-- [ From: Bob Nogueira * EMC.Ver #2.10P ] --
Last month the BGT was running very badly. I did a compression check
and number two cyl. was at 0.
I pulled the head and found the valves sitting very deep in the seats.
Off to the macjhine shop and yes, the valves had receeded into what was
left of the seats.
The head had a valve job 40,000 miles ago.
My machinist said the valves and seats did not have enough meat left
and if he ground them again the job would only last a short while since
the valve faces were so thin they would errode quickly.
His explanation to me was that with each valve job you take more metal
off the seats and valves , the reduced metal allows the valve and seat
to get hotter thus causing pre ignition and erosion of the seat and
valve face, Thus with each valve job you reduce time to the next valve
job .
He said if I got 40,000 from the last one I was looking at 20,000 or
less to the next one unless I replaced the seats and valves.
Ever since 1974 when leaded gas was phased out I have heard of
replacing the seats and valves with hardened ones, but have never heard
anyone discuss the cost.
Since I have my invoice right here, I thought I'd post it just in case
there is someone else out there who, like me, has no idea what the cost
of hardened seats come to.
Fasten Your seatbelts please:
4 Intakes seats $50.40
4 Exhaust seats 63.24
head kit 49.95
4 stellite exhaust valves 38.00
parts total 201.19
Valve job :
(incl) Vat , Magnaflux
freeze plugs 125.00
Install 4 hard seats 40.00
mill head .010 68.00
ream guides 36.00
labor total 201.19
Governor Bush' s cut 16.58
Total-----------------------------------------$486.77
I have no idea how this compares with other shops but I will say the
machine shop I used specializes in building race engines ( Big blocks)
and he takes on my MG work only because the guys in the shop get a kick
out of working on my "toy" engine.
Needless to say I was somewhat taken aback at the cost since in the
past I have always paid 100 to 150 for a valve job.
-- REPLY, Original message follows --------
> Date: Saturday, 27-Jan-96 03:15 AM
>
> From: U. Goettsch \ Internet: (ulix@u.washington.edu)
> To: Bob Nogueira \ PRODIGY: (NKED65A)
>
> Subject: Re: Unleaded fuel and valves (was: F experiences, for some
odd
> reason)
>
> On Fri, 26 Jan 1996, Denise Thorpe wrote:
> > I've put 150K miles on the perfectly stock head of my '67 B and
never
> had
> > any problem using premium unleaded. Don't worry, be happy.
SNIP>
-------- REPLY, End of original message --------
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