Technical Chevy 235 Fan Blade

I am looking for a fan blade for a 235 Chevy. This is for an engine that came out of a 1960 pickup that is going into my Sedan Delivery. I bought the shortened water pump from Chevs of the 40s. I have looked around on the auction site and see a few fan blades there, but the holes for the bolts and where the pulley is pressed onto the water pump don't look right. The pics of the ones I see on the auction site looks like the center hole is a lot smaller in diameter than the pulley on the pump I have. Also, is it me, or do the bolt holes that hold the blade onto the pulley look really small? I haven't measured them yet but they look like 1/4-20s. The engine had a fan blade on it when I bought it (it was a non-running core for rebuilding) but it says FoMoCo on it, and I just don't think that is right! It wont fit the new pump anyway. Any input is appreciated! Also, if anyone has an extra blade laying around that will fit this pump, I'd be interested.....

 

The pulley is from a 216. Some of the replacements were drilled & tapped for both patterns, which you could do yourself, then a 216 fan will fit.
For the past 50 years, we simply press the late pump flange further down, shorten the shaft the correct amount, then use a pulley which aligns w/ the balancer. Of course, having piles of pulleys & fans to pick from is a bonus.

 

I knew you would probably chime in 302GMC.

So what I need is a 216 fan blade from doing a quick search and looking at a few pictures online. I have read that using a 216 fan blade on a 235 is probably not the best idea because of the RPMs of the blade due to the differences in pulley diameters. How is that going to play into what I am working with here? If it's a 216 pulley, then I shouldn't have a problem with RPM issues?You dont have anything laying around up there in Idaho in your stash, do you?

 

That's one of the situations where the "experts" had opinions, but didn't really have the actual experience. We used what we could find, and with a little common sense, put it together & it worked. If the remainder of the cooling system is clean, it will do the job.
If I was in your situation, I'd go with the small flange & a separate pulley - which belt width are you using ?

 

At this point, I was just going to go with the stock 235 harmonic balancer, whatever that belt width is. I haven't gotten that far along with this little issue yet. I am getting everything together to break the engine in on a stand and realized the Ford fan blade that came on the 235 core wasn't going to fit the water pump I purchased.

 

I'm thinking something like this may work?


1937-1955 Fan blade for engine
Fan blade for engine, 1 inch pilot with 2-1/4 inch bolt pattern, new, black, 216 L6 engine, 15-3/4 inches from tip to tip, new, fits all water pumps except WAP-3, WAP-7, WAP-8 (see U-FAN2155 in used p, works for Chevy or GMC trucks

 

That is the 49 to 54 style fan that the GM books says will work back to 37 but during production through the years there were different fans made,I have that fan on my 37 p/u that has a 57 235 with a 54 water pump and will work for your application. That fan on my truck is only 1/4 from the radiator so I had to find a correct 37 fan so I can remove the fan belt.

 

Thanks for the info Jeff. 302GMC has me hooked up with a blade that will work. Thanks for all the ***ists from everyone, especially 302GMC.

 

what fan blade did you finally use

 

@302GMC fixed me up with the blade. It's a 4 blade one. Not sure what it came off of. I still haven't gotten the engine in the car, but ran it on a test stand using the radiator and core support that I did my best to mock up to the correct dimensions.

 

Make sure it has the smaller truck balancer or it could spin that water pump too fast.

 

302GMC is right . We call that the racer fan as it was smaller and cleared the harmonic balancer. It also made a lot less noise. I made this conversion many times and it was easy as long as you went with the narrow belt pulleys.

 

Monty, what are your plans for the car and engine. If it’s cruising I would not worry about fan speed. If your going to run the engine at 4000 rpm plus for most of the time there might be some concern.

On a different engine the use of a smaller water pulley is the fix for a cooling problem that water doesn’t move thru the radiator at idle. The difference is 2” in diameter. I needed to use this fix and have for 5 years.

Most want the 3/8” pulley to use accessories on their engine. Our 302 GMC uses the 228 pump and Tom Langdon’s 292 pulley which speeds up the water pump. On the street the rpm is typically under 3000 for all driving. cooling is great with a 14” fan and a shroud.

 

It's going in a 50 Sedan Delivery, more of a cruiser than anything.

 

I had the whole center break out of mine from half a century of fatigue. A ring around the outside of the bolt holes broke in a perfect circle. Think I should sue GM?