Cooling trouble

[AEM67M715]

I have a 67 M715 that I have put in a small block chevy conversion, the clutch fan sits about 3.5-4 inches from the radiator. As long as I am not really on the motor it is 180 degrees but what can I do to get the fan closer or what do you recommend for a shroud? The temp creeps up of high prm driving.Thanks I'm trying to keep my cool.

[randyscycle]

Several things:

First, a shroud is definitely a plus, but usually will only be more effective when idling. Moving down the road there is enough ram air to keep things cool.

Is the radiator new or very clean? If not, once moving the engine is generating more heat, and will have a harder time staying cool with a plugged or partially plugged radiator.

Check the lower radiator hose. Be sure it has the spring inside to keep it from sucking shut when the pump is pulling the water from the radiator back to the engine.

What thermostat are you running? Be sure its not stuck partially closed or fully open.

Is the fan belt tight?

What type of radiator cap are you using? What pressure?

[BubbaWilkins]

If you find that there is no blockage of air flow, you might consider just removing the fan entirely and replacing it with a couple of electric ones mounted directly to the radiator.

[Doug]

Don't forget the almost unrelated stuff.

Timing to far advanced? Running lean?

[AEM67M715]

Thanks for the ideas, I will check all this out and get back, I know that the thermostat is 180 degrees, I just build the motor and it's brand new. I will check the belt on the fan, and their is no spring in the bottom hose, Where can I find one of these? It had an electric fan on it but it did not work well so I replaced it with a clutch fan. I really appreciate all the feed back, I will get it right one of these days. The radiator is from the inline 6 , and this is a different motor will this matter?

[Doug]

A small block V8 does require more cooling than the stock 6, but, many run the stock one with little issue. I do and it only gets hot when I end up with the radiator 1/2 full of mud.

[AEM67M715]

Do you have the large gap between the fan and the radiator on yours?

[Doug]

At most, 3" or so.

I was running a home built shroud until my last engine swap, didn't bother to put it on again yet. Without it, my temp will run a few degrees higher are low speed/high load climbs. Hasn't proven to be much of an issue.

[Barrman]

I don't have a shroud on mine and I can tell in traffic, parades and long hill climbs. That is with a huge aluminum radiator.

When I was still running the stock radiator with the 396 behind it and a twin Taurus fan trying to cool. It didn't work to good when the air temp was above 95. It did ok in town, but not on the road.

The closer your fan is to the radiator, the more air it should theoretically pull. A shroud really increases the efficiency of the fan as well.

[Doug]

A shroud is the way to go. Eliminates the need to get close to the radiator. Get too close to the rad and drop the front off into a deep water hole and the fan blades will paddle themselves forward and act like a hole saw on your radiator.