Pictures are back, so
Have any of you GMC guys seen this spacer? Anyone seen one on a Chevy 6?
I have one on my '52 GMC 228 between the engine block and the "octane selector". None of my GMC Master Parts Books (1939-60, missing only 55.1) show this part.
The first picture is shown with the "nipple" up, but it actually installs with the nipple down which fits into a dimple on the block. The distributor shaft goes thru the big hole and the same bolt that you loosen to adjust the "octane selector" goes through the smaller hole.
The second picture is from the ’52 GMC Maintenance Manual shows it peeking out from under the octane selector.
Bill - It took a bit of digging through my resources to find info on the GMC "spacer" you're asking about. As mentioned before, Chevy didn't use that. In searching through my GMC Maintenance Manuals and Master Parts Books, the first of my resource books for that piece (actual called an "adapter") show up (I believe) in a 1939 Maintenance Manual X-3902. I again found it in a 1940 Maintenance Manual X-4044, then again in 1947 Maintenance Manuals X-4703 and X-4704. I did look at a 1955.2 Series Maintenance Manual, but that item seems to have disappeared from the diagrams/figures in that and later books as you mentioned.
Then I switched to checking GMC Master Parts Books I have or have access to. I found the "spacer", actually listed as an "Adapter, Vacuum Control" GM# 1882532 listed in a 1945 Master Parts Book X-145020. Also listed in a 1945-46 Preliminary Parts Book X-145021. From their I jumped to GMPartswiki and found GM# 1882532 listed in the GMC 1951 Master Parts Book X-151004 and again in the GMC 1964 Master Parts Book X-164001. I did lastly check my GMC Parts Illustration Book P&SM 165, finding that the piece is not displayed or listed in the exploded distributor diagram.
I've included pictures of all this info (except the P&SM pic as I ran out of space to attach) below in the hopes that it might be useful and/or of interest to fellow 'Bolters.
All this said, my apologies to "Hawkman" for taking your thread off on this tangent. Hope I didn't cause any confusion.
