olds 455 heating up

[1Bad4558]

I'm leaning toward air flow problem. It's never really had a problem keeping cool till the last few times I drove it. Last year when it was 100 degrees it never had an issue staying cool even in traffic. I'm gonna try a new clutch on my fan and put them flaps around my rad and see what I come up with. Have any of y'all had any experience with a direct drive fan?

 

[foxtrot]

If this was not the case, running an engine with no t-stat would make the most sense....yet anyone who has tried that will tell you it has the exact opposite effect.

Bill,

I do agree that the thermostat does help the car warm up faster but I don't agree with the fact that a low temp or no thermostat will make the car run hotter. From a thermodynamic point of view it's all about the amount of coolant moved and the car will not run hotter without a thermostat installed. Once the car is up to temp, the thermostat is probably opened more than it's closed; especially with some of the older engine designs. That's my two cents..

 

[foxtrot]

I'm leaning toward air flow problem. It's never really had a problem keeping cool till the last few times I drove it. Last year when it was 100 degrees it never had an issue staying cool even in traffic. I'm gonna try a new clutch on my fan and put them flaps around my rad and see what I come up with. Have any of y'all had any experience with a direct drive fan?

I'm thinking that with the GM HD clutch & fan setup you can't go wrong. The fan only really comes to play with low speed operation. Once the car is moving along, there is way more air flow thru the radiator from the outside of the car than the fan.

 

[bill]

If this was not the case, running an engine with no t-stat would make the most sense....yet anyone who has tried that will tell you it has the exact opposite effect.

Bill,

I do agree that the thermostat does help the car warm up faster but I don't agree with the fact that a low temp or no thermostat will make the car run hotter. From a thermodynamic point of view it's all about the amount of coolant moved and the car will not run hotter without a thermostat installed. Once the car is up to temp, the thermostat is probably opened more than it's closed; especially with some of the older engine designs. That's my two cents..

Maybe so....water wetter couldnt hurt.

 

[foxtrot]

Bill,

Water-wetter is great stuff and really does improve the coolants thermal transfer ability! 50/50 coolant mix also is good.. I'm thinking the radiator flaps will also really help the op's cooling ability too.

 

[olds307 and 403]

I have run no thermostat before, it definitely ran cooler at low speeds. It ran about the same at highway speed and still got hot towing my boat. The 3 core Champion rad just wasn't big enough, ran at acceptable temps otherwise. I run a high flow EP Stewart modified with 3 bypass holes drilled Robert Shaw 160 thermostat in my Cutlass. What temps is it actually running?

 

[olds307 and 403]

 

[olds307 and 403]

 

[olds307 and 403]

 

[foxtrot]

I think that the 2.5" three core campion is made well and cools good for a 307 but there are other options for a 403 or 455. One issue with the bigger 3" radiators is the fact that the shroud & possibly the Hold down will need to be modified to make it fit. Do you know what it takes to install one of the 3" thick radiators into a g-body?