The Stovebolt Site Forums The Shop Area Engine Shop Motor for my 1954 Chevy truck.

So my 235 in my 1954 Chevy truck is stuck. Before I shell out money to have it rebuilt what motor types and years will fit in my truck and still bolt into my column shift 3 speed with a whole lot of modifications?

Direct fit with no modifications would be a 54 or early 55 235 or 261. A 216 will also bolt in, with a considerable amount of power loss. Late 55 and newer 235s have a lower water pump position which makes the fan sit too low on the radiator and hit the lower radiator hose. Late model engines can be modified with a water pump relocating plate that allows the 216/early 235 water pump to be installed on them. Some later engines also need the front motor mount relocated.
Jerry

Would there be any advantages to using a 261?

Ross, Just a note that since your topic is about your engine replacement it best fits in the Engine Shop forum so it's been moved there for further discussion and help.

Only if you like more horsepower, and a lot more torque! I build long stroke 261s with almost 300 cubic inches.
Jerry

The relocation plate Jerry speaks of is made by member Pre68Dave here on this site. It is an easy mod requiring 2 drilled and tapped holes in the block, then use your rebuilt 216/235 waterpump.
I have a 57 235 in my 54 3100 using Dave's plate and have 4000 trouble-free miles on it.
Everything that bolts to the front or rear of a 216/235/261 is interchangeable. Use your current bellhousing, flywheel etc and your current harmonic balancer.
55.2 and up are 12v and use a different flywheel than your 6v 54.1 truck. The tooth count and angle of the starter gearing are different. Should you decide to convert to 12v at a later date the 6v starter does just fine on 12v.
Have fun... I did!

Ross if you can't find a 261 (not always easy and it may also need rebuilding...some parts may be more costly than for the 235...the 235 engines from 1959 forward to 1962 are nice in that GM made changes to the camshaft in 1959 (a first step toward reducing smog in bumper-to-bumper traffic) and so those produce more torque at lower rpms and have a nice smooth torque band beginning around 1600 rpm and spanning over to around 2800 rpm.

In your search consider that main bearings for the 1955 second series and earlier 235s are reported to be all but unavailable. 1956 and later main bearings are readily available. The water pump issue is solvable with parts from this site ad HRL mentioned above. 235s are good engines and will power a half ton pickup just fine. There are good ones around because people pulled them in favor of small block V8s or 261s. Expect to pay a premium for a 261.

There is a very simple modification of the 1954 / 1955 235 block that will allow the use of later model, more available main bearings. It's also possible to modify the block and crankshaft to use mains for a small block 400 Chevy V8, which are inexpensive and plentiful.
Jerry

Couldn't figure out how to send these to you hot rod so added them here. This is what I am working with.

What's the blue stuff?

That engine looks pretty repairable to me. If it doesn't have any bits and pieces sticking out of the side, a repair is probably more feasible than trying to do a swap for an engine that you don't have any idea what's been done to it in the past. Try soaking the cylinders in a 50/50 mix of acetone and automatic transmission fluid for a few days (both on the shelf at Walmart) and see if you can free it up. I like to use the chisel shaped end of a shepherd's crook wrecking bar on the flywheel ring gear teeth at the bottom of the bell housing to persuade a stuck engine to move. I've resurrected quite a few engines that way, at least enough to run a little and see if they're worth rebuilding. My email address is in my profile information- - - -sending pictures that way works well.
Jerry

The old marvel mystery oil.

Try pounding on the piston tops with a BFH and a block of hardwood while somebody else pries on the flywheel teeth. Once the pistons move even a little, you can keep rocking it back and forth - - - -rock- - - -tap- - - -rinse and repeat!

It takes less than one hour, and a simple Dremel tool to convert a 54/early 55 235 block to use the later model main bearings.
Jerry

Was the 1954 / “early” 1955 235 issued in both ‘55 First Series and ‘55 Second Series trucks?

Discussions here suggest model year 1956 was the changeover to the later 235.

