Exhaust manifold bolts - Should I use Locktite?

[GrUmPyBoDgEr]

I just used some of these myself on my S3 SE (down pipe to manifold) due to access problems, 5/16 unf, 3/8 socket with 1/4 drive and bit of copperslip on the threads.

Almost identical to what I've used although mine being on a Zetec are M8 of course.
Mine are silver plated, do yours have any form of anti-galling coating?
Double Hex' is the way to go, being flank drive rather than the "point drive" of a hexagon nut; space saving regarding smaller socket size is also a big plus but I expect that the pictured K-nuts will also offer similar reduction.

Cheers
John

Hi John

Someone said open your hand and dropped a bunch in my palm, I took 8 and Wow life's been great! Yes they were free so I used them. Had I bought them maybe I would have gotten a 12 pt. version as almost all nuts are cheap to buy new.

Ha, ha; I paid the same for mine, but don't tell anyone will you
Things will be very different now that I'm retired, I'll have to pay for everything

[types26/36]

Ha, ha; I paid the same for mine, but don't tell anyone will you
Things will be very different now that I'm retired, I'll have to pay for everything

I had to pay for mine but are cheap enough off EBay....basically the price of a pint for five nuts:
http://cgi.ebay.co.uk/Pack-5-5-16-UNF-A ... 1e646e95bd

[Steve G]

Thought I would post here rather than start a new thread. I finally got the engine back together yesterday and went for a drive, I reused my exhaust manifold gaskets because they hadn't been in use long (<100 miles ) and I forgot to order new ones. I have the steel stud with brass nut set up. There appears to be a leak from one of the ports, on the number two port the nut on the right jams against the weld on the manifold and it makes it very hard to tighten. So I have a couple of questions;
Does an exhaust leak sound like a tapping noise under load? It does sound more pneumatic than metallic but I'm not sure.
After replacing the gaskets, will fitting SS spring washers, like the ones on the carburettor side be advisable? After the manifold heated up the nuts needed tightening again, which was counter intuitive as I would have thought they would become tighter after heat expansion. I think the spring washers may solve both these issues. I have a vague memory of the original brass nuts having a modified one in this location where the corners were rounded off on one half of the nut.

[rgh0]

Yes a gasket leak sounds like tapping noise

The brass nuts should have a little antisieze on them. Spring washers are no good as they will loose their tension under the temperature of the manifold. The nuts loosen a little on heat cycling compresses the gasket and they should be retensioned after a few heat cycles

If the brass nuts are not seating proplerly on the manifold flange try to grind a little of the weld away so it sits flat.

cheers
Rohan

[Steve G]

Yes a gasket leak sounds like tapping noise

The brass nuts should have a little antisieze on them. Spring washers are no good as they will loose their tension under the temperature of the manifold. The nuts loosen a little on heat cycling compresses the gasket and they should be retensioned after a few heat cycles

If the brass nuts are not seating proplerly on the manifold flange try to grind a little of the weld away so it sits flat.

cheers
Rohan

Thanks Rohan, glad I asked now, and very, very happy that it is a tapping noise. It sounded expensive at first! Maybe the last modified nut was a DIY job.