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Time to rebuild the 235 in my '57 Chevrolet. Back in the day, I would've already tossed the straight six for more muscle, but I'm keeping this car like I found it (for the most part).

Any recommendations for a rebuild kit?

Also: Have run dual Rochesters on this car for years. I'm considering upgrading to the Clifford dual Weber setup, but wow, is that pricey. For that money, I could probably get a basic fuel injection system from FAST and go that route.

Last edited by DeepSouthRick; 10/27/17 09:45 AM.
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The only person that I know that offers a kit is Patrick's Antique Trucks. Otherwise, the parts are readily available (bearings, gaskets, pistons) as well as things like fuel pumps, water pumps, starters, generators, alternators (if you have made the switch), valves, valve springs, timing gears, seals, oil pump, etc.

Cam: New blanks are getting hard to come by, but most of the better cam companies can regrind what you have. I use Schneider in Dan Diego. Excellent to work with.

Rockers: Send what you have to Rocker Arms Unlimited in California. They are the only professional rebuilders that I know of and their work is excellent.

Distributor: Have yours rebuilt. You wont believe the difference. See if you can get Jim Linder at Linder's Vintage Ignition to do it, you wont be sorry.

Oil pump pickup and hydraulic lifters are the exception here. You will have to be an ebay and swap meet hound to find a nos oil pump pickup. They have been unavailable for a lot of years now but pop up once in a blue moon. if you are unable to source a new one, clean what you have, use a caustic hot tank. I have had to do that on a few occasions. Lifters, the new manufactured lifters seem to have a real problem with collapsing. I don't know why they cant seem to get it right but at any rate, you will need to find usa made hydraulic lifters, nos GM or aftermarket, that are at lease 20 or better years old. Otherwise you run the risk pf getting your motor all redone and have to take it apart due to a collapsed lifter. I know that rocker arms unlimited can resurface solid lifters, they may rebuild hydraulic lifters so you might consider asking them.

Dual carbs: The Clifford set up is pricy but it is a really good set up. I run one on my 261 and it runs terrific.

This is my son driving my 57 down the dragstrip with the Clifford set up at this years trifive nationals in Bowling green. It was his very first trip down the drag strip in the car so was getting his sea legs. Its my actual high school car from the 70s, sits as I originally built it as a kid (took my driver's test in in in 77). 40 years no one but me drove the car. Was a very odd feeling watching my car go down the strip without me driving it, lol.

https://youtu.be/lMVz66tyrKQ


As an alternative, consider using adapters on your current 2X1 and use 1974 Pinto 32/36 mm Holly weber 5200 carbs. These are progressive two bbls and work really well on a lightly modified 235. I ran that set up on a Weiand intake for many years on a 235, and initially on the 261 that is in the car now before I installed the Clifford two years ago. Ran great (but the Clifford runs better). Just make sure you have heat to the bottom of the manifold, electric choke, and orient the carbs in the right direction (the main jets are angled and in the corner of the fuel bowl so if you install them backwards which, by the way makes setting up the linkage easier but results in the main jet being uncovered when you pull away, resulting in a bog) You can get them at Rock Auto when available and are usually fairly reasonable. The 1974 versions have threaded fuel inlets, earlier models have a pressed in brass nipple, the threaded inlet is better.

The only issue you will have to consider with the adapters and webers is the hood clearance. The 57 hood is lower then the 55-56 hood. I had to machine down the mounting pads on my weiand to get it to all fit under the hood but that set up ran way way better then when I ran duel Rochesters and Carter YF's

Just my two cents, lol.

Mike




Last edited by mdonohue05; 10/27/17 04:45 PM.
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Thanks for all the info!

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Deve Krehbiel has done an intensive 235 rebuild tutorial on his website. Lot's of good info there that may be of use to you.

http://devestechnet.com/Home/Project1959235

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Pulled the timing gear cover (and of course, the oil pan -- Chevy engineers didn't do us any favors with those bottom two bolts feeding in from inside the oil pan). Nylon cam gear was shredded. No surprise there, but when I shined a light into the bottom end... well look at that: Rebuilder's marks, labeling the piston rods.

I always suspected the engine had been rebuilt in the past -- it just ran too solid for a 60-year-old factory motor.

Next step: Pulling the valve assembly and checking for bent pushrods. If they are all fine, my plan is to replace the cam gear (aluminum, no "plastic"!) and then check engine compression.

I don't want to make work for myself by rebuilding an engine that's been already rebuilt and was running perfectly before the cam gear lost its teeth.


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Originally Posted By: DeepSouthRick

Next step: Pulling the valve assembly and checking for bent pushrods. If they are all fine, my plan is to replace the cam gear (aluminum, no "plastic"!) and then check engine compression.

I don't want to make work for myself by rebuilding an engine that's been already rebuilt and was running perfectly before the cam gear lost its teeth.


The other place that 'kits' and at very reasonable prices is Kanter. When you look that what is included in the kit it's way cheaper then the sum of the parts.

The other place that carries a surprising amount of NOS parts is Rock Auto.

It's always a good plan to "not fix what ain't broken".

Keep us posted on your findings.

