One thing your comment doesn't consider, Paul, is that American machine
shops have been putting hard seats into heads to combat the effects of
no-lead fuel since the late Seventies. I gather the change-over from leaded
in England is a relatively recent thing so it could be that English machine
shops are not yet sufficiently aware of what is needed.
I've been having hard seats fitted into MG heads for over 20 years and have
never had any problems, nor have I heard of anyone else doing so. Let's not
be scaring Aaron with possibilities of problems that are highly unlikely!
Lawrie
British Sportscar Center
----- Original Message -----
From: "Paul Hunt (T)" <paul.hunt1@blueyonder.co.uk>
To: "Aaron Whiteman" <aaronw@wsu.edu>; "MG Mailing List"
<mgs@autox.team.net>
Sent: Wednesday, January 07, 2004 1:18 AM
Subject: Re: head advice needed
> One thing to be aware of is that putting hardened seats in a head
introduces
> a thermal break that makes the seat and valve run hotter than before. The
> seat and valve material should be chosen with this in mind, but if
cheaper,
> although still harder materials than the original are used you can get
> problems. This is at least the third case of problems with a modified
head
> I have come across in recent months.
>
> PaulH.
>
> ----- Original Message -----
> From: "Aaron Whiteman" <aaronw@wsu.edu>
> To: "MG Mailing List" <mgs@autox.team.net>
> Sent: Tuesday, January 06, 2004 5:28 PM
> Subject: head advice needed
>
>
> > In the 3 degree heat last Sunday, I discovered that I have no
> > compression in my #2 cylinder.
> >
> > I have the original 1975 18V block, with an earlier head. I have no
> > idea what specific year the head is for, but it lacks air injection
> > ports. The previous owner told me that the engine was rebuilt with
> > valves and seats that were compatible with unleaded fuel.
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