Yep - I always make a point of replacing these new any time I take
them off. I never have to tighten them as a result.
I would use steel nuts here, even with anti-seize. No need if you use
new brass nuts.
Alan
On 6/15/08, Bob Spidell <bspidell@comcast.net> wrote:
> I've gotten so many helpful replies to my requests today I thought I'd
> pass along an observation I made before my last road trip.
>
> I've had trouble getting a good, persistent seal on my exhaust
> manifold-to-downpipe flanges. The flanges are flat, and I've tried both
> the copper- and steel-faced gaskets; neither lasts for long. The brass
> stud nuts keep loosening, and I've gotten into the habit of tightening
> them frequently. When going through the car prior to the trip, I was
> tightening the nuts (again), and one of them stripped (moment of panic:
> is it the nut, or the stud that's stripped???!!!). Anyway, I replaced
> the nut with one of the many spares I keep and headed out on the trip
> (3,600 miles in 9 days). Most days, I would lay on my back and tighten
> the nuts with a ratchet, two extensions and a deep socket before
> starting the day's driving.
>
> What I noticed: the nut that was replaced stayed tight, while the other
> 5 were always various degrees of loose at the start of the day. I
> surmised that the threads on the soft brass nuts either erode or
> distort, making it impossible to keep good torque/stretch on the studs.
> It could be that brass nuts should not be re-used--the
> new-when-installed, never tightened brass nuts on my head-to-exhaust
> manifold studs have been fine for many miles--but I've never heard that
> anywhere.
>
> My recommendation is to not re-use brass nuts on exhaust studs, they
> aren't cheap nor are they particularly expensive, but they don't seem to
> be reusable. Alternatively, you could use steel nuts with anti-seize,
> but I don't know if this is a good idea (anyone?).
>
>
> bs
>
> --
> *******************************************************************
> Bob Spidell San Jose, CA bspidell@comcast.net
> *******************************************************************
> _______________________________________________
> Support Team.Net http://www.team.net/donate.html
>
> Healeys@autox.team.net
> http://autox.team.net/mailman/listinfo/healeys
>
> You are subscribed as healey.nut@gmail.com
>
> http://www.team.net/archive
>
--
Alan
'52 A90
'53 BN1
'64 BJ8
_______________________________________________
Support Team.Net http://www.team.net/donate.html
Healeys@autox.team.net
http://autox.team.net/mailman/listinfo/healeys
http://www.team.net/archive
|