Valve Rocker Adjustment.

[Chazbeam]

valve adjustments change with heat

Hi Guys
i got curious with this thread because of my recent experience with my valves on my alpine.
I was having a problem keeping the car idling at temp. every time she got hot it would idle like crap and stall but cold seemed just fine.
i thought it was carbs so i rebuilt them, that did not help then i got new ones same problem. i went to a single duel barrel setup same!.
ok i said to myself this makes no sense! it must be something else fuel supply. rebuilt pump, again same.
i popped the valve cover and looked at the valves, wile hot the clearance was non existent. cold was better but it seems after it got hot the valves did not close all the way so it ran badly. with most likely bad compression.
anyway my point being it is obviously heat related and sensitive to the change in temperature. once i reset the valves at "hot" it ran absolutely great even with a low compression in number 1 cylinder. (this i suspect the valve burned some from running it with the adjustments wrong.)
after taking off the head i found the pistons oversized and head shaved witch made the valve adjustments difficult to clear the edge of the rocker arms without them hitting it so i shimmed the rocker stands and that worked great.
so anyway i think that heat expands it quite a lot more then we may think.
and remember that a small change in hight made me screw the adjustments down even more because of the fulcrum effect of the rockers.
the hight difference effects both sides of the rocker arms. so expansion over all will change the clearance significantly.

best regards
Chaz

 

[SIVAllan]

Valve Rocker Adjustment

There's an even simpler way to make the engine turn - learned it from Jim Ellis - make sure your car is on a nice flat smooth surface and simply grasp the front wheel with your hands and move the car forward until the next valve opens. You can rock the car back and forth this way very easily to adjust the valves.

Use the hand crank?

(Did all series have a hand crank?)

 

[George Farrell]

While I had my engine out to do clutch work, I decided to check my valve lifters for pitting, due to the new oil formulation. The lifters were fine but, seeing that the adjusters were way past their midpoint, I decided to shim the rocker standards. I found some .032" brass stock at my local Ace hardware and made some shims. That was the only change that might change performance, and I was surprited how much better the engine seems to run. Placebo effect?

George

 

[Series3Scott]

Use the hand crank?

(Did all series have a hand crank?)

Yes, all did, and for your Series IV it would have been clipped behind the spare wheel in your trunk.