Head bolt stripped

Fri Mar 01, 2013 11:06 am

Hello! i am having a problem with the head bolt #8 .. i was doing a re tighten at 50lbs ft. when the bolt start to spin withouth reaching the final torque.. all the other bolts are tight at 50lbs-ft.. i put some loctite thread locker and rtv sealant to that bolt and try another time and the only torque i could get was around 7lbs, can i leave them like that?
Or i would have to put a helicoil insert? there was already a helicoil there, but it failed...
Thank you!

Re: Head bolt stripped

Fri Mar 01, 2013 11:27 am

Can you be more specific about the helicoil failure? Did it spin lose or did the threads in the cast iron strip out? Usually that stainless insert it pretty tough.

Rick

Re: Head bolt stripped

Fri Mar 01, 2013 11:32 am

nicolascub wrote:Hello! i am having a problem with the head bolt #8 .. i was doing a re tighten at 50lbs ft. when the bolt start to spin withouth reaching the final torque.. all the other bolts are tight at 50lbs-ft.. i put some loctite thread locker and rtv sealant to that bolt and try another time and the only torque i could get was around 7lbs, can i leave them like that?
Or i would have to put a helicoil insert? there was already a helicoil there, but it failed...
Thank you!


Yes it will require a heli-coil type insert. The Service manual calls for only 45lb of torque. You have stripped the threads in your block.

It is recommended that the torque is brought to 45 in steps. Say, 30-35 in proper rotation, then again to 45. If with lubrication a little less, the spec is for dry I believe.

Sorry
Dale

I missed the part of it was heli-coiled once. Either way it needs to come apart. be careful

Re: Head bolt stripped

Fri Mar 01, 2013 11:46 am

Dale's comment got me thinking more. I agree, the head has to come back off. Number 8 bolt goes into the water jacket, so whatever failed, you'll for sure have a water leak. If the cast iron threads are stripped in the head and you have a normal stainless coil for a helicoil, you may have to switch to the larger type insert that's available.

Rick

Re: Head bolt stripped

Fri Mar 01, 2013 6:46 pm

Thank you very much for the answers!
I took the head off, the bolt #8 was not heli coiled after all.. the block thread is what fail and came off.. so i am going to put a new helicoil there!
One more question, the engine has run for about 30 min, is fresh rebuild, the gasket is new but was very difficult to take the head off and some parts of the gasket is a little bend and divided in some points, for me is a pain to get a new gasket... i live in Argentina, can i use the same one and put rvt on all the spots where the bolts are so water do not flow up... i guess when the head tight against the gasket i will make the original shape again.. but i don't want to make a mistake. i prefer to hear
The shinny spots on the gasket are marks from the screw diver i used to unglue the gasket
from experienced people

Here are the pictures.
Image
Image
Image
Image
Image
Thank you very much

Re: Head bolt stripped

Fri Mar 01, 2013 7:02 pm

New head gasket.

To keep coolant from seeping past the head bolts, you can use a non hardening gasket sealer. RTV - perhaps but I would rather use a gasket sealer. I didn't provide a brand name for the gasket sealer/maker. You probably have a suitable gasket sealer on hand.

Re: Head bolt stripped

Fri Mar 01, 2013 7:53 pm

Nicolas, TM Tractor (a Forum sponsor) sells head gaskets and ships internationally. They might be a viable option for you to get a new one.

Bob