retorquing heads,where do i start?

hombres ruin

hombres ruin

Well-known member
hi guys i am about to retorque the offy aluminum heads on my 50 8BA.The reason for this is to trouble shoot a problem i encountered that may need a retorque to fix.question is what torque would you start at for the aluminum heads,45 ft lbs? or something less? .thanks for the help.
 
Thanks 19fordy,very helpful,interesting to note that one torque spec for 1949 to 1953 has a different sequence then the one for the manual dated 1948.
 
When torquing a gead start in the muddle and work out. I stop at 45lbs, I din't feel the need for over torquing, maybe a Supercharged engine, but I diubt it very nuch.
 
hombres ruin said:
Thanks Ron and 19fordy great info. Is there harm in breaking a bolt or causing a water leak on a retorque?
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I found I needed THREE different length bolts for the Edelbrock heads on my 8BA. There are the usual long and short bolts, BUT there are also a handful of blind threads in the block, threads that don't go all the way through the metal. You can find them by poking a screwdriver into all the threads.

If you put too long a bolt in one of those and try to torque it down, you could cause damage to the threads or even the block. Find these and make sure the bolts you use in them do not bottom out.
 
If the sealant you used on the head bolts is the type that remains "sticky and soft" you probably won't have any leaks. I don't know of any other "issues." At this point your best bet is to retorque the head bolts and then check for any leaks.
 
Ol' Ron>>>When torquing>>>I stop at 45lbs>>>

Ditto. Then continue to re-torque till they stabilize at 45.

Jack E/NJ
 
I will start to retorque at 35ft lbs. I just want to seal the heads to the gaskets to rule out any leaks. Once I do 35 then should I go to 45? Remember the bolts are already in the head. When doing this should I follow the same rules,like torque down cold them go up to op temp let cool and retorque?
 
I doubt you will get any movement at 35 lbs if they were properly torqued initially. Start at 45. Best way is to back off slightly and then go to 45
 
CC33 said:
YES!!! At 55, I caused a crack and water leak into the cylinder. DO NOT OVER TORQUE.
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The Merc manual says that 65-70 ft. lbs. is correct for the stock cast iron heads. Would that much torque also possibly create a crack as you mentioned?
 
It could also break bolts and strip threads. I don't kow if 45 lbs is the factiry autherised torque settings. But, I've been doing this for over 50 years, this doesn't mean I'm right, just old. Besides you end up with more clamping force than a blown Hemi on nitro.
 
ron, the bolts have been in the heads for a while,i have never had a water leak but i feel that there maybe a small leak from the gasket not a blown gasket.So i want to retorque and get a good seal.The question of retorquing of bolts already in the heads seems to be a topic that has a grey area.Has anyone out there actually done it and if so how did you go about it?
 
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