winter maintenance
#1
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From: rock Island wa
I plan on pulling my stainless marine manifolds to pressure test and check all the internals as well as a peek at exhaust exits to look for any signs of rust. What is the torque spec upon reinstalling . Thanks , ken
#5
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From: wisconsin
For a 3/8-16 with a minimum of .5625 thread engagement, I would go 30ft lbs. But the key is... if you use new gaskets, you must let the manifolds heat cycle retorque, and do it once again. It all depends on the gaskets and fasteners used. You can't go wrong with letting the manifolds or headers for that matter heat cycle, torque and repeat. I know some guys will chime in and say... I only torque them once and never had a problem... well good for them. If you understand what happens with the gasket getting crushed as the heat expands the head, manifold or header, then cools down and guess what happens? Yup the bolts are not always still tight. Cometic makes a MLS gasket that you can get away with only torqueing once, because it acts like a spring during expansion and contraction.
#7
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From: rock Island wa
Thanks, I don't want to undertighten or over tighten and snap it off. Not sure what gasket is in there now as I've not removed them before. Looks like I have a lot more time now, but a lot less money.
#8
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From: Ft. Worth TX
Bare min for some Aluminum Exhaust Manifolds are 25 ft lbs and some list 30 ft lbs max . I would do a 3 pass tightening. And what was already posted - let a couple of heat cycles take place and recheck torque specs when cool.
I would torque them to 30 ft lbs max and use quality gaskets.
If I recall correctly (I think) SM might recommend 28 - 30 ft lbs
I would torque them to 30 ft lbs max and use quality gaskets.
If I recall correctly (I think) SM might recommend 28 - 30 ft lbs



