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I have a "48" 3100 with a "55" 235. 1,000 since rebuild . The temp runs at 180 on the highway but in town will climb to 200 and higher if stop and go driving. I did not notice this in-town temp the first few hundred miles. I advanced the timing and adjusted the floats on the carbs to stop a gas leak and that is when I think it started running hot. I changed the timing back to where the ball is just in the window. This engine is so new to me it is hard to say what normal is. I have a short shaft water pump with original 4 blade fan. Space between radiator and fan is 1.25". The draft tube has been replaced with a PCV valve. Questions are:
1) If the engine was running lean causing higher temp would it also run higher on the highway.
2) Should I shim the radiator closer to the fan.
3) Could I just build a fan shroud to solve the problem.
4) Would a different fan blade help.

It's, of course, hard to say. New rebuilds sometimes run hot. Timing will cause it. Carb has no bearing really. I would like to know if anything has changed, fan distance wise, during rebuild. What did change? Was the same motor in there and was rebuilt or another motor was in there? If the engine is "new to you", I guess it's a different engine than you had before? A proper shroud will help. Is your T-Stat 160 or 180 or? Is it new? Is it working? Top rad hose not collapsing?

Question 3)Could I just build a fan shroud to solve the problem?
If you do not have the fan shroud you should find or make one. I doubt this will solve the problem completely, but it will help.

To have 1.25" fan to radiator clearance on a 48 is unheard of.
I suspect the radiator has been moved forwards.
Advancing the timing should help with cooling.
A bad vacuum advance can add to overheating.
Can you post a picture of your fan and radiator set-up?

There is a fan shroud (factory) available for the AD radiator. This came on big trucks with the HD radiator and it bolts right up to existing radiator.
http://www.flickr.com/photos/advance-design_parts_co/10039269655/
http://www.flickr.com/photos/advance-design_parts_co/10039269675/
http://www.flickr.com/photos/advance-design_parts_co/10039269755/

This is a just finished as of July this year, frame up restoration project. Less then 500 miles on the truck. The original 216 was replaced with a 235. Original radiator, all of the radiator hoses are new. It seemed to me that the engine was running hotter after I adjusted the timing but I may just be dreaming that as I have not drove this truck that much. It started pushing anti freeze out when shut off after driving around town. I am just trying to figure out if there is a problem or not. The water pump is a short shaft and the blade is new. It does not seem to have a as much pitch as the original blade but as I recall this blade was for a 235. The radiator is in the original location. This and this are pictures of the radiator showing the clearance. I have a 180 degree thermostat that is also new. The engine runs at that temp on the highway, just not in town. I am mostly wondering if I have it running hot due to running lean or is it normal to heat up driving slow around town. How can I tell if I am running lean. I looked at the spark plugs and they appeared normal. I work sheet metal for a living. Maybe I will make a shroud and try that.

As you say, that blade does not have much pitch. It looks like a lot less pitch than what I'm running. Seems like that could be enough to cause overheating at idle or slow speed. You might try your old blade and see if there is a difference.

Dennis

After overflow, after it cools, look in radiator and see if water is covering fins/tubes. If it is, DON'T add water. There has to be room for expansion in a open system. 200 DEG would be OK if it was max. Try pulling over and running at high idle to see if it cools down on gauge...and I repeat, a shroud will make a big difference. It ain't that hot in NE? If that fan pitch is stock I would be surprised. Looks like it would do nothing, which it is. Wouldn't a 160 T-stat be a cheap/easy test? I would do that for sure. Go with more flow baby.

I'm running a 160 thermostat and my old 216 stays under 180 in all driving/idleing conditions. I also leave approx1 1/2 - 2" of air space in the radiator.

I just recently got the heater operational and even tho my tests was when ambient temps were around 70, the heater ran me out of the cab. As been said you might try a 160 thermostat to see if that lowers your temps.
Good luck
Dave

If I understand you correctly, you have a short shaft water pump on your 235, therefore, your fan will ride lower on the radiator. My COE has the same setup and overheats at parade (walking) speed and does just fine at all other times. I don't think you get efficient cooling at very low speeds.

I would be concerned that a shroud won't fit with the low set fan. Pre '68 Dave above may have the solution with his adapter plate that centers a 216 water pump to the radiator when attached to a later 235.

Kent

I wondered about the short shaft water pump and the fact that it is not centered on the radiator. The reason I went with it over the adaptor plate was that I had not read about anyone with complaints that it did not cool properly. I am going to try the old blade that appears to have more pitch. If that does not solve my problem I will make a shroud that will get the fan pulling thru the entire radiator.

There are a couple of questions I have.
First, what balancer are you running? If it ia a 1955-62 pass balancer it is not recommended to run the small 216 style pulley on that pump. Most use a 292 Ford pulley.
Second is about the fan. You said it is new, what was it sold to fit? From the picture it does not look quite like a stock 216 fan. The size and pitch looks wrong. What is the size of the fan?

As far as overheating problems with a short shaft set-up, there are many who will say it works fine for them... but I have sure sold a lot of them to people who tried the short shaft first only to end up with overheating problems, then switched to my adapter.
I have sold over 1000 of these with no over heating complaints, even running AC in desert climates.

The balancer came from the 216 engine. The short shaft pump is from Jim Carter and has the correct pulley for this set up. The fan blade also came from Jim Carter, part # MEE243, said to be for a 216 engine but was in there section (216 to 235 swap parts). It is 15". I thought I was using the correct blade.
I wish now that I had used the adaptor plate. Is that plate an easy install now that the engine is installed and the front grill on the vehicle. Does removing the radiator give enough room to drill the holes needed for install. I am not opposed to spending the money needed to update to a better cooling system.

In theory your set-up should work except for very hot days.
I wonder now if your radiator is partly plugged.
This may not have shown up with your 216 but with a tight new 235 which generates more heat it has become a problem.
A few more miles may stop the problem.

It would have been much easier to install my adapter with the engine out but it can be done in the truck.
Yes without the radiator.

I had same problem with my 46, picked up an electric fan pushing out front and problem solved.