wgc68nyc

Over the last weekend I finally spent some Amex points on amazon and got a second spal fan. Ive been running too warm at highway speeds (60 and above) and despite having flushed the coolant system and fiddled with timing it still ran warm. I got a 14in pusher (9amp) to go in front of my A/C to help with the hipo Spal 16in (22amp) puller on the radiator. The difference was big....at idle the engine would cool with both fans running to the point the termostat temp dips below 180 which is when it will close. This was in 80+ degree weather. This helped me conclude concern I have:

- There is too much space between the AC condensor and the radiator (almost 2 inches+)

Essentially air takes the easiest path and would go through and around the condensor. The puller was only pulling whatever air came through the condensor hence why despite its power it would not cut it. With the second fan force air through the condesor at a high velocity the rad stayed cooler.

Want further proof? The 14 pusher fan was almost more effective at idle by itself than the 16in puller.

I still run on the warm side on the highway but hopefully with the use of some spacers I can sandwich the rad and condensor to the point they are almost touching which should yield better results.

Also....I regret getting a higher stall converter....at 60mph im at 2100rpms which means in all likely hood I am still getting a bit of slipping. The trans cooler I have has helped but first chance I get I am going back to a stock which is honestly what my car is cam'd for anyway. MPGs have suffered too.

wgc68nyc

On a side note could I be running too lean on the highway based on a bad carb adjustment? I have a Edel perf 500 and a pertronix 2.

jonward786

If you're getting hot on the highway it could be a sign you're thermostat is stuck open. I'd start there. Putting another fan in front of the radiator will not solve your getting hot at highway speeds problem. At high speeds, that airflow coming into the radiator should be more than adequate to cool. You only really need a fan while not moving or moving slowly. What you should do is properly utilize your puller fan. I'm guessing you are just hanging it from the radiator like ive seen a lot of people do around here. Treat your electric fan just like mechanical fan and use a shroud that covers the entire radiator. Here is what I use with my 68's radiator:
http://www.northernfactory.com/HIGH_...NG/1968/Z40069

wgc68nyc

The champion 3 row rad I had came with a aluminum shroud but it seem to run cooler without it. I am guessing if I had more room to back the fan off the rad and shroud it then it would work better I don't have the space. The other option would be to mod the support and try to move the rad forward against the condenser but now we are talking cutting and fab'in some bracket.

Here it was with the shroud but with the fan inside which probably had a negative effect



Unless I move the rad forward I have 1/2 inch to the pump which I discovered is likely from a 70 or later as it is a driver side outlet. I dont know if those pumps stick out further but I can only get 2more inches at best.

I guess I have to hope bringing the condensor back helps.

The Alien

I want to say something really but really stupid so, my apologies in advance but...

did you check the fan wires? is it running on the right direction? the airflow should be the same as the driving airflow.

I'm sorry about that but I didn't understand well if the fan was originally mounted on reverse or not

wgc68nyc

Don't feel bad....at one point I wondered myself but no they are right.

The Alien

without being there I could guess many stuff that maybe you already checked but the first thing I have in my mind is the waterpump,

You had this problem when you replaced the radiator or there was something else before?

wgc68nyc

I am tempted to replace the pump but I use to run cool after the rad was installed but before the AC....should probably just pony up and do it. I dont know if she was ever burped correctly so I will try to do that as well and check with the cap off to make sure the impeller is pushing well.

The Alien

yep it seems a air bobble somewhere.

even with the AC off you have overheating?
I never saw this engine and on the picture I'm not sure to see if the compressor is using the same water pump belt

The Alien

another thing: the ac condenser has the honeycomb as the same orientation than the radiator right?