46 Ford Fan Shroud ?

Aeroman99

Aeroman99

Member
Iv been reading up on ways to help my 46 run cooler during the summer days and one way was to add a fan shroud to it. Now my car does not have one and I'm wondering if the 46 Ford Tudor sedan S/D ever came with a fan shroud ? If so is there anyone that has one they would be willing to part with or is there any after market F/S available ? I don't think it would be to difficult to build one.
Any info on this would be helpful.
 
Fan shrouds are very effective if built right. You'll need to allow wiggle room for engine torque, and should consider using existing holes for mounting.

To answer the inevitable electric fan suggestions you'll get, electrics require the generators constantly providing juice, which in turn costs horsepower that produces heat. Self defeating.
 
Iv done some research on electric fans and I don't think that's the route I want to take.
I was looking on a action sight and there are 20"x3" chrome fan shrouds for a reasonable price. I need to go over to the shop and do some measuring to see if this will work for me.
 
Aero you shouldn't have any cooling problems with a 46 in Michigan. Skip in Florida modifies all old Ford pumps to pump more water which provides better cooling. The stock pumps for your engine deliver 65 gallons each in 5 minutes, the off shore replacement pumps 75 to 80 and Skips pumps with the exclusive turbine impellers do 110 gallons. Each pump is tested for at least 5 minutes on a water pump test machine for leaks and the gsllons pumped. The test results of every pump is recorded in a log book. In over 12 years no one has ever been charged for repairs if they were to malfunction. You also need a GOOD WORKING 4 LB pressure cap. On a lot of pressure caps the rubber end of the cap don't go down and seat on the wash like seat down near the bottom of the filler neck. I'm not sure if the problem is the seat location or the length of the pressure cap. I think it's the cap as I have found them in different lengths. When the cap is installed with the locking tabs lined up, when you push the cap down you should feel the spring action of the cap start about 1/8" before the underside of the top hits the very top of the filler neck. I have had to make a large washer out of heavy gasket material, clean the bottom seat good and apply a thin film of silicon glue on the seat to hold it in place like a spacer so the pressure part of the cap seals.If it don't seal you don't have a pressure cap only the top is sealing like a standard old cap. On older Fords Skips 3 lb pressure valve acts similar to a pressure cap. The radiator has about 144 tubes plus their length restricts the flow, the water backs up and comes out the overflow tube "findiung it's own level". Ths level is about a gallon short of being filled to capacity and causes the engine to run at higher temperatures then when full. With the cap or valve the water will stay full for months even in 90 plus outside temperatures. If you fix the cap and increase the water or coolant flow it should not get over 180 on the road or 190 in heavy traffic and drop back to 180 after traveling at speed in about 1 mile. If it loses water out the overflow when fixed as described there is a crack or head gasket problem allowing compression into the coolant system which makes the pressure in the system higher then the 3 or 4" lb cap or valve and opens the cap and allow water to excape. Barr's stop leak will usually seal small leaks. Make sure there are no restictors or thermostats slowing the flow of water. This may be OK in cooler weather but not over 60 degree temperatures. A peice of cardboard over the bottom third of the radiator is good in under 60 degree temps. The card board will just sit there with the incomming air holding it in place. The pressure cap or valves only purpose is to hold the coolant in the system and act as a pressure releif valve in case of an over heating problem to protect the radiator and people. Over heating causes the pressure in the system to rise. Try the cap first. G.M.
 
I found a '46 fan shroud on ebay recently. It sold for $34.00. I just checked. There are none listed now but if you save a search for one you'll get one before summer for sure. They come up for sale now and again.
 
G.M Thanks for all of the info. I just installed 160 degree thermostats in my 46. I haven't ran it sense installing them and was told my an old timer at a car show last summer that this would help cool the motor down by allowing the coolant to spend a little more time in the radiator which made sense to me. Now if I read you posting right you where saying not to use thermostats in the summer ? The last time I was able to really drive my car was at the tail end of July last summer and it was well into the 90s and driving it home one day ( about an hrs drive ) it was reading 210 tooling down the road at about 45 50 mpr and about 10 miles from home it started vapor locking and spitting and sputtering I pulled the chock out a little and was able to make it home. It had never done this before until then. Now in the spring time it would run about 160 which was fine. Sense then I installed a electric fuel pump to help with the V/L but would also like to try to keep the engine running a little cooler. I'm not sure what type the cap is or the pressure rating is on the cap but that is something I will check into. Hopefully it will be something as simple as that.
Thanks again.
 
