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HEI shaft play

4K views 6 replies 5 participants last post by  GSXMEN 
#1 ·
Okay, well I finally rustled up an old pontiac HEI, and now what I'm wondering is this: I got it all cleaned up and such, and there's little to no play in the shaft back and forth (if you know what I mean), but there's about 1/4 of an inch travel up and down. I'm assuming this is okay considering that the top part of the shaft is pressed on and that the gear is of course pinned in place, so I don't really know how it could loosen up. There is a thrust type washer in between the gear and housing, so maybe I don't have anything to work about, hope you guys can help. Thanks.
 
#2 ·
If I remember right, a company makes washers of various thickness to reduce the up and down play, I believe it`s moroso, but what I usually do is keep a few spare HEI`s and use the washers off them, in a crutch we`ve even used plastic washers. since the gear rides on the cam, there`s nothing to keep the shaft from moving up and down so it causes "spark scatter" or it`s causing the spark to occur sooner or later than it should. Shim the distributor so that there is little play and it`s set.
 
#3 ·
There is a published up and down play in GM HEI distributors and I think it is 15 to 30 thousands, not 1/4 inch!! I'll try to find it, but the fix is shimming. The reason for keeping it down is for better oil pump and gear engagement. If you have 1/4 in motion, you have almost no oil pump engagement!!! And if you think about what happens when you drop a distributor in, you will understand how much your timing would change with 1/4 in movement up and down when the engine is changing RPM.

Trees
 
#6 ·
Okay, back from spring break, and back to my computer. I looked at the gear shim set, and even with all the shims that only comes to a total of .090", whereas I need closer to .250" shimming total! Would there be any problem in running a couple thick regular flat washers in between the two .020" shims, so as to attain the desired .015" play, and keep from having to buy three sets of these shims?
 
#7 ·
Gotta admit, something sounds odd with that much free play.:confused: I can't recall ever seeing more than HALF that amount of clearance.

I wouldn't suggest using anything BUT hardened washers....even if that means 3 kits.

**If you don't mind a suggestion, I'd send an old points dist. out to have it converted to electronic. I HIGHLY recommend Dave's Small Body Heis!!:thumbup: :cool: He can be contacted at sparkman451@earthlink.net - let him know I sent ya.

I've personally seen his work and been to his shop......the quality of his conversions are second to none!!! You'd be hard pressed to beat the price too.:thumbup: He gets $135 for the elec. conv. using MSD internals and the plug-in for an MSD box or comparible. He also offers a stand-alone small body HEI for $175

Check out this thread for some pics of a Buick Nailhead dist. with Dave's conversion. Also, several positive comments from customers.
 
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