Skip to main content
English French German Italian Spanish

Exhaust head nut

Forums

1947 model 18. Can anybody advise on removal of the exhaust head nut. It has possibly been there for 60 years. I have tried heat, gentle tapping, a chain filter removing tool. I am not expecting to get it out in one piece! Does anybody recommend dismantling it with a Dremel or die grinder. Another method could be beads of weld to shrink nut slightly. Any one tried these ideas?

Dean Ghest

Permalink

Soak the joint with a solution of mild acid for between 24 and 48 hours. I like to use a diet cola but there are plenty of similar acidic solutions which should work just as well. The acid will get between the metal surfaces and gently dissolve away the gunge that is holding them stuck together. After the soaking apply a little heat to expand one of the surfaces and perhaps add a blast of WD40 or a similar lubricant to ease any friction.

Permalink

After a good soak ,if the exhaust pipe is still intact ,release any frame fixing and use the pipe as a lever in conjunction with the nut spanner(at least a foot long). My exhaust spanner is 2ft long!.Never had one come loose.

Permalink

which I've had for many years. A big brute of a thing. But in your case I'd definitely soak in plus gas for a week or so before trying.

Permalink

Have invested in 3 quids worth of genuine Diet Coke. Tried commando spanner, heat, had WD periodically sprayed on over last 2 to 3 decades (hang head in shame, yes that’s how long it has languished in my care). It’s tight. Problem is holding as head on bench at present held using clamps. Exhaust is long since gone. Thanks for replies.

Permalink

Are you running the engine until it gets really hot and then trying?

or, have you tried heating it in an oven until it gets up to 300-350 deg F and then clamping it in a large vise so you can apply a lot of torque to the nut?

You will probably have to figure out beforehand how to clamp it in the vise with some strips of wood so you do not harm any sealing surfaces.

A spare set of hands and some good kitchen gloves will help your hands.

p.s. Do this when the wife has gone to visit her mother........

Mike

Permalink

Sounds like it's being a proper stubborn git!

Just be patient and don't damage the head. As a last resort, if all the other methods fail, you could consider "Spark Erosion".

I have not used this myself, but I have heard of it working for other people.

I'm not entirely sure how it works, but I imagine it employs an arc something like in electric welding to vaporise the offending part. I understand it leaves the surrounding metal unaffected.

No idea where this service can be obtained, but hopefully others, better informed on here could expand on this idea?

Good luck

Gary

Permalink

Heat head in oven  for 30 mins on 200   remove  place in vice   and pour cold water over nut. and then give it some,  watch out for steam! 

Permalink

................ works well. It will shrink the nut's OD if done sufficiently. TIG will work best I believe. Spark erosion is an expensive solution unless you have a friend with the equipment.

 


Norton Owners Club Website by White-Hot Design