Cylinder Head Retorque

[Joao46]

Hi. I have a 1931 Chrysler Imperial that the previous owner had recently replaced a head gasket , which for that engine (6.2 liter inline flathead) I would assume is a copper gasket.

 

After running it for a bit I noticed a slight leak of coolant from a spot in the rear of the engine. I retorqued the head and it was clear it needed it as most of the nuts turned a little. 
 

Leak went away, then I drove the car about 30 miles and ran the engine a few times in the garage as I tuned it.

 

Then as I revved the engine, checking the timing , I saw a small puff of smoke coming from one rear head nut. 
 

I again retorqued the head, noticed a little bit of movement on most nuts (much less than before) and the puff of smoke went away.

 

I’m assuming these little leaks I noticed were signs I needed to retorque the head, since it was recently replaced. 
 

Im just sharing this to get some of the experts here opinions. Do you agree these issues were just signs I needed to retorque the head? 
 
Or is there something more serious going on?

[Mark Gregush]

Did they use any copper coat sealant that you can see looking at the seam? I retorque heads several times after going through several hot/cold cycles. 

[Grimy]

Reproduction sandwich-style head gaskets with plastic rather than asbestos centers require at least five re-torques, in my experience, before all the potential "squish" is taken up.  When available, I'm happy to pay the extra money for NOS asbestos-center gaskets which generally only require one or perhaps two re-torques.

[c49er]

It will soon stop showing tiny signs of leaking on your 385ci. aluminum head Imperial engine after your re-torque's.

[EmTee]

I'd continue to check the cold torque as needed until it no longer requires tightening.

[DFeeney]

If you have the head off in the future be sure to check for flatness.   As many heat cycles as these old engines have don't be surprised if it out of spec.

[Gunsmoke]

curious what ft/lbs you are torqueing the head bolts. On my '31 Chrysler CD8 (240CI) I was advised to be cautious of over-torqueing after I did the valves and installed a new gasket (old style, copper asbestos). Gradually re-torqued in a set of stages, 50, 60, 70 lbs etc using sequence pattern recommended. I think my studs were 7/16". No leaks after a couple of warmups, but engine has not been run for more than a few minutes. I plan to re-torque after next run, but was advised to be careful about going above 75 ft/lbs, not sure what recommendation is for your engine. 

[keiser31]

1 hour ago, Gunsmoke said:

curious what ft/lbs you are torqueing the head bolts. On my '31 Chrysler CD8 (240CI) I was advised to be cautious of over-torqueing after I did the valves and installed a new gasket (old style, copper asbestos). Gradually re-torqued in a set of stages, 50, 60, 70 lbs etc using sequence pattern recommended. I think my studs were 7/16". No leaks after a couple of warmups, but engine has not been run for more than a few minutes. I plan to re-torque after next run, but was advised to be careful about going above 75 ft/lbs, not sure what recommendation is for your engine. 

I go by this most times....

[Joao46]

My head is iron and I was advised by a mechanic familiar with the car to tighten to 55 ft lb

[Grimy]

I agree with 55.  As the owner of three Pierce-Arrow 8s, I'm aghast at the 83 specified in Keiser's chart for those engines.  I torque my iron heads to 55-58 max.

[Joao46]

Speaking of torque, what about the wheels? My car has 7 lug bolts. Would 100 ft lb be too much?

[JFranklin]

My average wheel torque usually is 70 Ft#.

[John Watkinson]

Could Kaiser31 enlarge the torque settings for cylinder heads - Chrysler to Studebaker

Thanks

[keiser31]

31 minutes ago, John Watkinson said:

Could Kaiser31 enlarge the torque settings for cylinder heads - Chrysler to Studebaker

Thanks

I am having a problem with enlarging capabilities these days.

[JFranklin]

34 minutes ago, John Watkinson said:

Could Kaiser31 enlarge the torque settings for cylinder heads - Chrysler to Studebaker

Thanks

Have you tried enlarging it on your computer? I am able to read it on mine.

[John Watkinson]

Yes , I’ve enlarged the document but lost definition - I don’t want to guess the numbers . 

On 12/26/2023 at 4:14 PM, keiser31 said:

I go by this most times....

 

[keiser31]

5 hours ago, John Watkinson said:

Could Kaiser31 enlarge the torque settings for cylinder heads - Chrysler to Studebaker

Thanks

I can send it to you in a private message and maybe you can work with it.