I'm going cross-eyed searching for an answer. I have a 1955 1st series 3100 235ci that I'm replacing the clutch in. Now, I see that the flywheel is scorched and slightly cracked. It has 139 teeth. The truck was converted to 12v and has the 6v starter. The diaphram clutch I removed is 10.5". I plan to convert to a T5. I can't seem to find the clutch kit or the right flywheel. Does anyone have some interchanges or supplier suggestions? Thanks for the help.
Flywheels can be resurfaced if not severely cracked. Flywheels with 139 teeth are made for 6 volt starters. A 6 volt starter motor is a torque motor and operates by current and will work okay on 12 volts.
From Chevrolet Master Parts List (1929-1957): Original clutch disc is 10 inch 3836119 for woven material. Then in 1957 the 10 inch disc 3836097 for molded material Pressure plate 3704776 Clutch cover with diaphragm springs 3836716 If I did this correctly, your FLAPS should be able to cross these GM part numbers over to what they sell. If they don't know or cannot help, find a better supplier.
The diameter of a pressure plate is by design larger than the clutch disc.
I'm not much help on T5 at the moment.
Attached is a 1956 Service Bulletin which also includes trucks. Maybe the pictures are helpful.
"Adding CFM to a truck will only help at engine speeds you don't want to use." "I found there was nothing to gain beyond 400 CFM."
Hey Buoymaker. Thank you for you thorough reply. The question is how "severely cracked" my flywheel is? I don't have much experience with them, but the cracks seem to be multiple hairline spiderweb pattern. Here's a picture (I hope).
Hey Buoymaker. Thank you for you thorough reply. The question is how "severely cracked" my flywheel is? I don't have much experience with them, but the cracks seem to be multiple hairline spiderweb pattern. Here's a picture (I hope).
That flywheel is bad. Don't throw it away if the starter engagement teeth are good. That ring can be removed by simply applying heat to the ring which will cause it to expand and come right off. I would leave the ring on for now so that when it is ever needed, you will be able to tell what flywheel it is from.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
Reach out to our resident T-5 guru Lugnutz. He can answer all your questions.
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
I used an 11 inch flywheel that came from a totalled 1954 Corvette. We think the owner of the Vette may have used a truck or bus flywheel, but he was no longer around to tell his story after the wreck. I used an 11 inch pressure plate (common and easy to find) and the 11 inch clutch disc originally designed for a Chevy van that came with a T5. Those are not so easy to find. I didn't know it at the time, but you can use the input shaft for a Jeep T5 to get spline spacing that will offer more clutch disc options for you. As you've already heard, that flywheel isn't so good. It is possible it can be resurfaced and if you're driving normally (not racing nor spinning your engine at crazy rpms) it may work. Take it to a reliable machine shop and follow their advice. If it is too bad, they won't resurface it. No matter what, you will have to keep oil off of it to help keep it from burning again. Also...you will probably need the short throwout bearing with the T5. At least I did and I also had to make a new clutch connecting rod as the original one just didn't allow for enough adjustment. Image of old and new below. You can't buy a new flywheel (at least to my knowledge), but you can find used ones. Good luck!
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
Reach out to our resident T-5 guru Lugnutz. He can answer all your questions.
Except maybe I can’t. I’ve no experience swapping flywheels in these older trucks. A 10” clutch disc will work just fine with a 235 engine. I know the 1960-66 trucks had mostly 168 tooth flywheels but not all will accommodate an 11” clutch disc. I took this picture to help you see the differences at a glance. Both flywheels are 168 tooth.
If you have nothing better to do, come sort through the pile of flywheels at a local salvage yard 40 minutes west of Columbia, SC. Haha!
West coast. It would be fortunate to find a good used one locally. The only person I know on the west coast is (http://www.jjinlines.com). He is a performance engine builder. He buys engines to rebuild and sells off parts that he doesn't need. Also sells on ebay.
Be sure to check the clutch disc for evidence of heat damage due to oil leaks. You want to remedy oil leaking on the clutch before buying new parts. Valve cover and side cover but also 2 small expansion plugs on the back of the engine. Sometimes coolant can leak from the backside at the casting opening seals. Picture can be provided if needed.
"Adding CFM to a truck will only help at engine speeds you don't want to use." "I found there was nothing to gain beyond 400 CFM."
Buoymaker, 52Carl, JonG, BC59, Justhorsenround, and of course Lugnutz... thank you all. I've used all your helpful feedback AND talked to a clutch shop that Lugnutz referred, who specializes in our old trucks. All my parts are ordered and on the way. I'll follow up next week after they arrive. Thanks again. Donbolt
Hi folks. After digesting the input and considering the alternatives, I got my 139 tooth stock 1955e 235 flywheel resurfaced locally. It turned out great and all that can be seen are two very fine, very shallow hairline cracks. I've been coached not to worry about those for normal (non-race) driving I will do. Along with the resurfacing, I had the ring gear flipped. It cost me $50. Notice that 139 teeth are 4 per inch.
Follow up: I got my stock 1955.1 235ci 139 tooth flywheel resurfaced and the ring gear flipped at a local machine shop for $50 total. It came out great with only 2 very fine hairline cracks. I bought new 10.5" clutch, pressure plate (raised diaphragm), throw out bearing (short), and pilot bushing (not bearing).
Side note: Of 3 rear main seals, I got the Best Gasket #4519s to work with engine in the truck. The Best Gasket #6100 rope and the Fel-pro bs5048 rope both failed to work/tore apart with a Lisle Sneaky Pete and help turning the crankshaft. Removing the clutch and flywheel and lowering the main caps helped along with a vigorous, practiced technique I'll share in another post. BTW, Best Gasket tech line says not to use the 4519s on any trucks older than 1956, despite parts dealers' claims. It worked for me. Time will tell.
