The straight 6 in my 1950 chevy deluxe 3spd has always run LIKE ****. Very very hard to maintain an idol, backfires, rarely starts on the 6volt power alone. yes ive gone through many batteries and generators. I just realized that it is in fact a 235 out of a 1954 chevy powerglide car. All along of course I have been buying parts for a 1950 stove bolt. Just about all external parts on the engine have been replaced with ""1950"" 235 parts. Things like the carb, fuel pump, starter+ solenoid, distributor, etc in attempt to get to the cause of the problem. Just out or curiosity I went to the parts store and discovered that as far as their books are concerned the distributor cap and rotor are DIFFERENT between a 1950 and 1954. Could these details be what is affecting my engine performance? Any idea how this year diff might affect the timing? Could the firing order be different? Any masters out there?
I'd bet the leaky rochester is the real problem. Upgrading to a Landon's holley/weber made mine so much smoother. the 6 volt part only matters to the starter. once running, a 12 volt swap would still be 6v at the coil. Physical timing wouldn't be off, but the increased gap of a non-matched rotor/cap COULD be a problem. I still think the 1 bbl carbis the culprit.
I know that 235 parts are all interchangeable, in fact, most will interchange with a 216, so I doubt it's the cap even though it has a different number. Caps are cheap. You could change it just to be sure.
The cap and rotor were different starting in 1953 (taller cap, other than that I don't know), but I don't know what year distributor is in your engine nearly sixty years after the fact either. The firing order, however, is the same.
****. Im guessing I also have a '54 distributer in there. Yeah I picked up the taller cap and roter today and the car might have run a little bit better, but still like total ****. Its been said before that the entire distributer is not in good shape and occasionally the vac***e advance does not do its job. I just dont feel like the worn distributer is the cause of the engine CONSISTANTLY running like horrid ****. Any other ideas guys?
I also have a 1950 that HAD a 216 in it. I ran a bit like yours. The valves were pretty crudded up and the springs were weak from sitting a long time. It caused the valves to be slow to return to seat after coming off the high point of the cam lobe. The old guys ran Marvel Mystery Oil to cut the crud. You might want to pull the valve cover and turn the engine by hand and see what is going on. Also check for bend push rods. Mine had one. The old solid push rods were not very strong. BTW - I went to a full pressure oiling 235. It runs a LOT better.
A worn distributor will cause the points to never be gapped right, and run like horrid ****. Get a hei for a 250 or 292 and remove the little collar, and use it.
If you go 12v. later, try a Pertronix in the stock distributor. Not sure if they have them for 6v. No more points to worry about. I have found them to be reliable in our cars.
A worn distributor shaft will make it run badly as it won't keep time properly. Another suggestion is to check for vacuum leaks around the manifolds/head and the carb bases. It could be a case of remedying a number things, that right now all combine to make it run rough.
He can also drop a bottle of ATF in the tank, at the next fill-up. It'll clean out the inside of his cylinders, while the MMO cleans the all the oil related parts. Diesel fuel (in lieu of MMO) works too, but you don't run it like you do the MMO. ...also, what "Quake Monkey" said. 100%. Off hand, to me, it sounds like a vacuum leak and/or a messed up choke. 6narow
yeah i dont know how to check compression and it was done for me about a year ago i dont remember the exact numbers, but the old dude said it was pretty good and showed enough signs that the engine wasnt in need of rebuild....
My 235 ran like **** when I got it and I had 0 compression in 3 cylinders. The head gasket was burned through between 3-4 & 4-5, replaced the head gasket and adjusted the valves and it smoothed right up. compression guage is under 20 bucks I think.
It's easy. The quick and dirty way is to grind the stock locating collar off of the HEI housing and use a 216/235 clamp on style retainer to hold it in place.
The distributor has a wire that attaches to a screw and goes thru the distributor.I've found at times the insulator will crack and cause a short in the ignition system.Runs but runs like ****.Take the screw out and see what the insulator looks like.Little parts so watch what your doing.If the insulator looks bad, I've covered the screw with shrink tube.Worth a look,easy fix if thats what it is.
6 volt systems need heavier gage wires to the starter and ground. That's one thing I'd suggest looking into. Lower voltage = higher amperage, need bigger wires.
yeah, or you can buy a mini-HEI from Langdon, or just buy a new stock distributor. I got one for my wife's '51 ('60 235) from Auto Zone in about 1-2 days
i did a tech write up on installing a hei in a 235 complete with pic's last year. easy as hell and cheap. takes about a hour and bamm! 250 dizzy drops right in. the rochester carb is/was primative and the carb that langdon offers is really worth using. i keep a modified hei around just for test purposes and the results will amaze you. flushing with the marvel mystery oil is very solid advice and you can eliminate the carbon buildup on the valves by slowly feeding a quart of atf into the carb at high idle but do it at night because it will cause ****loads of smoke for a short time but works great. good luck!
Fuel pumps are different too, I have a '53 235 in 51 fleetline and it took a little while to figure out what was what. Is the heat riser and vacuum advance working? I have a langdon's Holley/Weber conversion on mine and its a good carb, simple to work on and easy to tune.
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