Having a lot of trouble finding a complete distributor for our old 1959 GMC 100 that has the larger 270 six cylinder engine. The distributor for the more common 235 engine won't fit. Really could use some knowledgeable guidance.
Gramps, hope you don't mind I added your truck picture. I thought it was such a neat one with the covered bridge. Some "knowledgeable guidance" will not come from me. Stand by. The gang should be in shortly.
~ Peggy M 1949 Chevrolet 3804 "Charlie" - The Stovebolt Flagship In the Gallery || In the Gallery Forum "I didn't see this one coming. I don't see much of anything coming. :-O"
The distributor for the more common 235 engine won't fit.
Is the problem actually with the distributor, or the vacuum advance unit? I have a couple of 270s with distributors, and a 228. I'll do a comparison and see if I can figure out if there's any way to adapt a Chevy unit to the GMC engine. What kind of problem does your current distributor have? They're very easy to rebuild.
Once you make a couple more posts and get past "moderated" status, post a few pictures of what you have now, including the part number and serial number. Good luck! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
I agree with Jerry that the Chevy distributor should fit. What does not fit? I have a '54 or later Chevy distributor in my '52 GMC 228. I've had my original 228 GMC distributor in a '57 GMC 270. I'm not saying the advance curves are the same or the gear material is compatible, but nothing kept me from plugging them in.
All 1955.2 thru 1960 248, 270 and 302 cubic inch GMC engines used the same distributor, part # 1112414. I don't have parts documentation for '54 through 1st series 55 GMC or any Chevy documentation. Prior to '54 the distributor was noticeably shorter, especially from the cap up.
Googling "distributor 1112414" turns up a BUNCH (that a big bunch) of distributors that the sellers say are for a '54-62 Chevy 235 and GMC engines.
Last edited by Bill Hanlon; 06/04/20243:31 AM. Reason: typos
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
Gramps if you want an HEI distributor, you can see how I have converted these to fit the 235. Please go to page 3 below and then look for a post titled "New HEI distributor for Stovebolt for <$100" or something like that. It should fit. It is not original and it is ugly but these work well on the inline sixes once you get them modified. Good luck.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
... and once you get a distributor mounted, MAKE SURE it is seated all the way in. I have a story about a hot-rodded 270 that a shop who wasn't familiar with our inline sixes that ran for about 5 hours with the distributor not plugged all the way into the oil pump. It finally worked its way out enough to disengage from the oil pump, but still was engaged with the drive gear on the cam. The engine seized.
A friend and I tore it down and found the following:
I did not duplicate the “No oil pressure suddenly after 5 hours of run time” problem. It appears that the distributor was not properly installed and “rode up” over time until it was high enough that the tang on the end of the distributor shaft no longer engaged the slot in the oil pump shaft. The distributor was out of the engine when we picked it up so we cannot be sure this is what happened, but witness marks on the end of the distributor shaft support this theory. We used air pressure to test for gross leakage and when we found none we used a ½” drill motor and a homemade shaft to turn the oil pump. Oil pressure reached 57 PSI at an estimated 600 RPM (1200 crankshaft RPM) and stayed there (being regulated by the oil pumps over-pressure dump valve) to the 850 RPM max of the drill motor. We found no unusual leakage pressurizing the system with either air or oil. The design of the distributor and its hold down mechanism is such that it is possible to install the distributor in the block far enough that the gear meshes with the camshaft gear, but the tang is not in the slot of the oil pump. That would allow the ignition system to work, but not the lubrication system. It is also possible to install the distributor at the proper depth, but not properly secure it in place. Over time it could work its way up in the block and eventually come clear of the oil pump (oil pressure drops to zero) while still has about another 4/10” of vertical movement before the gears don’t mesh and the distributor quits turning causing no spark and the engine dies.
Edited 6/4/24 20:00 to REMOVE A LOT OF OFF TOPIC INFO. SORRY TO REMOVE ITEM #12 WHICH HRL REFERS TO BELOW.
Last edited by Bill Hanlon; 06/05/202412:55 AM. Reason: REMOVED A LOT OF OFF TOPIC INFO
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
It's also possible to fit the GM HEI reluctor and pickup coil parts into a stock point type distributor. The installation looks completely original to the casual observer. The module has to be mounted externally, to a finned aluminum heat sink- - - -which can even be hidden under the dash, if desired. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Item #12 above is a pretty common myth- - - -since piston rings are in constant motion, rotating around the pistons in a random fashion, it's not uncommon for ring gaps to align- - - -momentarily. I have documented this, using a "training engine" with a quartz window inserted into a couple of cylinder walls to allow observation of the pistons in motion with a strobe light. At one time I had a videotape of the running engine- - - -the rings can be observed moving around the pistons in a very random manner. It's a good idea to stagger the ring gaps on assembly, but expecting them to stay that way is an impossibility.
The only exception is on a 2 stroke engine with ports in the cylinder walls. Those pistons have dowel pins in the ring grooves to prevent the rings from walking- - - -to keep the end of a ring from hanging up in an open port. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
Still haven't heard why "The distributor for the more common 235 engine won't fit."
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
1950 Chevrolet 3100 (Ol' Roy) 1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1956 Cadillac Sixty Special Fleetwood (The Godfather) | 1966 Oldsmobile Toronado (The Purple Knif) | 1966 Ford Mustang (Little Red) | 1964 Ford Galaxie 500 coupe | 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)