Why are my head bolts different lengths?
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Jonah D'Avella
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Why are my head bolts different lengths?
My head bolts are different lengths, is that ok?
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TRDxB2
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Re: Why are my head bolts different lengths?
Doubtful. Low, high or accessory head?
Low head bolt 2-3/4" from under the head to the end of the bolt
High head bolt 3-1/4" from under the head to the end of the bolt
Are the bottom of the holes in the block cleaned out thoroughly? Maybe why someone used different ones.
Last edited by TRDxB2 on Thu Feb 15, 2024 1:23 am, edited 1 time in total.
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Jerry VanOoteghem
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Re: Why are my head bolts different lengths?
Probably not. It would be best to order new bolts and be sure they go in at least 1-1/2 diameters. Meaning 1.5 x 7/16" = 11/16". 3/4" or even more would be nice too. However, be certain that they do not bottom out in the cleaned-up threads before reaching the final torque.
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Jonah D'Avella
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Re: Why are my head bolts different lengths?
I checked and they looke to be the same length, but the threads are different lengths. I cleaned and ran a tap through all the holes
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Norman Kling
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Re: Why are my head bolts different lengths?
Two important things. 1. Bolts should all be the same height when screwed all the down in the block. 2. The threads should not end before the bolt bottoms out. If this is so, try the bolts in the head and block without the gasket. The heads should go down far enough to touch the head when installed without the gasket. If all these are true, you can install the gasket and it will have a turn or two to torque the head. Note, if one of the bolts bottoms out before it is all the way down, the torque wrench will read full torque when it bottoms out, but it might not be pressing down the head all the way. If you shorten the bolt, be sure to shorten them all so if they get mixed up, it will still tighten all the way down, or you can do like I did and always use a washer on the bolt in that location.
Norm
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DanTreace
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Re: Why are my head bolts different lengths?
The later nickel plate dome head bolts have a little shorter thread length. But only a small lower section of the threads go into the engine block.Jonah D'Avella wrote: ↑Wed Feb 14, 2024 4:09 pmI checked and they looke to be the same length, but the threads are different lengths. I cleaned and ran a tap through all the holes
The best way is always the simplest. The attics of the world are cluttered up with complicated failures. Henry Ford
Don’t find fault, find a remedy; anybody can complain. Henry Ford
Don’t find fault, find a remedy; anybody can complain. Henry Ford