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Tappet Adjustment

  • Terry Cockerell
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30 Mar 2021 06:16 #42761 by Terry Cockerell
Replied by Terry Cockerell on topic Tappet Adjustment
Jim being a novice in the past I set all of the tappets at 0.008" following what information I had and proceeded to cover around 10,000 miles in five years. As the restoration has unfolded more time has been devoted to everything. Roger Von Bergen who has been involved with Cords since the mid 1950's advised me to increase the exhaust tappet clearance to 0.010" Looking into this I remembered all side valve engines that I had worked on in the past had a greater clearance for the exhaust valves. As the exhaust valves get hotter than the inlet valves they need a bit more space for expansion. Side valve Ford V8s are the same but with larger clearances.
I believe that the original Factory wiring diagram for the gear change system has an error. So not all Factory information was absolutely correct.
The Topic was put up for comment for the benefit of the members.
I also had to replace the exhaust valves during the rebuild.

T cockerell

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  • JIM.OBRIEN
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30 Mar 2021 02:09 #42758 by JIM.OBRIEN
Replied by JIM.OBRIEN on topic Tappet Adjustment
Terry, I would be interested in knowing why you think .008" is too tight.

I have run that clearance for years with no problems. Increasing the gap will reduce the opening of the valve and reduce the ability of the engine to breath. There is a considerable amount of engineering that goes into the valve train. The gap is one of the critical parts of the design.
Jim

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  • Terry Cockerell
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29 Mar 2021 03:59 - 29 Mar 2021 04:01 #42748 by Terry Cockerell
Tappet Adjustment was created by Terry Cockerell
Cord reference books say both tappets should be set at 0.008" cold.
A Cord specialist has suggested that the Inlet Valves be set at 0.008" and that the Exhaust Valves be set at 0.010"
Looking at various other side valve engines including the Ford V8, I am inclined to agree that 0.008" is too tight for Exhaust Valves and that it should be increased to 0.010" as suggested."
I would appreciate any further comments on this topic.

T cockerell
Last edit: 29 Mar 2021 04:01 by Terry Cockerell. Reason: Revising text.

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