Over heating problem

[speedracer]

Hey guys
I took the flex fan off my Elky (350 engine dyno @400 hp it has the Edelbrock proformance package, aluminum heads/dual plane intake/proformance cam and lifters/750 holley/headers and Accel ignition.  Engine bored out 030 over with flat top pistons. Now with all that said I thought I'd install a electric fan and afterwards it was running hot around 210 degrees.  OK here's a real stupid question! Which way should the fan turn?  Is the fan suppose to blow towards the engine or the radiator?  Do I need the shroud put back on, because the electric fan has a stroud built around it.  I have tried changing the wires around to change the direction of the fan, I've turned over the fan blades to blow the other way and still no difference.  Now I forgot to say I did take out the AC unit but I forgot about the AC radiator(forgot the name of it) thats right in front of the engine radiator, would removing it make it run cooler?
I've been told those aluminum heads will crack if they get to hot!  So guys as you can tell I'm new into rodding and any advice or suggestions would greatly be appreciated!
Thanks, Johnny

[enjenjo]

Is the fan in front of the radiator or to the rear? How big is the fan? How is it controlled? Were there heating issues before you changed it? What brand is the fan? When is it heating, at idle, or going down the road? Vacuum advance, yes, no?

Normally the fan is there to assist air flow, so if in front of the radiator, it pushes, and in the rear it pulls.

[speedracer]

Is the fan in front of the radiator or to the rear? How big is the fan? How is it controlled? Were there heating issues before you changed it? What brand is the fan? When is it heating, at idle, or going down the road? Vacuum advance, yes, no?

Normally the fan is there to assist air flow, so if in front of the radiator, it pushes, and in the rear it pulls.

I installed the 20 inch electric fan (from Auto Zone, don't recall the brand) to the rear of the radiator (closest to engine) I ran a wire to the fuse box ignition spot to turn on when the key is turned to start the engine.  Its always ran around 180-190 degress with the flex fan. It seems to over heat worse at idle than running down the road.  Now vacuum advance, my speed shop that built this engine has the vacuum port on the distributor plugged.  And all the ports on the 750 are plugged except 1 and that one goes to the pcv valve on the valve cover.  They said they plugged them because of the type of cam that was installed (Edelbrock high proformance) and I don't have any sensors installed, so when you turn on the ignition the fan is on high.
I really appreciate you guys helping me on this one.  Hell I can't even figure out which way the fan should turn or the purpose, is it to cool the radiator or blowing against the engine?
Thanks, johnny

[donsrods]

Johnny:  You and I share a common problem.............we both live in Florida=HOT.

To answer your first question, there are two kinds of electric fans. Pushers and pullers. The pusher goes in front of the radiator, and the puller goes between the radiator and engine. Easy to tell if you have the right one for your application. Turn the fan on, and air should be blowing toward the engine, just as if you were going down the road and the air would be coming in the grille.

Secondly, if you are overheating at idle, but ok going down the road, it is telling you that you need more air flow. You may have a 20 inch fan, but not all fan brands are created equal. I had a very long discussion with a radiator manufacturer at Daytona last year, and he said they test all different brand fans on an ongoing basis, and the only one he has found that is close to the advertised rating is SPAL.

I have an AUtozone special on my truck and it is ok, but we just added a SPAL to my Son's '29, and that sucker flat out pushes some air!  It jumped right out of my hand. Needless to say, I'm going to a SPAL on my truck before summer, because I hate seeing that gauge head for 220 at lights.

Thirdly, did this problem not exist until you removed the old fan?  DId you make any other changes at the same time?  The fact you are not running a vacuum advance can contribute at low speeds or idle.

Finally, make sure the rest of the system is good, and that your timing is not retarded or advanced too far.

As far as a shroud, it can help to build an aluminum plate, the size of the radiator core, and cut a hole in the middle the size of your fan, so that all the air gets directed through it. I just bought an expensive aluminum radiator and fan set up for my '39, and it came with one of these installed from the manufacturer.

Lastly, run the fan off of a relay rather than straight off of the ignition switch. That way you get full power to it and max rpms out of the fan.

Don

[BFS57]

Hello;
I have to agree with Don. When I got my 32 Ford Victoria, It would over heat in Idle. (I live in Florida too) Until, I found out I had a major grounding problem. Now, I have the fan set up with a Flex-a-lite controller.
Just put the probe in the radiator, set the (or adjust) the on temp and off temp. Mine is set up with a relay, comes on at 180 and goes off at 170. I also have mine wired so after I shut my motor off, the fan runs for a little while. The difference is that when my fan wasn't properly grounded, you could hear it run but could hardly feel any air coming from it. Now, the * thing almost blows you over!! (SPAL 16" 2700 CFM) with a Griffin
Radiator. Never gets above 180 even when idling with the air on!
Bruce

[speedracer]

Johnny:  You and I share a common problem.............we both live in Florida=HOT.

