exhaust manifold bolts

[dmiller]

i'm deaf as a stone, so maybe some excuss. also, this probably happened over time, i just got used to it gradually happening.

took a fellow for a ride couple of days ago, his comment was "didn't i hear the leaking exhaust manifold?"

sure enough, several bolts had backed out completely, lost forever, and most of others were loose.

i guess i'd just become used to the barking under the hood, and should have known better.

bolts are installed, and the under hood is quiet again. but what does one do to prevent this from happening, or is it necessary to frequently tighten the bolts?

what do the factory engines have that prevents the bolts from backing out?

i used neverseeze when originally installing. and on the replacement bolts. was this wrong?

i'm considering using high temp silicone to put only on the heads of the bolts when they are installed tighly, to prevent them from backing out. is that OK? feasible?

i don't think there is enough working room to safety wire them. but a thought i'm considering.

any help is appreciated. just be sure to speak loudly so i can hear you.

thanks.

doug

[pgermond]

Tightened them up about every 50 mi. on a new install. 3x's ought to do it. They will snug up and should stay put. If you have aluminum heads use anti-cease (sic?). Whenever mine is in the air (on stands) I check the header bolts - as I said, after 150-200 mi they have stayed where they are suppose to. If you have lost bolts and your valves aren't warped and/or haven’t blown an exhaust gasket, well, you must be living right.

Good luck!


Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

[dmiller]

thanks.

after reinstalling lost bolts, it seems snug, and engine runs well. so maybe living rite.


doug

[Eric Miller]

I had ARP ss bolts and replaced them with a split bolt with a set screw in the center when I had the headers off this winter.

Eric Miller

[lonnie]

Mine are lockwired.
Lonnie

[eliminator]

If you have steel heads you will have to constantly tighten them. The cooling rate between the aluminum heads and headers are about the same so once they are tightened several times they don't need alot of maintenance. On the other hand the steel heads and headers have completely different cooling rates and require running through the header bolts quite frequently. Thread lock or any other type of material wont help. We have had a few discussions off the Forum about this issue. The guy's with experience tell me they have used everything tp secure the bolts (short of safety wire) and it doesnt help.

Rick
#4279405

[lonnie]

Rick
I got my car in 98 and the bolts were safty wired. I the guy I got it from said he had removered the safty wire once but put it back on because they would not stay tight.In the time I have had the care they have not been tightened.
Lonnie