VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 1935 Chevy Std operating tempeature

I have fought a 'warm' temperature battle on my '35 Std. coupe
for the forty years I have owned it! So far, I have had the radiator recored with a "high efficiency' core, replaced the
water pump baffle plate, made up a coolant recovery system, checked
ignition timing countless times, and started draining the anti-freeze and running plain water with a rust inhibitor. I
even bought and installed an accessory temp gauge so I could
watch the temp! All these things helped a little, but, today
I feel I have achieved the breakthrough! Studying my Chevrolet
Parts Book, I discovered that a truck fan blade will fit the
car even though it is one inch longer. The Book says it works
'for greater cooling!' The G M Part No is 837448, and will fit
passenger cars 1933-1936. I found a NOS fan blade and installed it two days ago. I drove the car today, Temperature
was in the low 80's, and I just went around the neighborhood
at low speeds, 25-35 MPH, with plenty of stops and idling! The
temp gauge throughout the drive was 20 degrees below what it
used to run under similar conditions! At idle, it would come up to 170 deg, and while in motion it would stay at 160 deg.
Before replacing the fan blades, running the same route, the temp would have been around 190 degrees under the same conditions!. The truck blades are a little wider, and have a
slightly different pitch. With the hood raised and the engine
running, the difference in air-flow is readily apparent! I could not believe the difference! My guess is the truck blades
move 20-25% more air through the radiator! And, it was easier and less expensive than installing an electric fan, and, for
the purists out there, it still appears stock! Only your hairdresser will know! I have pictures of the fan blades, but
I don't know how to post them! Look for the pics a little later!

Great to hear Phil. I guess the backing plate worked well for you. Enjoy!

Hi there Phil,
That is a wonderful result after so many disappointments.
I too have been through the mill with the same problem.

That is a great idea using the truck fan blade, I wonder where I could find one?

I am trying another modification at the moment, that is having proper seals machined into my water pump, both sides if possible.
The job is at my local machine shop and I await the result.
If effective, it will banish the leaking water problem all the time when motoring and will then mean that the recovery tank might even work.

Peter

An untried idea I think would work is to increase the pitch of the blades so they moved more air.
Tony

I considered that for a little while, but ruled it out because
I was afraid of putting the fan blade out of balance, creating
a vibration and shortening the life of the water pump, and
possibly destroying the radiator! My hope is that someone
will begin reproducing the truck blade! There are enough of us
owners out there with temperature issues and this is such a
cost effective fix, I think it would be worthwhile!

After a spat of talk in various posts over the last couple of years on chat. I posted that I had used a 7 blade fan off a 60's Chrysler product NON Clutch fan and that solved the problem of my 35 Chevrolet coupe overheating.

You could place a cloth diaper in front of the grill and AT IDLE that fan would draw the diaper right too the grill and hold it there. A stock flex fan from a speed shop barely made the cloth wave. That post led Phil to start investigating fan blades and pitches . After a lot of trail and machining of parts for various tests he has come up with the solution of the truck fan.

Bravo Phil !!!!!!!!!!

mike lynch

To do that, one of the problems is the pitch, if too far back would hit the fan belt. The fan would have to have spacers constructed to move the fan closer to the rad core .

Like Phil says modifying a fan blade is dangerous, as you will throw the fan out of balance putting stress on the water pump bearings and the bolts holding it .

mike lynch

A picture of Phil's 2 different fan blades. The fan blade on the left is the original passenger car. The fan blade on the right is the truck blade.

dtm

I added two washers behind the truck fan. I also found upon inspection that my generator bracket that bolts to the block were not only loose but the holes had elongated allowing the generator to move forward. Making the pulley sit closer to the fan.
So eyeball the fan belt to be sure your bracket is not worn.

Mike
I did say "untried" and that is 1 of the reasons, another is that the age of the metal it may not reshape successfully if adjusted a large amount.
Tony

Be interesting to mount the fans on a mechanism and spin the fans at a specified RPM and record the air draw thru a device.

The air draw power is whats important , to have sufficient air draw to draw the heat out of the motor coolant.

My own accidental discovery of the cloth diaper being sucked towards the grill mesh on my 35 by using the 7 blade Chrysler fan was impressive at idle. That similar fan is available from vintage air in a couple of fan lengths.

But this was accomplished with a 350 V8 Chevrolet motor.

mike lynch

The temperature here today 81 deg. I just took the '35 for a
7 mile run, including a lengthy stop for a traffic light. The
guage stayed around 160-170 the entire time, but did touch 180
at the long traffic light. As soon as I got in motion again,
it came right back to 170! I am very pleased with the results,
it's about 20 degrees cooler than it was before under the same
circumstances! The car, once again, is fun to drive without
fear of overheating or cracking a cyl head!