CGT Restoration - Update

[Walde Libera]

Gents!

I rebuilt my 235 a couple years ago so I don't know if there are cooling issues yet, but here is some info I had when I installed the adapter plate, I don't remember where I got it from , but assume from the supplier of the adapter plate.

1955-62 water pump adaptation

When installing a 1955-62 235/261 full pressure engine in place of a 216 or early splash 235 engines, this one time conversion allows you to put the early style pump on the later engine.
In the past modifying the 1955-62 water pump was done but required a press to force the hub further back on the shaft, then the hardened shaft that was left protruding required being cut off. Additionally a special pulley and fan was required. After all that the pump and fan still sat 3" lower than the 216/early 235 pump that could lead to overheating and possible fan hum.
By using this adapter with a 1941-54 water pump the pump is put back in the stock location*. If you need to replace the water pump in the future you can buy an over-the-counter pump and install it without modification.

Note: I recommend using the harmonic balancer and water pump with the belt width you want from your original engine.
1941-52 ⅝" belt
1953-54 ⅜" belt
1937-40 must use one of the above

Caution: Do not use the 1955-62 balancer since the pulley is larger and will turn the pump too fast.

* Stock for 1941-54
* 1937-38 fan will be ½” back from stock.
* 1939-40 Belt and fan will be ¼” forward from stock.

[Bob Carriere]

Hi Walde.

I first tried shortening the shaft on a good 261 pump and used a shallow chromed pulley from a SB Chevy..... had to grind the body of the pump to get more clearance as the pulley was rubbing on the outlet casting. The all the fans I had.....4 blades, 5 blades and 6 blades were not fitting properly and would hit the lower pulley on the crank........or the big GM I had was hitting on the lower outlet of the rad because the fan sits so low...... besides even with the fan blade removed I still did not have sufficient rad clearance.

The other issue is that you have to discard the large elbow outlet that fits to the head of the 261....... mine was the larger model and it prevented the installation of the throttle linkage..... I reverted back to a 216 elbow from an old cab 13...... it has a special flat spot on the bottom of the elbow that is needed to fit the throttle rod behind the pump pulley.....

Reluctantly I went with the adapter and all fits well so far...... I will need to run it wirth the full engine enclosure before I know for sure if it will run hot or not!!!!!

First picture of my 261 with the original pump and 1959 GM fan......looked nice but was useless..... not enough clearance for the rad and the fan blade hit the lower outlet of the rad....

[Bob Carriere]

....after hours of fiddling with the help of Grant we finally got it to fit....

The fan blade came from a 216.....cab 13 water truck.....

Once the pump was changed I had to change the harmonic balancer ot match the pulley size and the alternator...... belt came from a tractor dealer in 7/8 size for an Allis Chalmers.......

Bob

[Phil Waterman]

Hi Bob

I'm really going to take a look at a way of confirming flow rates, there are a couple of things that I'm curious about 216 vs 235/261 pumps and the effect of the flex type radiator hose vs the smooth or formed hoses. We used use some relatively cheap flow meters on some of the big mechanical projects I did in my consulting days.

Next step is to bring the original 216 engine down from the loft of the barn so that I really can start comparing dimensions to figure out how this really should work.

Does your Pat 11 have the mini shroud meant to control the sonic boom at the tip of the fan blades? Just kidding, at max RPM the tips of the blades are only moving at Mach .2126 only sounds like they are breaking the sound barrier. But does your truck have the shroud pictured below?

[Phil Waterman]

Hi Bob

I've gone with 30W detergent oil though did add a two quarts of 20W when the oil line T broke off. I went over to running synthetic 2 cycle oil mixed with the gas when breaking in an engine a few years ago, something like the 50 to 1 ratio to start and then less as things go along. I also lube the engine parts like crazy with the gooey assembly oil. Then before fire an engine I put the block heater on it bring it up to 120F prime the oil system up to full pressure with the drill driving the oil pump. Then I turn the engine over by hand or with the starter with the drill driving the oil pump. Let it sit then do it again the next day before trying to start the engine.

[Walde Libera]

Phil
Been away playing in the snow in the Caribou, none in Vancouver. Lots of high tech talk on the old 1929 designed stove bolt. Good stuff gentlemen.
I used to rebuild Detroit's and just before I dyno'd the engines it was standard practice to pre-lube freshly rebuilt engines mostly to ensure valve trains were adequately lubricated. It takes a minute or 2 for oil to reach the valve train, if couldn't do this in the field I used the the starter with just a non-firing to spin over for a minute. Also just pouring a quart of oil along the top of the head with the valve cover off. You tend to get a bit of splash but its a good idea to observe how things are moving. I have found even the best mechanics find issues with things breaking at start up, like keepers popping out of valve stems, rockers breaking and things like that. Also at first fire up in the initial run just to observe oil pressure beginning to ooze out of the the rocker shafts. After oil pressure checks and a final check for coolant air pocket traps in the head the the cover goes back on for a warm up run, usually babied until 110F then mid-speed until the thermostat cycles, this is where leaks start to show up. Caution is to stay away from hot water blasts from vents and rad overflows, been caught a few times. Most of the time its a hose tightening, others times its a revelation in jobber rebuild quality like leaking water pump seals. So it is normal to find issues (sometimes). With the engine cooling down I spray it down a little with thinners to wash the external oil spills off. Just make note of the fumes and enclosed spaces near ignition sources. Than tested it in chassis, with no major issues, just a leaky radiator, since replaced with a good one. I painted the engine light grey, but it looks too white for my liking. Then I made a temporary driving station and drove the CGT around to my back yard, tarped it and proceeded to the next project; making a couple of CGT fuel tanks.
Walde

[Bob Carriere]

Hi Walde

You should take a look at the .....%$#@@%$... hate to say the word...."New Ford Grey" engine color..... nice mid range grey with a touch of blue tint...... looks very much like some of the old grey chev blocks..... at least to my eyes anyways....... even available at Cdn Tired!!!!

Bob