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I want to thank everyone here for all the fantastic advice and the links to part sources, information, and so on.

I will certainly keep you posted as to the progress.

Fortunately, I've also got the help of a retired uncle who was a mechanic "back in the day" and worked on these engines daily at one time. He's a great resource and is also enjoying "coaching" me through this repair since his health no longer allows him to turn a wrench.



Rick

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If you pull the valve assembly, pull the pushrods, then do a compression check. You may have hit one or more of the intake valves with a piston when the fiber cam gear let go. If you are not getting compression, you likely bent an intake valve or two which will necessitate pulling the head and replacing the bent valves.

Last edited by mdonohue05; 10/30/17 03:26 PM.
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Never learn

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Na, not for sorting out whether you kissed a valve. The cam gear is shot so Pull all the plugs and run the test. If a valve is bent, the compression will bleed past the bent valve. Then you will know if you did more damage then you thought. You can also do it with a leak down tester if you have one because with the rockers off the motor, all the valves are closed.

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If you say so

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I hear you panic but with all of the rockers and push rods removed all of the valves will be closed and no cam movement is necessary. It wont matter whether the motor is on the compression stroke or not, just as long as the piston is coming up in that cylinder. All you are trying to do is sort out whether the cylinder is holding compression. A good number of years ago when I was in my late teens or very early 20s, I had a new timing gear set that was mismarked that I had installed in a brand new 235 I had just rebuilt. Fired the brand new 235 up only to have it sputter and not start. An older mechanic come over to look at it and watched the valve movement and thought it was out of sequence. Did a compression test and all the cylinders came out low, really low. He pulled the rockers and push rods and did the test over again and still low. That is how he figured out the intake valves had kissed the pistons and that something was amuck with the cam timing, either bad cam or timing gears. That being said, a leak down tester would be the better approach if you have one, I don't, so I go the old school backyard hackerwork route. Just my experience with these motors.

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If you do use a leakdown meter you will have to have each cylinder in the TDC position otherwise the air pressure from the meter will rotate the crankshaft. A leakdown meter can be easily built for under $40. I'll bet there are plans somewhere on the 'net. I know Hot Rod Magazine had plans at one time. One of my better investments.

[b][/b]


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And I keep thinking that someone else will see what happened here...

I guess not.

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Does the engine still turn over"

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Originally Posted By: panic
And I keep thinking that someone else will see what happened here...

I guess not.


Well if you see something - you could say something perhaps?

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Pull the head and take a look. If it's a valve or piston you'll be that much closer to getting it fixed. By the time you buy, build , or find a leak down tester you'd be done. What would it take from where you, 30 minutes?


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Rotating the crank and rods without the cam being in time and rotating in sequence with them can cause interference and damage to the cam itself. Many engines have notches for rod clearance made into the body of the cam for such clearance issues to prevent this(292 for instance, and the small Ford 6 engine), and those that don't still can hit the cam if its rotated so restoring the cam timing may be a first step before rotating the crank unnecessarily to prevent possible contact and damage to the cam just in case.



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If you do pull the head (the best call by the way) turn the head on its side with the intake and exhaust ports pointing up. Pour solvent or rubbing alcohol into each of the ports, one port at a time. Look in the valve side of the head and combustion chamber. If you have solvent leaking past the valves, especially the intake valves, you likely have bent the valves and will need to replace the bent valves, and have the seats and valve faces touched up. Not a terrible job. More time consuming then anything else.

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That's pretty much the plan for this weekend. smile

For what it's worth, I was very pleased to find how "clean" the engine was on the inside. No sludge or carbon build-up. The only sludge I found was a little in the lowest part of the oil pan.

This doesn't surprise me. At some point back in the day, this car was "gone through." When I swapped out the old tranny for a T5 a few years ago, I was surprised to find a near perfect flywheel. No checking, cracks, grooves, or any signs of wear at all except for a couple of nicked flywheel teeth. Clutch disk looked new; pressure plate was perfect. I replaced the throw-out bearing just 'cuz, but otherwise put everything back in place (except for the new clutch disk to match the splines on the T5).

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You might luck out here. If it is as clean as you say, and the cylinders measure out good with no taper, might just need a light hone, new rings, new cam gear and crank gear, and put it all back together. If you end up with the motor that far apart, consider having the crank snout drilled for a balancer bolt (mr. Gasket Small Block Chevy). Makes installing the balance way way easier.

Also, as you discovered, GM had an unusual set up with the timing gear cover with most of the screws on the outside but two on the inside. You can tap the front main cap for threads, and drill out the reinforced tab on the cover so that all of the bolts are from the outside. I have always done this modification (40 years). Never needed to remove the cover until two years ago when the cover started to leak. I thanked my luck stars I did it with the new motor. Made changing out the gasket much less of a headache then it could have been, i.e., did not have to remove the pan.

Also, make sure you have some sort of centering tool when you are installing the timing cover to center the seal. If its not centered, it may leak (been there done that). I made one out of an old balancer I took apart and honed the inside with a brake hone to slip over the crank snout and allow the cover seal to center on the balancer snout.

Last edited by mdonohue05; 11/02/17 05:25 PM.

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