the roughness of the cut. Having recently milled down my own heads, you have to make sure all the inserts on the face mill are the same height. If they used "stepped" inserts, or if the level inserts were worn or beat up, youll get a rough surface. I took emory cloth and a sanding block to mine, followed by a stone to get a very flat surface. I also used the MLS gaskets.

sho-me speed

iTrader: (55)

Handzel's book says to torque to 22 lbs. then use an angle meter and turn76* and then another 76* with the short bolts only getting 34* the second time. It sounds as if your block surface is the cause of your problem not the bolt stretch.

triumphman

I would say if the deck surface of the head is rough that is probably your problem, mls gaskets require a smooth surface to seal.

Fireball

iTrader: (21)

from service manual:

Tighten the M11 cylinder head bolts a first pass in sequence to 30 Nm (22 ft. lbs.) .
Tighten the M11 cylinder head bolts a second pass in sequence to 90 degrees using the J36660.
Tighten the M11 cylinder head bolts (1,2,3,4,5,6,7,8) to 90 degrees and the M11 cylinder head bolts (9 and 10) to 50 degrees a final pass in sequence to using the J36660.

joshluther

iTrader: (24)

The block is a 2004 Iron 5.3 block the large bolts are all the same length so I tightened them all the same. I don't think there is anything wrong with the block surface it only has 15,000 on it.

I'm gonna try tightening them to 180* total. If that doesn't work I'll go with some Wynns it says it good for weeping cylinder head gaskets and it's worked before for me.

I should have checked the factory manual for torque specs and should have went with my gut and had the machine shop smooth them out some more...

slow trap

iTrader: (22)

is it leaking everywhere or just in the back or front.if it's not really bad some of those pills that bust up when you put them in might work,i forget what they are called.

joshluther

iTrader: (24)

It's leaking so slowly it's tough to say were it's coming from. Running it for a half hour it'll leave a spot the size of a dime. But it won't build any pressure in the radiator.

joshluther

iTrader: (24)

Tighting them to 180* total did the trick. Thanks guys I'm gonna go have a few for you guys now.

MSGHUFF

iTrader: (7)

Thanks for the feedback glad it worked!

SideStep

Good to know that it worked for you...