383 Stroker Getting Hot

[Faulk21NG238]

I am having problems keeping my 383 stroker cool in my 80 Malibu. Below is what I am running for a radiator.

Radiator Style - Crossflow
Row Quantity - Dual-row
Radiator Material - Aluminum
Transmission Cooler - Yes
Inlet Size - 1 5/16 in.-1 1/2 in.
Outlet Size - 1 1/2 in.
Core Height (in) - 18.250 in.
Core Thickness (in) - 2.250 in.
Core Width (in) - 20.750 in.
Tube Size - 1 in.

50/50 anti-freeze water mix

Water pump is a Tuff Stuff Supercool High-Volume mechanical pump. Fan is a 17" electric set to come on at 160 degrees.

On a hot day (80-90 degrees) in traffic, the water temprature gets above 240 degrees and continues to rise (has never been above 245). If I am on the interstate, the temp steadily goes down, but only if there is a lot of air coming through the radiator. If I shut the motor off, I have to wait for the engine to cool off before it will start again. Dont know where to begin to look for the problem here. Thanks for any help I can get.

 

[454cutlass]

does it over heat if left at idel. do you have the rubber flashing that directs the air into the radiator. test the thermostat

 

[bill]

Are you 100% sure that the fan is working? My fan is suppose to come on at 185degrees...but the gauge says 210 when it kicks on. Since the probe is in the radiator, and the sender is at the thermostat, this all makes sense in my case. Once the fan kicks on, the gauge temps drop to 190, as it should. Where do you have the radiator temp probe? Mine is in the top of the radiator, nearest to the hose coming from the water outlet. I know some engines run pretty hot, but that sounds a bit too hot. Your fan should cool the engine sitting still.....jmo

 

[Ringers]

A two row radiator may be a little small, for a 383, I'm thinking. Measure your temp at the radiator inlet and at the outlet. There should be at least a 30 or 40 degree differential. If your radiator is acting OK, it may be your thermostat or fan. It can be difficult to chase down, but not impossible. Get some good test equipment, validate your instrumentation. Pay attention to details and be thorough. Invite some pals over and pick their heads too. Good luck.

 

[Tuggy24g]

I am not sure what fan setup is, but I would say that you need to get dual fans with a shroud. I had the biggest single fan I could get but it did not have a shroud. So a lot of the engine and water plus air was not getting cool. Now I have a flex-a-lite dual fan with shroud and a custom rad. On some of the hottest days in Philly still does not get over 170.
Here is the fan setup I have
http://www.ebay.com/itm/Flex-a-lite-Low ... es&vxp=mtr

 

[Faulk21NG238]

Yes, the fan is working correctly. The probe is in the radiator just to the right of where the water returns. My gauge probe is next to the thermostat. When the water temp on the gauge reads 160, the fan comes on. On a cooler day (70-75) the fan does a great job and cools the water temp down until the water temp reaches the thermostats setting. The probelm is when it is hot out.

Even on a hot day in Indiana it takes some time for the engine to warm up if I am driving down the road. Once I am in traffic, or stopped at a red light the water temp keeps climbing. Like I said, once I start accelerating and have air coming through the radiator, it will slowly cool off.

No, either side of the radiator is left open. The first thing I thought to do was block this area off to force all air through the radiator. Will this make a big difference?

 

[dogsht]

Sounds like fan shroud. If you don't have a fan shroud that fits the fan properly or at all your fan will not be able to suck the hot heat that almost sticks to your radiator fins once the heat gets to a certain point. Works fine until you reach a combination of not enough air flow and too much heat.

If you have a fan shroud that fits properly ie about 1/4 to 3/8" all the way around your fan and at least comes close to sealing to the radiator. Then your electric fan may be too weak to suck hard enough. Is it an OEM electric or quality aftermarket or cheap autoparts store. If it doesn't at least require a 30 amp fuse its probably on the weak side for when its actually pressed to pull heat.

 

[bill]

Check for a stuck thermostat too.... As for a shroud, that would be a definate plus as well. I would bet this problem is coming from one or the other....or both.