I am thinking of changing around my cooling system.I have a 54 panel with a 351 w it has an original radator that was recor.It has a trans cooler and ac condensor.Most of the time it runs cool.But on days when it gets up in the 90s the temp will rise to about 220.It has a 16 in electric fan mounted to the rad.with the originanl shroud around it,and is controled by a theromstat.I am wondering if I moved the trans cooler between the frame rails if this would let more air through and keep it cool.And would I need a fan on the trans cooler.I talked to a guy that has done this without a problem.What do you think?

 

You can move the trans cooler under the truck as along as air can circulate all around it and you don't need a fan on it. My 48 has such an arrangement and I've run trans coolers like that for years. However, I don't think 220 is too high for ambient temps in the 90s either. There are thermostatic switches available you can use to get your electric fan to kick in at 190 or 200 if you don't like seeing 220 on the gauge.

 

You say you have an electric fan mounted to the inside of the radiator, and the stock fan shroud still attached to the rad? And you do not have the stock, mechanical fan sitll on the front of the engine? I don't think that is the most efficient way to move air through your radiator. If you aren't using the stock fan, I would not have the stock shroud installed. The stock fan and shroud is a matched pair, where the shroud helps the fan pull air through the entire radiator. Without anything to pull air out of the shroud cavity, it is blocking air flow by forcing the air moving through the rad to be effectively pushed backwards through a funnel. I would remove the shroud and see what happens with your temp before relocating other items. Or put the stock fan back on.

 

because of the hight of the 351w motor the fan is to low and only covers 1/2 of the rad thats why I went to the electric,I will try takening the shroud off as that would be the easy way.My thought on moving the trans cooler is with trans cooler,and ac condenser in front of rad they block to much air flow.

 

220 won't hurt it. Actually it ought to be running a 195* thermostat and that extra 25 degrees is only a 10% increase - which as you said is worse case anyway. If it gets higher than that - like passing 235, then I'd start to worry.

 

Trans coolers are typically very small compared to the size of a radiator, so it shouldn't be an issue. Lots of vehicles run trans and engine oil coolers, a/c condensers, etc., without issue. You still have the a/c condenser there, and it is larger and dissipates more heat than the trans cooler does.

After you get aboue 35mph, normal air flow outpaces what the fan will pull, anyway. It's my opinion that you have hot air cavitating inside the shroud area, and your cooling system isn't as effective as it could be. I would definitely try taking the shroud off and see what happens. Good luck.

 

I know I wouldn't want to see 220.

 

I'm with you. I know 220 doesn't hurt anything...but I still rather see 180 on the gauge.

 

Definitely remove the shroud. Make sure you have all the rubber air seals in place: the one at the bottom of the grill opening called the gravel pan to radiator seal and the one between the latch plate and hood are critical. Is your fan mounted to the rear of the radiator so it pulls air? Are you running a thermostat? Have you installed a hi flow water pump? Sometimes pushing the water too fast thru the cooling system can cause high temps rather than help, Chevy SBs are noted for that issue. You have a tranny cooler mounted in front of the radiator? Do you not have the tranny water cooled? Only air cooling the tranny is asking for serious problems! An automatic tranny is designed to operate within a small (engine temp) range, air cooling it has no temp control or moderating characteristics so is going to fluctuate all over the board. A transmission temp gauge will tell you if you need an aux cooler. It's not good to overcool the tranny in trying to cool the engine, then you're making a second problem. The AC condensor should be mounted as close as possible to the radiator core, often tie wrapped right against it.
If the cooling system can handle 220 without boiling over, then it's not a problem.

 

My recommendations would be remove the Original Shroud, relocate the Tranny Cooler, and burb any air pockets that possibly are in the cooling system. I would also try another temp gage and sensor to insure the first one was accurate. Goodluck
Brad

 

I have the seals in place the fan is behind rad pulling.state is a 180 water pump is stock,not high flow,Fan has a control on it,As far as the cooler goes,the original fordomatic didn't have a water cool option as it just had a large heat sink on the side.If I put a trans temp gauge on what temp range should it run in?Then would I be father ahead with a new rad with trans cooler built in,and where should i get it.

 

You do not need a new radiator with a built-in transmission cooler. I respectfully disagree with AX on this point and I think we have had this discussion before. I have been running air-cooled only transmission coolers since the 70s and I have yet to have a transmission fail because I did not use a radiator cooler. If anything a transmission cooler may unnecessarily heat up the water in your radiator and hurt engine cooling. It doesn't make sense to me to run 250 degree transmission fluid into 200 degree water to cool it. Over the years I have run a 700-R4, 350 Turbo, 400 turbo, and a Powerglide this way. I am currently running a 350 turbo this way in my 48 and will soon be running an AOD this way in my 49 302/AOD. You do not need a radiator transmission cooler!

 

Respectfully Vern,
you may have had success and/or dumb luck not destroying a tranny (my guess would be more of the latter, coupled a great deal with the climate where you live) but there is sound reasoning for using a radiator contained intercoolor and it isn't based on just cooling the transmission. Do you really think the automotive engineers are so dumb or hell bent on tradition or incurring extra manufacuring costs that you do not find a single air cooled only auto tranny in any production vehicle? The purpose is to allow the tranny to operate at a steady, narrow design range of temperature variation. Air cooling has no real control over the amount of cooling produced, it's dependent on environmental factors such as ambient air temp, air flow, etc. It will run significantly cooler (or sludge forming reluctant to shift cold) in the winter at high speeds (at least until it get plugged with snow and ice) and significantly hotter in the summer rush hour traffic (I wonder how long one of your trannies would hold up pulling a trailer over the winding twisty slow moving <30 mph roads in the western portion of our state in 95+ temperatures with very little air flow thru the cooler or even in the winter temps in MN or WI?) Heavy use produces much higher transmission fluid temp increase spikes than in the engine under the same conditions. You should install a transmission temperature gauge and record the readings frequently while in use over a range of weather conditions and driving speeds, you just might change your mind. Anecdotal evidence is not sound reasoning. Just because you have not (yet) had an accident while driving and talking on a cell phone is not compelling evidence that it is safe or even sensible for everyone to use a cell phone while driving.

 

Ax, you may be right about the dumb luck. I have nothing but 40 years of experience to back up my claims. Most of the experience I've had was in Florida where I lived for 50 years before I moved to NH so I know something about heat. Heat is the main enemy of any automatic tranmission and 90% of all transmission failures are due to excessive heat. The ideal operating temperature of an automatic transmission is around 175 degrees or less. You're not going to get there with a radiator cooler. If fluid temperature can be kept to 175 the fluid will last almost indefinitely. A rule of thumb is that for every 20 degrees above 175 fluid life is cut in half. Typically, fluid enters the radiator cooler at 300 degrees and is cooled to only to about 240 to 270 as it leaves so there is no way a radiator cooled transmission will run as cool as an air cooled one.

I have yet to hear of anyone who has ever lost a transmission because it ran too cool!

I guess we will just have to respectfully agree to disagree on this subject and hope my dumb luck continues!

P.S. I don't talk on cell phones while driving either....