retorque cylinder head or not ?

rpatton

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Last season I replaced the head gasket on my 1986 mercruiser 120. I milled the head and did all the right things.I ran it the remainder of the season which was only a few week with maybe 15-20 actual run time. That said do I need to retorque the head or just leave well enough alone. Thoughts anyone? Thanks
 

Bob_VT

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Re: retorque cylinder head or not ?

If you are that concerned pop the valve cover and go for it....... I would leave it alone if it is working.
 

rpatton

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Re: retorque cylinder head or not ?

Thanks for replying. That's kinda what I was thinking. Iv replace a whole lot of truck head gaskets without ever retorqueing and they have been fine.
 

achris

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Re: retorque cylinder head or not ?

If you used a 'non-retorque' gasket, don't touch it. If you used a standard gasket, you MUST re-torque it (should have been done after first warm-up)... Iron head/iron block... Must be warm to re-torque, and back each bolt out a little before torqueing.
 

rpatton

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Re: retorque cylinder head or not ?

I'm not sure if if is a non retorque gasket or not. It came from marine engine.com
 

Fun Times

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Re: retorque cylinder head or not ?

I'm not sure if if is a non retorque gasket or not. It came from marine engine.com
Most likely it's aftermarket. By chance do you still have a/the part number?
 

rpatton

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Re: retorque cylinder head or not ?

No sorry. Not sure now if I should leave it alone or retorque
 

Bob_VT

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Re: retorque cylinder head or not ?

Re-torque will not hurt it. Use a high quality torque wrench.
 

Fun Times

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Re: retorque cylinder head or not ?

With that engine model you have and the work done, you would be better to Re-torque vs not.
 

rpatton

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Re: retorque cylinder head or not ?

Quick question though. I should back each one off about a 1/4 turn and retorque one at a time in order with a warm engine correct??
 

achris

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Re: retorque cylinder head or not ?

Quick question though. I should back each one off about a 1/4 turn and retorque one at a time in order with a warm engine correct??

Correct...
 

rpatton

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Re: retorque cylinder head or not ?

Great thanks I'll take all the advise
 

Walt T

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Re: retorque cylinder head or not ?

Anything that gets you up close and personal with the motor even if it doesn't really need it is a good thing in my opinion. Check all the valve springs and keepers see if anything looks out of place, heck maybe even do a quick valve adjustment. Check spark plugs see if they look all nice n purty, general look over of the motor, steering, bilge for oil leaks water leaks, maybe take a simple box end wrench go over other bolts for intake and exhaust, brackets n stuff, never know what might be coming loose. Check the belt for any weird wear might indicate pulley alignment problems. Check the nut behind the wheel.
 

rpatton

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Re: retorque cylinder head or not ?

Great advise and I'll take a look
 

rpatton

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Re: retorque cylinder head or not ?

OK guys sorry to beat a dead horse here but I am taking the advice of you guys and retorqueing the head. But my problem is I'm trying to access the boat library And am unable to load it onto my screen. I'm looking for the torque spec and procedure. I did it the first time but just want to make sure to get it correct.can anyone help with the torque spec and procedure for RETORQUEING a 1986 mercruiser 120 2.5. Thanks
 

achris

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Re: retorque cylinder head or not ?

Warm the engine up. Remove the rocker cover. Move around the head bolts in the standard torqeuing sequence. Just crack the bolt loose and torque it up to spec, then move to the next one in the sequence.

Chris....
 

rpatton

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Re: retorque cylinder head or not ?

Great thanks Chris just wasn't sure if I should do it hot or let it cool off some. By chance do you remember the torque my book says 93ftlbs but its not a factory book and do not trust it.
 

Volphin

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Re: retorque cylinder head or not ?

Warm the engine up. Remove the rocker cover. Move around the head bolts in the standard torqeuing sequence. Just crack the bolt loose and torque it up to spec, then move to the next one in the sequence.

Chris....

I differ with Chris on this one. Most aluminum heads need re torquing... iron heads do not. And many head bolts today are TTY anyway. If you want to check them, then do so. I'd NEVER loosen one at all to recheck. YMMV
 

achris

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Re: retorque cylinder head or not ?

I differ with Chris on this one. Most aluminum heads need re torquing... iron heads do not. And many head bolts today are TTY anyway. If you want to check them, then do so. I'd NEVER loosen one at all to recheck. YMMV

This is not a 'modern' engine, it's 1986, of a design that goes back to the 40s or 50s. The reason you back the bolt off first is because they get 'stuck', and give a false torque if they are not cracked out first....
 
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