The thermostats or restrictors or an old wife tail that doesn't solve the problem. There are NO thermostats made today for 32 to 48 Fords that leave enough water flowing through the engine with a stock radiator to cool the engine properly. Thermostats DO NOT COOL engines, only make them run hotter by reduceing the flow of water. As I described in my last post the water backs up in the top tank. The thermostats with the small openings restrict the flow so not as much water flows into the tank. It still back up and comes out the over flow until it gets down to a level it stops comming out but now it runs at elevated temperatures. There are 3 things that effect and improve cooling, the amount of water in the system, the number of gallons per minute of water flowing through the radiator and the amount of air flowing through the radiator. Improveing any one of these will improve cooling some but improveing all 3 is the optima cooling. A good example is my 39 P/U with a shrowd, Skips pumps and a large industrial 6 bladed fan. It ran like yours before the improvements. I went to the Early Ford V/8 National show in Hagerstown Md. about 7 years ago and ran the engine in the flea market at a fast idle for over 2 hours. The outside temperature was close to 100 degrees and the water temperature never got over 180 and when raced up a little the temperature came down 4 degrees. I even left it running while I went to lunch and left Ken Ct. watch it while I ate lunch. G.M.
 
I have a repop,that fits between the top of the radiator,and the sheetmetal ahead of it.Can't use it on a merc.it's near pittsburgh pa.Never used. $30,picked up
 
If you are overheating while the car is moving at 45 mph, a fan shroud will not help you. At 45 mph you do not need a fan or a shroud as enough air is directed through the radiator from the grill and the air dams in front of the radiator.

Problems at that speed are usually fixed by having a good flow of coolant through the engine. Some common causes of overheating are: plugged radiator, collapsing lower hoses, scale in the block, plugged exhaust, worn water pumps, loose belt and incorrect timing.

Before you invest in shrouds or other non stock fixes, make sure that the other items are working correctly.
 
I agree,fix all of the above first. My '46 runs 180 thermostats,1 gal Prestone green anti freeze,stock Ford water pumps has a clean radiator core and I have never overheated. This is in south Louisiana where the temp is very warm in the summer.
 
I went over to my shop and was checking out a few things on the 46 and noticed the was no spring resistance on the radiator cap at all which leads me to believe the cap is shot and could be a part of the problem. I think Ill pull the radiator out of it and take it to a radiator shop and have them clean it out for me and give it a going over just to make sure there isnt any problems there. And last I'm going to fit it with a new 6 bladed fan.
 
Aero I suggest you do one thing at a time then you know if each step makes an improvement. Start with the easy iteams, first the cap. Clean the radiator with a strong industrial detergent mixed with 20 MuleTeam Borox, rinse good and you should see an improvement. Make sure you fill the radiator up near the top of the tank. Remove the stats and the best test is in the driveway. There are to many variables when driveing. Put a large house fan right up against the grill and run the engine for at least 1/2 hour at an engine speed of about 25 MPH. You need a hand held laser pointed thermometer which can be bought from $25.00 TO $40.00. The temperatures you are interested in is on the heads right below the hoses. You need to hold the gun the same distance away (about 12 "s) and at the same angle amaining at the same spot each time. Take the temperatures on both heads every 5 minutes and write them down. The right and left sides of the engine are seperate cooling systems NOT connected to each other in the engine, the water only mixes in the top tank. Your interested in whats happening on each side not the total mix. The temperatures should run within a few degrees of each other. Also slip a 4' peice of 5/16" clear plastic hose over bottom end of the over flow tube let it loop down and come up over the bumper and back down into a container. This will recover any coolant if you lose any and if you have a compression leak you will see bubbles in the plastic tube. A small leak can be sealed with a large bottle on Barrs heavy duty stop leak. We use the type in the clear topped bottle with aluminum flakes. Over a long period of time with the high volume pumps the flakes have a cleaning action on the internal parts. Picture show the tubes and plates in my 39 that the radiator has been in at least 25 years. I noticed the red gasket down on the bottom seat of the filler neck to seal the pressure cap that was loose like yours. G.M.
 

