Thread lock on crank case to cylinder barrel studs

[Anvill]

Hi all,

I am getting my MKIII bottom end back together and had a question about using locktite on the studs going into the top of the crank case to secure the cylinder barrels. I'd imagine it would be a good place to use something since they can't be retorqued once the barrel is in place. What would you guys recommend to use here?

Thanks,
Anthony

 

[ashman]

Have never used any thread lock on the engine studs and have rebuilt mine and a few other Norton's over 48+ years and I still using all my original studs and nuts, never had a stud come lose yet.

 

[DennisMo]

I can't see that blue loctite would hurt.
Dennis

 

[marshg246]

I always use Blue (medium) on all crankcase studs. It is very annoying when a nut gets stuck the stud and then the stud comes loose rather than the nut. Also, if using stainless steel studs, you either must use anti-seize or Locktite if you ever need to get the studs out and I don't consider anti-seize the best in that situation.

I also double nut them and put them in firmly - but don't over tighten!

 

[DennisMo]

What will you use for gasket sealant? And what did you use on the crankcase halves.
I have yet to rebuild my engine but one day it may need it
Thanks
Dennis

 

[Anvill]

What will you use for gasket sealant? And what did you use on the crankcase halves.
I have yet to rebuild my engine but one day it may need it
Thanks
Dennis

For crank case halves a lot of people will recommend Threebond, Hondabond, or Yamabond as interchangeable options. They are a solvent based non-setting sealant. I used Permatex Motoseal, which is what's available locally for me and seems to be very similar.

Gasket sealant I haven't used much of to be honest, though I did buy some Permatex tacky gasket sealant today to install my CNW reed breather. Matt recommended to use a gasket sealer on the gaskets in his instructions and that seemed the best option in the store. It's a little messy but seemed to work ok.

Anthony

 

[DennisMo]

Thanks!

 

[marshg246]

What will you use for gasket sealant? And what did you use on the crankcase halves.
I have yet to rebuild my engine but one day it may need it
Thanks
Dennis

Usually nothing on gaskets except when putting the head on an 850, I smear some RTV on the two 5/16" studs per AN's advice. I also out a VERY thin smear on both sides of the composite gaskets around the pushrod tunnels but make sure it is not on the fire rings. They sell/recommend: https://andover-norton.co.uk/en/shop-details-2/18674 and I use that, but I doubt that it matters which RTV.

Sometimes when the gorillas have been at the timing cover, I'll use Copper Coat on both sides of a new gasket: https://a.co/d/cyMPrYz and let it dry before assembling. It seems to help, and the cover is no harder than usual to get off.

I'm different than others. I use Permatex Aviation Form A Gasket #3: https://a.co/d/h56dZnW Every motorcycle engine I've build in the past 52 years I've used the same thing. My Triumph 500 I build from junk in 1971. It never leaked and when I split the cases a few years ago, they came apart without problem and cleaned up with denatured alcohol. On the contrary, I took apart a Norton 750 engine last week that had some grey sealer. It took me three hours to split the cases that were leaking! I still don't have the old sealer off and there were chunks of it in the sump.

 

[Dan1950]

For crank case halves a lot of people will recommend Threebond, Hondabond, or Yamabond as interchangeable options. They are a solvent based non-setting sealant. I used Permatex Motoseal, which is what's available locally for me and seems to be very similar.

Gasket sealant I haven't used much of to be honest, though I did buy some Permatex tacky gasket sealant today to install my CNW reed breather. Matt recommended to use a gasket sealer on the gaskets in his instructions and that seemed the best option in the store. It's a little messy but seemed to work ok.

Anthony

For metal to metal joints ( my 850 had no gasket at the base when I tore it down) I use loctite 518. When there is a gasket I use the old standby, spray copper coat.