manifold bolts

[54fordguy]

can anybody tell me to what foot lbs. to torque manifold bolts

 

[Tom Wesenberg]

ZERO!!!!!!!!

Don't use a torque wrench, just use common sense and about a 6" box wrench and make them tight enough to seal.

 

[700rpm]

And retighten them after the engine has warmed up and cooled down and warmed up again. Make sure your washers are installed with the cupped side toward the block, crown side to the nut.

 

[54fordguy]

thanks for the info.too late we cracked both manifolds this afternoon real bad day.

 

[glenn in camino]

I always put the intake and exhaust manifolds together and have the whole assembly surfaced. Haven't cracked one yet.

 

[AL in NY]

Torque value on those four nuts is 45 ft/lbs.............................I always turn the manifolds over after surfacing and mill the outside surfaces of the washer taps to the same height.

 

[700rpm]

thanks for the info.too late we cracked both manifolds this afternoon real bad day.

54---
I'm sorry this happened. But the good news is manifolds are not hard to find. If you were on the left coast, I have a set I'd just give you. Don't beat yourself up over it.

 

[Marco Tahtaras]

thanks for the info.too late we cracked both manifolds this afternoon real bad day.

I'm truly sorry to hear that. However there can be more than one contributor. To hopefully avoid a repeat I'll list a few things I've seen folks do.

1. Simply over tightening. Some folks have a "tighter is better" mentality which is always risky behavior. Even using torque charts (which didn't exist in Model A days) focus on the fastener and NOT the application.

2. installing manifolds which are severely mismatched from warpage and uncorrected.

3. Attempting to install gland rings which don't align, or with manifolds which have been surfaced leaving insufficient counterbores for the gland rings so the exhaust manifold can't draw in on some or all ports.

4. The worst (and not uncommon) is installing the domed clamps (washers) upside down with the dome facing the manifold. This is certain to break at least one manifold mounting flange!

 

[54fordguy]

i want to thank all u guys for responding and all the great information when we put together next time, i feel like we will have a better result thanks again.

 

[Milton]

i want to thank all u guys for responding and all the great information when we put together next time, i feel like we will have a better result thanks again.

Strange thing, this morning while browsing I found a torque recommendation of 35-45 ft lbs. I have never torqued those particular nuts but I do use extreme care to tighten them evenly. Like you say next time will be better, once burnt, twice cautious.