To answer your first question, there are two kinds of electric fans. Pushers and pullers. The pusher goes in front of the radiator, and the puller goes between the radiator and engine. Easy to tell if you have the right one for your application. Turn the fan on, and air should be blowing toward the engine, just as if you were going down the road and the air would be coming in the grille.

Secondly, if you are overheating at idle, but ok going down the road, it is telling you that you need more air flow. You may have a 20 inch fan, but not all fan brands are created equal. I had a very long discussion with a radiator manufacturer at Daytona last year, and he said they test all different brand fans on an ongoing basis, and the only one he has found that is close to the advertised rating is SPAL.

I have an AUtozone special on my truck and it is ok, but we just added a SPAL to my Son's '29, and that sucker flat out pushes some air!  It jumped right out of my hand. Needless to say, I'm going to a SPAL on my truck before summer, because I hate seeing that gauge head for 220 at lights.

Thirdly, did this problem not exist until you removed the old fan?  DId you make any other changes at the same time?  The fact you are not running a vacuum advance can contribute at low speeds or idle.

Finally, make sure the rest of the system is good, and that your timing is not retarded or advanced too far.

As far as a shroud, it can help to build an aluminum plate, the size of the radiator core, and cut a hole in the middle the size of your fan, so that all the air gets directed through it. I just bought an expensive aluminum radiator and fan set up for my '39, and it came with one of these installed from the manufacturer.

Lastly, run the fan off of a relay rather than straight off of the ignition switch. That way you get full power to it and max rpms out of the fan.

Don

Thanks Don
Ya know I measured the fan and its 16 inch bought it from advanced auto 1150 cfm.
I just ordered one from Jegs its not a SAL its a Chevy fan 2100 cfm 16 inch.  I get Tuesday and follow the instructions and find a good ground a see what happens.  Thanks for all your input, when the fan arrives I might have a question on the relay but until then-----johnny

[speedracer]

Hello;
I have to agree with Don. When I got my 32 Ford Victoria, It would over heat in Idle. (I live in Florida too) Until, I found out I had a major grounding problem. Now, I have the fan set up with a Flex-a-lite controller.
Just put the probe in the radiator, set the (or adjust) the on temp and off temp. Mine is set up with a relay, comes on at 180 and goes off at 170. I also have mine wired so after I shut my motor off, the fan runs for a little while. The difference is that when my fan wasn't properly grounded, you could hear it run but could hardly feel any air coming from it. Now, the * thing almost blows you over!! (SPAL 16" 2700 CFM) with a Griffin
Radiator. Never gets above 180 even when idling with the air on!
Bruce

Thanks Bruce I was just tell Don the fan I have is a cheapie from advanced auto 16 inch 1150 cfm.  I just ordered a proformance chevy electric fan its 16 inch and delivers 2100 cfm it was only 74.00 so thought I'd give it a try and also check out other stuff too, still not sure why the speed shop decided to plug off the vacuum port on the distrubtor, of course they said it was because of the cam I'm running but still does'nt seem right to me.   Thanks johnny

[enjenjo]

Ok, you are one the right track with the bigger fan, that will help. 1150 is not big enough, I have three of them on a car here, and they work ok, but not my ideal setup.

Hook up the vacuum advance, it will make a big difference at idle. If there is not enough vacuum at idle to operate it, there are some alternate vacuum controls that will work, but try the stock one first.

Hook it to manifold vacuum. Most people think this will give too much advance, but it won't. The vacuum advance works at idle when the centrifugal advance has not come in yet. This fires the mixture sooner, allowing it to all burn before the exhaust valve opens, and it idles cooler. When you accelerate, the vacuum drops, the vacuum advance retards, and the centrifugal advance kicks in. So the advance will be about the same as it is now. When you level off at a cruise speed, the centrifugal advance is not all in normally because the engine speed is lower, but the vacuum advance comes back in because the vacuum is now higher with the throttle partly closed. So the ignition advances, giving you a cooler, more complete burn, and better fuel mileage.

I have had some cars that in OD with a high gear, 2.75 or so, will pick up a spark knock at cruise with the vacuum advance hooked up, on light acceleration. In that case, I install a vacuum switch that shuts off the vacuum advance in OD only. That allows the best of all worlds, good idle, good acceleration, and good cruise.

