FJ60 Exhaust Flange Bolts

[Nathan Kuwitzky]

I replaced my flange gasket and closed up
my exhaust leak. The bolts were looking pretty rough so I picked up some new ones from ACE hardware (I’m guessing it may be a softer metal than OEM though). It’ll be good for a couple of days and then the bolts are gradually loosening and my leak comes back. I’m guessing they loosen from the constant heat expansion cycles of the exhaust. I think I’m going to pick up a set of OEM bolts from the Toyota dealer today. Can anyone recommend what I can put on them to keep them from backing out again? Most threads say to apply anti-seize but that seems like the opposite of my problem. The lock tights that I’ve seen isn’t rated past about 400 degrees. Any thoughts or recommendations?

 

[tucson_sailors]

Usual answer would be split washers or a second nut, but not sure on the exhaust bolts. If you try the second nut option (if there is enough thread) then I would think the anti-seize on those at least becomes a good idea to allow you to *remove* them off of the other set.

$.02

Glenn in Marana

 

[Nathan Kuwitzky]

Ya, I read generically about people using a second nut but that’s not really an option when I’m using bolts. I’ve been using split washers but I read something else that said usually the heat will render them useless and that it’s better just to use the bolts by themselves. I’m guessing the metal from my ACE bolts is softer and not heat rated. I just ordered the OEM bolts for $7 each from the dealer. I think I’m gonna try that and see if it works.

 

[g-man]

Exhaust flange to me means at the collector where the exhaust pipe mounts to the exhaust flange w/3 studs and a round gasket. I bought import (toyota/nissan/honda) studs at Advance auto ...they worked good but the brass nuts were too soft and stripped partially when tightened. I replaced them with steel nuts and have not had a problem. Or are you talking about the cylinder head to exhaust bolts?

 

[tucson_sailors]

Ya, I read generically about people using a second nut but that’s not really an option when I’m using bolts. I’ve been using split washers but I read something else that said usually the heat will render them useless and that it’s better just to use the bolts by themselves. I’m guessing the metal from my ACE bolts is softer and not heat rated. I just ordered the OEM bolts for $7 each from the dealer. I think I’m gonna try that and see if it works.

D'oh! Was thinking exhaust studs, not bolts for the dual nut theory. I agree with G-man on generic import parts if OEM weren't avail. Case hardened grade 8 or better would most likely be the automotive spec, the ace stuff as you have found is usually not of that grade.

$.02

Glenn

 

[OSS]

When new fasteners are used both male & female (studs & nuts) antiseize grease isn't needed or required or even recommended. Toyota doesn't use it on anything

 

[Nathan Kuwitzky]

Exhaust flange to me means at the collector where the exhaust pipe mounts to the exhaust flange w/3 studs and a round gasket. I bought import (toyota/nissan/honda) studs at Advance auto ...they worked good but the brass nuts were too soft and stripped partially when tightened. I replaced them with steel nuts and have not had a problem. Or are you talking about the cylinder head to exhaust bolts?

Actually I was referring to the exhaust pipe flange that mounts to the bottoms of the manifold. It has 3 bolts and a donut gasket. No studs or nuts.

 

[Spike Strip]

If you're asking about the nuts at the top of the downpipe, where it bolts to the exhaust manifold, you need 'stover' or crimped nuts that lock when torqed and won't come loose.

I used some JIS copper ones from BelMetric.com but the steel OE work well. I also use high-temp copper anti seize.

 

[g-man]

Actually I was referring to the exhaust pipe flange that mounts to the bottoms of the manifold. It has 3 bolts and a donut gasket. No studs or nuts.

You should post an image of the bolts you have there. They should be studs with nuts on them. But Prob been touched many times so P.O. did something screwy. How did you manage to order "toyota bolts" for exhaust donut studs? You may have ordered the exhaust manifold to cylinder head bolts. And they will be wrong.

 

[g-man]

Go to an auto parts store and get a bag of 3 or 4 studs w/nuts for japanese import vehicles. Put the side with the longest length of threads into the manifold. Should look like these:

 

[g-man]

Make sure the donut is all the way against the manifold and feel with your hands to make sure the gap around the flange between the manifold and the exhaust pipe is even and narrow before tightening the nuts. It is possible to pinch the donut and ruin it and end up with another exhaust leak.

 

[Nathan Kuwitzky]

Go to an auto parts store and get a bag of 3 or 4 studs w/nuts for japanese import vehicles. Put the side with the longest length of threads into the manifold. Should look like these:

View attachment 1990515

Oh wow!! That’s the problem! The PO must have removed the studs and just put bolts back in so I now have bolt heads under my flange instead of studs and nuts! Thanks for the help!