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Coolant leak from under heads help!!!!

7K views 21 replies 8 participants last post by  BogiesAnnex1 
#1 ·
I have a chevy 350 so I swapped the tbi heads for tpi 128 heads and 015. Head gasket and now coolant is getting the the cylinders and leaks between heads and block I torqued them 60ft pounds using the same head bolts did I do something wrong
 
#5 ·
Is your sbc a GEN I? If it is a an older GEN I sbc your heads will not work on this sbc. They will bolt up fine. The only way to tell for sure is to check your oil bro. Make sure the coolant is not in the oil. If it is not in the oil we are good, and just get some new bolts and bolt heads up specifically to BOLT SEQUENCE. I had a block I did not bolt in the order it is suppose to be bolted and had the same issue wih knew gaskets lol.

JD
 
#9 ·
Did you put some Copper-Cote on them? I had trouble with them leaking, then i used that. And thats on my 355 in my IMCA Stock Car, turning about 7200 rpm...never had a leak since i used some sort of sealer! Im not thinking its a bolt issue, check the torque on them, and if its still at 60, the bolts aren't to blame. I torque all my head bolts to 70 pounds, but thats with ARP studs.

Get a can of it, and use the WHOLE can on both sides of both gaskets, and i bet your problem goes away.
 
#15 ·
prettyboyced said:
I have a chevy 350 so I swapped the tbi heads for tpi 128 heads and 015. Head gasket and now coolant is getting the the cylinders and leaks between heads and block I torqued them 60ft pounds using the same head bolts did I do something wrong
If by 128 you mean the 14101128 aluminum head, they can't be sealed with a shim gasket. They require a thicker gasket that is either an MLS type or a composite. These will be thicker which will reduce compression. But the 128 head on a stock piston-ed bottom end may still have excessive compression problems, the chambers are a lot smaller than those of TBI heads.

Bogie
 
#18 ·
If that's the thickness you need for proper quench, you could use a Victor Reinz Nitroseal p/n 5746. The compressed thickness is 0.028", available from NAPA.

A couple from GM. I believe Bogie listed these in another thread:

GM p/n 10105117 multi-layered stainless steel gasket with a 4.1 opening, 0.028" thick, will handle some surface irregularities of the deck and head surfaces.

GM p/n 14096405- stainless over a graphite core, 0.028" thick.
 
#19 ·
prettyboyced said:
So I should get the gm .028 composite head gasket instead and yes them are the right heads
There's two .028 gaskets at GM. 10105117 has stainless steel faces on both sides and 14096405 with stainless steel on one side and graphite on the other.The 117 is intended for marine applications but can be used on the street. The 405 is a composite on one side, I like the composite as it provides some shear movement in the gasket to allow for the different thermal movements of the cast iron block and aluminum head. I've had good luck with either.

10185054 is the factory L98 and ZZ4 gasket which is what the factory puts between 128 heads and cast iron blocks, but at .051 thick it kills any compression gain and reduces squish/quench an awful lot driving you to higher octane fuel against the power output your getting or a reduction in timing and the loss of power that goes with that. Good gasket when warranty life is your highest priority.

On assembly you've got to really watch all the hole line ups. Modern economics have all the gasket manufacturers trying to stretch gaskets over more engines. So most come with pretty big bores and damn little material between the cylinders, so you've really got to eyeball these things to be sure you'll have a compression and water tight fit.

Aluminum heads require a hardened washer under the bolt head. Otherwise the act of torquing the bolts will cause the underside of the head to gall the aluminum under it resulting in high torque readings way before the bolt is properly stretched. This results in leaks. A lube must be placed under the washer and the bolt head to insure proper torque readings as well.

Bolt holes in the block must be clean and the same goes for the bolt's threads. The bolt holes in the block must be sealed even when using factory Teflon coated bolts otherwise coolant will work up the threads and leak out. I find about the best stuff that seals the threads and provides proper lubrication of them for proper torque readings is plain old Plumbers Teflon Pipe Joint Paste. But always be careful to insure that the holes you put any lubricant and compound into are open on the bottom because if the hole is closed and excess oil or compound gets trapped between the bolt end and hole bottom, it will bust the casting when you pull torque on the fastener.

Bogie
 
#22 ·
prettyboyced said:
So which headgasket should I get I have aluminum 128 58ccmilled down .010 and -18cc pistons 350 stock bore and block
My compression calculator pegs your set up with a .028 gasket at 9.496 to 1 SCR; with the .051 gasket that drops to 9.008 to 1.

Aluminum heads should be able to tolerate the higher ratio which makes the .028 gaskets look attractive.

I prefer the stainless on one side and graphite faced on the other 14096405 for auto engines and the stainless on both sides 10105117 for marine use. Reason being that auto engines are run hotter and go through many heating and cooling cycles so the graphite face allows the head to move around relative to the lesser movement of the iron block, so the sealing proprieties are longer lived. For marine while the load on the engine is usually continuously higher these engines tend to run cooler and aren't thermally cycled as often while generally requiring sealing that is more corrosion resistant than automotive applications. But I've used both on automotive and marine engines and they worked just fine, so I'm probably over-engineering the situation, a common problem of my personality.

There are three things you need to deal with when you put aluminum heads on cast iron blocks. They originate in the greater chemical reactivity of aluminum so some protection needs to be provided that an all cast iron sandwich isn't concerned about; and the problem of thermally caused differing rates of expansion and contraction between aluminum and iron.

The stainless steel faces or graphite or Teflon works the corrosion issues by putting a material between the aluminum and cast iron that doesn't allow the transfer of electrons from one material to the other.

The build up of a sandwich of gasket material allows movement within the gasket to absorb the differing rates of expansion/contraction between the aluminum and iron without breaking the surface seal with either part. This also reduces whats called "fretting" or "brinelling" which are terms used to describe surface erosion of the one part being rubbed in tiny amounts by another. The sandwhich also allows better conformibility with the surfaces it mates against which is more tolerance for un-flat or un-smooth surfaces.

Bogie
 
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