Technical 1962 Chevrolet 235 water pump conversion

I think this is a over talked subject but how hard is the 235 water pump conversion for installing a late model 235 in place of a 216. I have been reading around and found some people have had the blocks crack in the places where the block is drilled for the adapter plate? And is a hammer and a block of wood the way the harmonic balancer is installed?

 

I have the 216 water pump conversion on my 261. It is not difficult I have had no issues with cracking.
The end of the crank can be drilled and tapped for the use of a Big Block Chevy harmonic balancer bolt.
This allows the use of a harmonic balancer installer.

My 261-

 

Have been shortening '55 up pumps for 50 years - no problems. No "special" parts needed. The balancer is driven onto the shaft after bolting the 2 halves together for installation.

 

What do you do about the fan since the 55 and up one is bigger than the 54 and back fan.

 

What size belt are you running?

 

You can buy the adapter and run the earlier pump and adapter plate. Never heard of cracking issues.

Or run or make your own shorted water pump

And there is the older wide belt and newer skinny belt to keep in mind when sourcing pulleys

Seems a short sbc water pump pulley is the one used with the shortened pumps.

Drill and tap your crank for a sbc crank bolt and use an installer or else it’s a block of wood and a multi-angle swing press for installation of the balancer.

I have seen both fans used and also aftermarket fans. All depends on how much space you have, as some people have a bit of space left and some not so much

 

The normal stock belt 3/8 or 1/2 inch I don't remember the size right off the top of my head.

 

Only asking belt width as you want to keep that in mind if you do decided to go with a shortened water pump to match the pulley accordingly

 

Use a smaller 216 fan. Never kept the 5/8'' belt, always used 3/8'' for ease of finding pump pulley & belt.

 

So did you redrill the 216 fan to fit?

 

When you did the conversion did you use gaskets or silicone sealer?

 

That's all there is to it ...

 

Leaving the pump in the newer location doesn't that put the fan towards the bottom of the radiator,I'm guessing it works ok.

 

Ok so I decided to go with the 216 water pump conversion. The upper radiator hose is no problem but since its 1-1/4 straight radiator hose. The lower hose is 1-1/2 with a metal elbow. Has anyone used a stainless steel elbow in its place of the mild steel elbow?

 

I just drilled my second crank (two different motors) for a half inch bolt. You'll end up using a 29/64" drill bit and 1/2-20 tap. Use a sharpie and mark 1.5" from the tip of your drill bits and constantly watch both the top and side of the crank to make sure your keeping the drill straight. Theres already a 1/4" pilot hole in the end of 235 cranks.