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Discussion Starter · #1 ·
What is the best way to keep header bolts from backing out?
Stage 8, lock washers, etc.
Thanks, Chris.
 

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Then they will stay put?
Thanks, Chris
 

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In a general sence they will but only if the gasket is fully seated and compressed, and then the bolts are tightened.
9 times out of 10 lock washers will not work on exhaust manifolds of any kind. What happens is they are accidently installed correctly...

I use regular flat washers most of the time unless the customer is "Certain" that lock washers will work like they alway's have for him...

Tighten them down and drive it for a few day's, re-tighten them and do it a couple day's later just for gits and shiggles.

FE
 

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stage 8. put them on, run it to operating temp. let sit overnight. retorque and install the locking things and your done. they were on my bronco for 7 years and never had a leak. before that i would have to tighten every week or so. and even then they would still fall out once in a while.
 

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another thing to consider is the actual bolt itself....the best bolt for exhaust, is your regular run of the mill grade 5 bolt, because of the softness of the bolt, it expands and contracts more like cast iron, and believe it or not, aluminum as well....never use grade 8 bolts, they'll back out every time......don't confuse this with stage 8 bolts, look at the top of the bolt, if there's 6 marks on it, it's a grade 8, if there 3 it's grade 5......
 

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I know some say don’t use lock washers but I do. I use an allen head with a low boy type lock washer. There for use in a counter bore hole for like fixtures. I put them in two years ago and never even checked them since. No leaks hear. I do a visual to see is all and that’s it.
 

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I tightened mine for the first 100 miles or so, just gave them a check when I got home, and they've stayed put ever since. In fact, I don't look forward to taking them out.


Make sure you put anti-seize on the bolts, especially if they are in aluminum heads.
 
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