>> ... The resultant valve seat was rather wider
>> than it should have been (which is bad)...

>> worked.

> Sometimes. The general problem with lapping seats is that
>  a)  It wears the valve face
>  2)  The valve (at least exhaust valves) are at a much higher
>       temp than the seat, causing the lapped face of the valve
>      to expand right off the presumably wear-mated seat in
>     many cases. At least with a narrow seat.

It was an exhaust valve.

> I bet you didn't use a torque plate either...   :)

A who what?

This was about 1976.
Car was  1958? Sidevalve Hillman Minx. (53?)

Compression was probably about zero on one cylinder. Car was probably
about 20 years old at that stage :-). The choice seemed to be
expenditure and effort beyond what an old deadish car was worth, or an
attempt at a "fix" that may work, took minimal effort and was "fun". A
"real" mechanic would have frowned severely at the idea.

I had an old geared down disk dictaphone motor. Originally these
recorded speech on an LP record sized disc shaped sheet of magnetic
"tape" type recording media. The advantage over tape was manual random
access - pick up the arm  and move it. Wow !!!

AFAIR motor had about 1 RPS output or less. Car in residential garage
with wooden exposed rafters. Mounted motor on plank with output shaft
facing down. Suspended plank at far end from rafters so I had a swing
lever with motor on end.

RAFTER
|
|
|
pppppppppppppppppppppM
                                      |
                                      |
                                     T


 Attached suction cup style valve grinding tool to motor shaft.
Mounted assembly over car with head off, valve seats upwards. Apply
copious grinding paste, attach tool to valve face with suction cup.
Leave turning. Come back N hours later and check.

The fact that valve seat would widen (and needed to) was accepted.

Original valve was V'd in across face severely so there was a notch
well up into the thicker stem section. Immensely "burned". I probably
still have it here "somewhere". Must have obtained a "new" valve from
somewhere.
Car was sold in good enough working order when we left Hamilton some
years later. Shame.



    Russell
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