[Ed ke6bnl]

I have dual spall 11" fans on my truck with a griffin radiator aluminum runs cool in all conditions.  the two 11' fans draw  13amps each 2780 cfm total.  A lot of fans makes some big claims, if the amps aren't there then I find they are dreaming.  I would suspect your new fan should draw about 17 amps, spals 2360 fan draws 21.6 amps.  If your new fan draw 9 or 10 amps it probably is overrated. Ed ke6bl

[donsrods]

Ed:  Interesting that you should mention you have the two 11 inch fans. The set up I  bought for my '39 has exactly that. I've never seen this setup before, and the shroud had some one-way flaps built in it to allow air to flow through when you are moving.  I haven't had the car running yet, and wondered how well it works. Sounds like you have had good luck with yours..............very encouraging.

I think all of your comments about amp draw are right on the money. It is amazing how much an electric fan will slow down with a 1 volt drop. It can make all the difference between cooling and not cooling. The relay will keep these volt right up there, especially if you run heavy enough wire from the battery to the relay, then to the fan.

Also, it looks like the concensus is that the SPAL fans really move more air than the others, especially the bargain fans. As I said, the one we got for my Son's '29 is noticably stronger than others I have owned. The man I spoke with at Daytona had no axe to grind either way, but when he told me he tests every fan that comes along, and SPAL is way above the others, I have to think he is right. He said he even built a sophisticated machine to test output, so his conclusions were pretty well proven.

[PeterR]

.......I've turned over the fan blades to blow the other way and still no difference.

Although it goes against our intuition, turning over the fan blades does not change the air direction. If you take piece of writing paper and crease the corners to make a crude propeller, you will se that if turned over, the pitch of the blades still points in the same direction.

The only way to reverse airflow is to reverse the rotation. You are not the first person to be tricked by this little oddity and I remember watching an airboat lurch backward at great embarrassment to the owner who had made exactly the same assumption.

[Ed ke6bnl]

Ed:  Interesting that you should mention you have the two 11 inch fans. The set up I  bought for my '39 has exactly that. I've never seen this setup before, and the shroud had some one-way flaps built in it to allow air to flow through when you are moving.  I haven't had the car running yet, and wondered how well it works. Sounds like you have had good luck with yours..............very encouraging.  
 
I think all of your comments about amp draw are right on the money. It is amazing how much an electric fan will slow down with a 1 volt drop. It can make all the difference between cooling and not cooling. The relay will keep these volt right up there, especially if you run heavy enough wire from the battery to the relay, then to the fan.  
 
Also, it looks like the concensus is that the SPAL fans really move more air than the others, especially the bargain fans. As I said, the one we got for my Son's '29 is noticably stronger than others I have owned. The man I spoke with at Daytona had no axe to grind either way, but when he told me he tests every fan that comes along, and SPAL is way above the others, I have to think he is right. He said he even built a sophisticated machine to test output, so his conclusions were pretty well proven.

 
Here is a picture of my setup  
http://img.photobucket.com/albums/v313/ke6bnl/Ford%2050%20F1/GriffinRadSpalFan.jpg  
 
Those fans kick in and the engine temp drops immediately they rarely run more then a couple of minutes.  I have taken the truck up to Big Bear Mtn. So. Calif. around 100 degrees through the desert and a steep climb with no problem.  This is attached to a Griffin Radiator Your engine might be bigger this is a 327/300 hp. motor with a 700r4 trans.  I spent a lot for this combination me but I did not want to deal with over heating problem and that has not been an issue.  I still have both fans coming on at the same time through a 40 amp relay.

[Land Yacht]

If the fan is between the rad and engine, you want to pull air toward the engine, through the rad from front of car to back

[parklane]

All things being equal, what is the best, pull, or push??

John

[EMSjunkie]

Johnny, I am running a 16" SPAL puller behind a Walker rad. with
A/C condenser in my Coupe.

no problems at all. control it with a Speedway adjustable
fan controller with built in relay.
works off the temp gauge. don't hafta run a wire to the sending
unit. simple hook up.

I agree with Enjenjo, hook up the vacuum advance. it really does help
with a street driven engine. Steve Jacks posted a reply to
a vacuum advance question with a link that is well worth the read.
the only time I have seen the vacuum advance plugged is on a
dirt track stock car. they are welded at full advance since most of the time the engine is at  WOT.

http://www.chevytalk.org/threads/showflat.php?Cat=0&Board=UBB64&Number=1105501&Searchpage=1&Main=1105264&Words=%26quot%3Bcamaros.net%26quot%3B&topic=&Search=true#Post1105501


just chiming in. good luck.  


Vance