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Aeroman99 said:
Now if I read you posting right you where saying not to use thermostats in the summer?
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I used to go through the hassel every spring of draining out and saving my coolant with the antifreeze in it, removing the upper radiator hoses, and removing the thermostats thinking that the engine would run cooler without them then go through the whole thing again in reverse in the fall. In the first place, the engine did not run any cooler once it was warmed up. In the second place, it took a lot longer to warm up to proper operating temperature as Henry designed the engine. So, I decided to skip the semi-annual rigamarole and voila my engine stayed just as cool in the summer, it warmed up to operating temperature quicker (better for the engine) and I had hot water for the heater as soon as I needed it in the fall. (Of course, I had a new stock radiator, pumps and hoses.)

The volume of water going through the thermostats is just the right amount for summer and winter driving and summer cooling is not improved by removing them in my experience and what I have studied on the subject. Remember - Henry didn't make no junk. By the time your car came along he'd been refining the design of the flathead engine for 14 years and I believe had it down pretty good. I myself have been "guilty" of trying to improve on that but have not really found any way to. A clean stock radiator, stock pumps, thermostats and hoses work as well as any of the fancy "tweeking" that anyone does IMHO, and at least Gary in La. agrees (#11).
 
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TomO said:
If you are overheating while the car is moving at 45 mph, a fan shroud will not help you. At 45 mph you do not need a fan or a shroud as enough air is directed through the radiator from the grill and the air dams in front of the radiator.

Before you invest in shrouds or other non stock fixes, make sure that the other items are working correctly.
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I totally agree. In fact, I believe that the amount of air forced through the radiator at highway speeds may even be restricted by a fan shroud because the airflow area is reduced and the fan is actually "in the way" turning slower than the air blowing through the radiator and slowing it down. If that is true, then adding blades to the fan would restict the flow even more. Think about it.

I can see where a fan shroud or more blades on the fan may seem to help at very slow speeds like in a parade but I have been in numerous parades in temperatures over 90 for an hour or more, mostly idling, and have never overheated. But, I have a new stock clean radiator, pumps, and hoses. I think that's all you really need.
 
G.M. said:
There are NO thermostats made today for 32 to 48 Fords that leave enough water flowing through the engine with a stock radiator to cool the engine properly.
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I respectfully disagree. I use stock thermostats that are still made identical to the originals available here http://macsautoparts.com/search.asp?sb=0&ls=y&camid=F30&year=1946&make=Ford&ss=thermostat&x=14&y=6 and many other places (even NAPA.) They are important for getting the engine up to proper operating temperature as quickly as possible in the summer for greater efficiency and other benefits and to get the heater putting out heat as soon as possible in the winter. I have no problems with overheating in the summer. Why some think that Henry Ford was some kind of a bumpkin that hadn't figured out how to cool the flathead engine I don't know. I have tried all of the "tricks, tweeks, and gimmicks" and have never improved on Henry's design for cooling. Leave the thermostats in summer and winter.
 
i have had he best results keeping my flatmotors at proper operating temps by having the radiators rodded out it insure there are no blockages in any of the tubes and running 160 thermostats. 1 was a 59 and then an 8BA in a 41 PU the rest were 8BAs in 50 cars. all the vehicles warmed up when stopped in traffic but cooled back down when moving at over 20 or so mph. air flow through the radiator is a critical issue in all these flatheads.
i currently have a 50 car with a 350c***y, walker radiator and walker shroud with vintage air AC and a closed cooling system. run 190 stats and with that radiator/shroud combo it will idle and run at 195 stoped in traffic for an hour during rush hour, and at highway speed on the freeway. the walker radiator and shroud made a huge positive difference in dependability and temperature stability and consinstancy.
rodding the stock radiators always made a positive difference in all the cars i delt with. don
 
I agree with Old Henry 100%. I do have a shroud on my 39 and it does not hamper cooling on the highway. I run 180* stats, stock radiator, no pressure cap.
 
I have an engine on my test stand and put a 6 blade fan on it. It is much noisier than a 4 blade so it must be moving a lot of air. Don't think I would use it in our car.
John
 
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