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1947 Pontiac 8 cylinder valve tappet adjustment

Old 30's/40's Mopar Nut

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Hi, I recently installed a rebuilt motor in my car. runs nicely, but has a noisy tappet.

Looks to me that the manifold should come off to do the job accurately?

I know they should be done hot. I have old chrysler products and have set them running with a go-no-go feeler.

You  can remove the inner fender wall to do the job. Smart! No such luck with the Pontiac.

Any tips or suggestions?



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Well on my 1936 6cyl (and sixes and eights are the same engine family in Pontiacs), there was a piece of the top of the fender to remove to get access. The access was still horrible. I tried to do it hot, tried to recheck it hot, and it just wasnt working out for me. The exhaust was really in the way in the middle, and I had one real clanker right in the middle.


I had to do it cold. I probably added .001 or .002, but maybe for an engine as new as yours you could find hot and cold settings. I had the plugs out to make it easy to turn, and I went around in the firing order with feeler gauges using the go-nogo method. I did not try to cheat with only 4 crank positions or anything like that, I just followed the distributor rotor to the next firing cylinder and did intake and exhaust. Then I went around AGAIN and rechecked them all with an offset foot on a dial indicator. That was to compensate for any wear pounded into the adjuster by the valve stem. I might have redone 2 of them or so, a slight change. They are pretty quiet, especially hot, but you can hear them if you listen close, and they all sound alike.


Taking the manifolds off would have made it MUCH easier. I didn't. Also, the Pontiac tappets take one more wrench and one more hand compared to Mopar. It's a bit like juggling cats. Have fun!

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