Tappets .

[tdc]

Having just completed a top end overhaul on a new to me 1978 Lightning I can see that one exhaust tappet is by no means central to the valve stem everything seems straight the washers and springs are in the right place. I did read in an old tuning book that you have to ensure that the rocker arms are central to the valves stems but sadly it did not state how to achieve this. All I can think is the rocker arm is at fault ?

[Allan G]

Do you mean 1968as the factory went bust in 73'.

Assort the spring washer location so that the rockers align as close to centre as possible. That's what I do, I'd rather have them central than not.

[tdc]

Yes 1968 .Thinking about it it could be the valve guide angle I could remove the Thackery washer leave the thrust washer and make up a distance piece in Phosphor bronze to centralize the tappet I cannot see how else the rocker arm position could be adjusted !

[Mark Cook]

Slightly off center helps the valve to rotate.
This action distributes the ware and lengthens the life span.

Mark

[Allan G]

Slightly off center helps the valve to rotate.
This action distributes the ware and lengthens the life span.

Mark

Learn something every day Mark. Thankyou.