Retorquing Head Bolts

[bikemtn]

Mercruiser 3.7L
What is the correct process to retorque the head bolts? Do I loosen them first? I have a maunaul, but it just says to retorque them after break-in at their noted specs, but nothing about loosening them first.

 

[HT32BSX115]

Re: Retorquing Head Bolts

(loosening?) Short answer is no.

Just put a torque wrench on it and start with #1 and torque to rated spec and the stated pattern.


Cheers,


Rick

 

[bikemtn]

Re: Retorquing Head Bolts

Perfect....thanks guys! I did not think I would have to loosen them, but read on some websites to looosen like an 1/8th of a turn. That did not seem right, so I had to ask the experts here on the forum.

 

[bikemtn]

Re: Retorquing Head Bolts

Stupid question.....
Do I need to get a special socket for the bolts under the rocker cover? Nothing I have will fit under the rockers. I tried to find the shortest/thin walled sockets I have...

 

[Fishermark]

Re: Retorquing Head Bolts

Sometimes you need to loosen the rocker arms to get access to the head bolts. Just a FYI - did you oil beneath the heads of the bolts before torqueing them down? If not, your torque values are probably not accurate.

 

[bikemtn]

Re: Retorquing Head Bolts

I will try that...
I put a torque wrench on outiside bolts just to see how tight they were and they turned with 35#...So needless to day they need to be retorqued. I just want to do it correctly.

thanks

 

[Fishermark]

Re: Retorquing Head Bolts

If they turned with 35 pounds pressure then they were not torqued right to begin with. No way they loosened up that much.

 

[bikemtn]

Re: Retorquing Head Bolts

I agree. I am not really happy with the workmanship the people did on the rebuild. I would take it back to them, but my warranty expired, and I think I could do a better job anyway!!!

 

[bikemtn]

Re: Retorquing Head Bolts

When loosening the rockers should I put #1 tdc when I tighten them back up?? I do want to bend a rod or something.

I think the specs for the rockers are 20#?

 

[bikemtn]

Re: Retorquing Head Bolts

I went ahead and loosened the rockers and was able to torque the head bolts....and they were in fact a bit loose. I made sure to tighten the rockers back to spec per my manual (20#) when the valves were in the appropriate position. A word to all the folks that are on here and do not have a manual....Get one!! They are cheap and save you a ton of time!!!!!

 

[achris]

Re: Retorquing Head Bolts

... A word to all the folks that are on here and do not have a manual....Get one!! They are cheap and save you a ton of time!!!!!

Amen!!!