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Discussion Starter #1
coolant from the outside studs,
do I retorque the headstuds and hope for the best or do a full
head gasket swap.This happened last Sunday and the car has not been run since, headers are already of to get a better view.
 

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The Smell of Nitro in the morn
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After draining coolant.
Take each one out starting with #1 bolt/stud , any bolt that goes into the water jacket MUST be sealed.
I use what Dart recommends, Permatex #2 that stays soft.
A little goes a long way. Then re-torque the one just finished and go thru all of them if you want to stop future leaks.
 

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Discussion Starter #4
When I assembled the engine I used Fel Pro "Pli-A-Seal" on all the studs, which is a #2 type non hardening gasket sealer.
I did´nt notice any lack of coolant, and I check it regularly.
The day it sprung the leaks I had been in slow traffic for half an hour, the engine was running at 210º F quite happily.
 

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Discussion Starter #6
I got a reconditioned 350 short block bored 0.040 over, the heads are World Poducts S/R 305 Torquer and the head gaskets are Fel Pro 1003, 0.041 thick. I torqued them in steps to 65 lbsft.
as per "how to build the smallblock Chevrolet"
I got one valve cover off and don´t see any coolant lying about
under the rockers, it appears only the outside short studs have leaked. The pistons are 0.040 down in the bore and my compression worked out to 10.1 : 1. I don´t know if the block was decked, the heads have not been touched, they spent a year on my old 305.
The engine was assembled in May 2003 and has given satisfaction up ´till now.
 

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Discussion Starter #7
To be sure I´m taking the heads off, the drivers side is off.
Here is a picture of the rearmost cylinders, anyone care to comment on the state of these?
 

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malc said:
coolant from the outside studs,
do I retorque the headstuds and hope for the best or do a full
head gasket swap.This happened last Sunday and the car has not been run since, headers are already of to get a better view.
is it possible that you have a cracked outside stud water gallery?
 

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Discussion Starter #9
Nothing cracked, just just coolant had leaked up the head studs
due to "breakdown of sealer" or "I applied too little".
The motor is nearly back together, I had the heads off yesterday
and cleaned and back on today, at last light I tightened down
the intake manifold.
 

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malc said:
Nothing cracked, just just coolant had leaked up the head studs
due to "breakdown of sealer" or "I applied too little".
The motor is nearly back together, I had the heads off yesterday
and cleaned and back on today, at last light I tightened down
the intake manifold.
slap that sealer on,, good to see it was an easy fix..

Simo up late from aus..
 

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machine shop tom said:
A little info, please. Were the heads or block decked? What kind of gaskets were used and what were the fasteners torqued to?

tom
I was wondering that too; are the cylinder head and block surfaces straight (within spec)?
 

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NYOFP4RJ3CHRIS
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malc said:
I torqued them in steps to 65 lbsft.
as per "how to build the smallblock Chevrolet"
I noticed you have studs for fasteners. It's been my experience that studs generally have a finer thread pitch than bolts and therefore require less torque to achieve the same clamping force. You might want to refer to the stud manufacturers torque specs.
 

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BstMech said:
I noticed you have studs for fasteners. It's been my experience that studs generally have a finer thread pitch than bolts and therefore require less torque to achieve the same clamping force. You might want to refer to the stud manufacturers torque specs.
Very good point, but something I have had trouble with. ARP usually recommends over the factory sped. But, with the added clamping of a stud, it seems to me like block distortion could be a big problem.

Chris
 

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Discussion Starter #15
It´s all back together (Sunday) and it started first time.
Took it out for a shake down run about sixty miles, seems to be perfect.
I torqued the heads leaving quite a time between stages and went round as per the book.If the clamping force is applied evenly and all studs or bolts are the same torque, why should there be distortion?
 

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NYOFP4RJ3CHRIS
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malc said:
I torqued the heads leaving quite a time between stages and went round as per the book.If the clamping force is applied evenly and all studs or bolts are the same torque, why should there be distortion?

Over torquing can be as bad as under torquing, or an improper sequence.

I'll bet you just had a problem with the sealant, just thought I'd throw my two cents in though. Glad to see you back on the road. :cool:
 

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malc said:
It´s all back together (Sunday) and it started first time.
Took it out for a shake down run about sixty miles, seems to be perfect.
I torqued the heads leaving quite a time between stages and went round as per the book.If the clamping force is applied evenly and all studs or bolts are the same torque, why should there be distortion?
Distortion is normal. Any time you torque a head, the block distorts some. That is why torque plates while honing yeild a straight bore when the head is torqued on. Without, there is some out of round.

Chris
 

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All you really have to do is run some radiator stop leak. From what I hear this is standard from the factory on a new car when a fresh engine is installed. You really dont need to take the thing apart.
 

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Discussion Starter #19 (Edited)
When I first did this, I was reading in one of the car mags an article on using head stud fasteners, they reported when installing a stud into the head, finger tight is the proper method.
Going back in there showed me finger tight is rubbish, although the threads were very clean, used tap and brushes, finger tight can vary. So I reckon some of the studs had lost their clamping force. This time I did the finger tight and then snugged them up
just enough to make them bite.
Due to confusions in conversions from lbsft to Nms I may have overdone it the first time.
As for any problems with block or head out of true I´m stuck,
I have not heard of or seen any machine shop set up to do this type of work.
I used a Fel-Pro head gasket 1003 before now I have
Fel-Pro 1044, a tad thicker so I´ve lost some compression.
BTW by the state of some of the studs ie no sealer it would take a lot of rad sealer to cure it.
Checking out torque values, for ARP-134-4001 655 lbsft is okay.
 

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malc said:
As for any problems with block or head out of true I´m stuck,
I have not heard of or seen any machine shop set up to do this type of work.
I
The distortion is in the cylinder walls not the head or deck surface. Just wanted to make sure you understood that. It only effects ring seating, not sealing. We got off on a tangent a little bit.

Chris
 
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