Head bolts
#1
Head bolts
Hi,
I am currently replacing head gaskets on a 1990 truck with a 3VZE in it. I stripped a head on a head bolt which required removal of the bolt in the middle(4th bolt step 2) of the 3 torque steps. I was able to get the bolt out with a BFH and pounding a 7/16 on the 12mm head. I replaced the stripped bolt with a new one and completed the installation. I decieded to use a torque wrench to check final torque of the bolts as the installation was completed. I estimate that the bolts were torqued between 75-90 ft lbs at the end of the third step. The bolts I used were from engbldr and are not the torque to yeild OEM bolts. My question is should I remove all the head bolts and retorque them or leave them as is? Can you over-torque a headbolt on a 3.0? Thanks.
I am currently replacing head gaskets on a 1990 truck with a 3VZE in it. I stripped a head on a head bolt which required removal of the bolt in the middle(4th bolt step 2) of the 3 torque steps. I was able to get the bolt out with a BFH and pounding a 7/16 on the 12mm head. I replaced the stripped bolt with a new one and completed the installation. I decieded to use a torque wrench to check final torque of the bolts as the installation was completed. I estimate that the bolts were torqued between 75-90 ft lbs at the end of the third step. The bolts I used were from engbldr and are not the torque to yeild OEM bolts. My question is should I remove all the head bolts and retorque them or leave them as is? Can you over-torque a headbolt on a 3.0? Thanks.
#2
Yes you can over torque them, to a point that they can get stress fractures eve to the block threds, If you have gone by the book torquespecs your already better off since you used aftermarket bolts.
Make sure they are all torqued to the same lbs, 75-90 is kinda brawd pick a # and stay with it.
Something I saw on here you might want to do another search for it...
Somone used aftermarket bolts and did a slow fine torque and got them all to 115lbs using like 2lbs steps.
Dont remove them if you have to go tighter, If you did I suggest getting new gaskets again.
Make sure they are all torqued to the same lbs, 75-90 is kinda brawd pick a # and stay with it.
Something I saw on here you might want to do another search for it...
Somone used aftermarket bolts and did a slow fine torque and got them all to 115lbs using like 2lbs steps.
Dont remove them if you have to go tighter, If you did I suggest getting new gaskets again.
#3
Only removed the stripped bolt
Thanks for the reply. I only removed the stripped bolt. I then installed the new bolt, torqued to 33#s and then 1/4 turn and completed the torqueing the rest of the bolts the 1/4 turn X 2.
I noticed that the torque wrench was not clicking at the same point for each bolt (according to the paint marks). I went to the 180 dergrees on a couple and the torque was only at 75#s where others reached 90#s at the 180 degrees. The threads were clean and oiled. Is this cause for concearn?
Another question would be if I pick a torque load such as 90 #'s how much past 180 degrees should I go if it does not click the torque wrench?
I also wanted to note that the bolt head stripping was not because of the bolt being bad but due to a worn 12pt socket that I used. If I was to do it over I would still use the head bolts from engbldr.
I noticed that the torque wrench was not clicking at the same point for each bolt (according to the paint marks). I went to the 180 dergrees on a couple and the torque was only at 75#s where others reached 90#s at the 180 degrees. The threads were clean and oiled. Is this cause for concearn?
Another question would be if I pick a torque load such as 90 #'s how much past 180 degrees should I go if it does not click the torque wrench?
I also wanted to note that the bolt head stripping was not because of the bolt being bad but due to a worn 12pt socket that I used. If I was to do it over I would still use the head bolts from engbldr.
Thread
Thread Starter
Forum
Replies
Last Post
kgcwb44
86-95 Trucks & 4Runners (Build-Up Section)
4
01-29-2023 10:02 AM
GreatLakesGuy
The Classifieds GraveYard
8
09-04-2015 09:27 AM
whereAreMyPants
86-95 Trucks & 4Runners
2
07-22-2015 03:32 AM