#**! Exhaust Nuts

[Ray from Indiana]

A bad day

I decided I wanted to take the exhaust system off today for another reason.

I can't budge those darn exhaust nuts....despite having lubed them as a prevention this spring with Cu anti-sieze.
- used liberal amounts on everthing that touches
- no, I didn't torque to anywhere near the spec, just goodintite but wayyy looser than the BMW spec

I decided to leave them alone until this winter and cut 'em off then

Win some, lose some.

[Deleted User 62]

Try hitting your exhaust wrench with a hammer, a quick hit vs slowly applied pressure is sometimes what it takes to snap it loose.

[Kurt in S.A.]

I'd continue to let time and soaking work for you. Personnally, I'd leave the hammers in the tool box...if it doesn't spin easily, I'd be inclined to cut them off. I did my /7 heads and I'm not one of the "remove the exhaust nuts every year and regrease" kind of guys. They were on for near 30 years...that was because of the first time I took them off and used a hammer when I was a noob and before there was the Internet. This time, I didn't hesitate at all...I got out the hacksaw. For me, that wasn't that easy of a job. It's not like you can get big strokes with a hacksaw...I didn't want to resort to a Dremel...I usually get in trouble with those. But slow and steady finally got it done. Glad I did.

Kurt in S.A.

[montmil]

Saw 'em off, Ray. New "butterfly" nuts are w-a-a-a-y cheaper than thread repair costs on the head's exhaust stubs.

Leave the dead blow hammer in the toolbox. If a good tug doesn't get the nuts loose, it's over.

[Ray from Indiana]

Like I said originally my plan was to cut them off, sorry, no BFH for me.

But then I went for a ride. Now I knew I put LOTS of anti-sieze on those suckers so when I got back, I put on the gloves and got the wrench, gave it try, and they came loose with a lot less of arm power than I was trying when the engine was cold. WTF?


Luckily no galling of the head spigot. I have to think this situation through.

[Jean]

The nut expanded more than the threaded spigot on the head.
High School Physics demonstration...
I guess they don't do REAL stuff like that anymore.

[Ray from Indiana]

Hey Jean
No need to insult me. Yes I had high school physics back in the 60s and went well beyond high school.

The way I learned physics if you take two objects of same material and approximately same dimensions, the hotter one will expand more than the cooler. Seeing as the spigot should be hotter than the finned exhaust nut which loses heat by radiation and convection would you not expect that the nut has expanded less than the spigot? And if that is true, shouldn't the nut be harder to remove?

I'm thinking the copper anti-sieze really didn't lubricate until heated. BTW I did hit these with my heat gun before I chickened out about going further. That should have increased clearance between the nut and the spigot but that didn't work

[Jean]

I was speaking of the demo with the steel ring and the solid ball.
At first the ball will not go thru the ring. BOTH are heated, The Ring expands more.
The ball passes thru.
It has to do with...oh hell.
It does work.

[Major Softie]

Hey Jean
No need to insult me.

A little over-sensitive, Ray?

I don't think that was really an insult - at least, not an insult to you. Perhaps it was a bit of an insult to our modern education system.

I know, you had a really bad day, but it all turned out all right. Right?

[Jean]

Going for a ride is usually a good way to fix a bad day unless your side covers get lost!!