<VV> 140 Engine: Dropped Valve Seat or ? ? ?
Hugo Miller
Hugo at aruncoaches.co.uk
Tue Sep 12 04:23:59 EDT 2017
#### It's almost certainly a valve seat that has partially re-inserted
itself. Nothing unusual in my experience (which is with motors in general,
not 'Vairs I should add). It can't have gone all the way home or the valve
clearance would be back to something like normal.
-----Original Message-----
From: Jim via VirtualVairs
Sent: Monday, September 11, 2017 11:37 PM
To: Virtual Vairs
Subject: 140 Engine: Dropped Valve Seat or ? ? ?
June, 1995
I bought a '65 Corsa in 1995 to use as a spring, summer, and fall commuter.
It was in decent shape, but not worth restoring without spending a lot of
money on rust repairs. About a month after buying it, I was synchronizing
the carbs when it suddenly started running roughly. I noticed the choke
pull-off on the passenger side head was "fluttering." When I went to turn
the car off, I noticed the vacuum gauge fluttering also. I suspected a
dropped valve seat. After I took off the head, there was the seat dangling
on the neck of the #5 exhaust valve. Fortunately, no damage occurred. I
took the head in to a shop experienced with aluminum heads [Porsche & VW],
and they replaced the seat as well as the valves and springs which I had
delivered to them from Clark's. I dimpled the aluminum evenly around each
seat before reinstalling it hoping to prevent it from reoccurring.
August, 2017
After driving the car for 22 years and 90,000 miles without any major
problems, it started to "act up" again. I was leaving a suburban plaza and
accelerating up to the 40 MPH speed limit when the engine suddenly started
running roughly. I thought it might be the ignition system. After arriving
home, I shut it off and looked over the plug wires, distributor cap, and
rotor. I didn't see anything. and didn't do anything else to it that day.
The next morning, I started it, and it ran normally, so I started to drive
around my neighborhood. After a few miles, the missing returned, so I
returned home. Leaving the engine idling, I looked it over and saw the
passenger side carb choke pull-off fluttering. I thought, "Here we go
again." I shut off the car and let it sit. I was busy with my Lakewood and
didn't want to do more than one project at a time.
A few days later, I took off the valve cover on that side and turned the
engine over by hand as if doing the cold valve adjustment. I discovered
that #3 exhaust rocker arm was loose and the valve spring appeared to be
partially compressed. A few weeks later I needed to move the Corsa so I
could get my Lakewood out. The Corsa started and ran normally with the
exception of the tapping from the loose rocker arm. I ran it for 10 minutes
at 1000 RPM fast idle and then dropped it to idle for another 5 minutes. No
problem except for the rocker arm tapping.
Does anyone have any suggestions for other things I can check that could
cause this problem? I don't understand how a seat could re-insert itself.
Could the valve be sticking in the guide? Can anything be done about it
other than taking off the head?
Any ideas would be appreciated. I know I've had my money's worth and then
some from the car, but it's such a great driver that I'm somewhat sad at
having to give it up.
Jim Bartasevich
I have more respect for the fellow with a single idea who gets there than
for one with a thousand ideas who does nothing. - Thomas Edison
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