The "low water pump" engines were needed in midyear 55 so the fan would clear the lower hood profile when the body style changed. If you try to put an early 55 engine in a 55 2nd. series truck, the fan would hit the hood.
Jerry

Did the rear main rope seal get changed with the mid year 235 engine?

So to confirm: The "low water pump" 235 engines were fitted in 1955 Second Series / Task Force trucks, introduced in March 1955.

The earlier "high water pump" 235s were fitted in 1955 First Series / Advance Design trucks until production ended in March 1955.

When I changed the starter in my 1955.2 3100. The date code behind it on the block had 1/7/55.

Sounds about right, i.e., about two months lead time for March 1955 introduction of 1955.2 production line.

The engine block casting date on my 1955.1 235 is 9/20/54. Truck was assembled in Van Nuys in late October 1954.

Thanks for the Info.

In the "useless trivia" category- - - - -replacement "high pump" blocks were still being made for several years after they stopped being installed in production vehicles. The 261 engine we installed in Charlie a few years ago has a high water pump mounting, but it has a 1959 casting date, and it was machined for the later model main bearings with the locator tab at the parting line between the block and cap. I had to modify the block to accept the early main bearings, or delay the project a week or more while a different set of bearings was ordered. I chose to make the older style bearings fit.
Jerry

Don't think so but I can't swear to it. It was a machining change that altered the rear main seal channel and I believe it took place for engines made in 1956 and thereafter. They didn't actually do away with the rope seal. GM still used it but the viton/neoprene/whatever rubber type seal arrived in 1956. The rope seal stopped being an acceptable product sometime in the mid 70s when they wouldn't let asbestos be used in it.

However if you want to use the rubber type seal in your engine, you can do it. First step: Very important...buy a Speedi-Sleeve number 99387. This is to restore your rear crank surface to a nice smooth and good one. If you don't do this at least have that part of your crank polished well. Otherwise you'll chew up the rubber seal quickly. Put a thin coat of Loctite Red on the crank rear piece and then install the Speedi-Sleeve carefully.

And then, all you need to do is to cut about 8 pieces of self-adhesive foil tape (the kind used in HVAC work) that are the same width of the bottom of the seal channel. Each layer of this tape will equal .004" in thickness. Apply one piece of that to the bottom of the channel of the block and trim it on each end even with the block. Install the bearing halves and set a piece of common copy paper cut 1/2 inch by about 6 inches on top of the rubber seal but not over the bearing. Just leave about 1/4" extending over the seal inside the block. Set the crank in place and see whether there is any resistance when you pull out that piece of copy paper. If not, repeat this procedure, laminating the second strip of foil in that channel and try again. If not any resistance, keep doing this until you do have some resistance. When you feel a bit of resistance (not too much) add one more strip of the self-adhesive foil and stop. That is to make up for the .004" your piece of copy paper will have added to things. Remember the number of pieces of foil you used and repeat this for the rear main bearing cap, checking the drag of the copy paper with each layer of foil. This should do as good of a job as possible.

You can see the rear part of a crank I removed from a 1956 235 a few years ago below. Good luck!

FWIW the 1955 2nd engine I have has main bearings pinned top and bottom and a low water pump. When I rebuilt it in 1973 I used the rope seal in the gasket kit. I don't recall whether there was a neoprine one. Anyhow the engine turned nicely till I installed the rope seal. Then it wouldn't budge without a large screwdriver on the flywheel that I had installed to get it to turn over. As I recall, it took a great deal of persuasion with a hammer and a piece of wooden closet rod to beat the rope into submission. I think I soaked it in oil and squeezed it in a vice to make a shape that would fit into the groove. It didn't leak for many years after that but eventually it did and I tried the one piece neoprine seal that was available at the time. It leaked. Not much but some. Later I changed clutches and main bearings and the seal, this time with the two piece neoprine seal. It leaks worse. Not a lot but enough to be annoying.