[prostreet64]

Got the Bird up and running several weeks ago after the engine rebuild, and first test drive the temps were going up to fast and too high, 205 after just 10 minutes or so. Knew we had a radiator issue from before the rebuild. Since we don't have a local radiator shop we decided to try this irontite flush. Followed the directions exactly and then took another test drive. Temps held steady at 182 after 25 minutes of stop and go and some highway speeds. All kinds of scale came out in the flush process so we were pretty sure the temps would be close to where they should be. Will do one more drain and fill to flush out any remaining residue and should see another degree or two lower. Using straight water and Rislone Hyper-cool.

[Half-Inch Stud]

Maybe the coolant was low? Just being 4" down in the radiator will cause rapid head heat.

[prostreet64]

HIS, we purged the air and topped off the radiator with a gadget from Harbor Freight that allows you to add water as the air bubbles come up and out of the radiator. Did this on both test drives to make sure we weren't adding to our problem. Deposits in the rad were definitely affecting heat exchange.

[chuckies76ta]

A little trick I always do when draining and filling the rad is to remove the thermostat housing and the thermostat and fill the rad till coolant starts to flow into the cross over. Doing this makes sure the block and heads have all the air out of them. Looks like your probably running a 180 * thermostat. You could always upgrade your rad to Aluminum which will be more efficient. I'm just assuming your running the stock one. Another thing to stay away from tap water as too many minerals, and use distilled water. It will get rid of scaling in the rad. Nice to see engine running good for you.

[Half-Inch Stud]

I got lucky; 3-core Harrison radiator from a 72 LeMans parts car, that was clean inside.

Ran it with a 455+060, half-filled with cement, no mech fan, and it did rather well. Elec fan was used for some long stoplights and bumper traffic.

[prostreet64]

Originally Posted by chuckies76ta

A little trick I always do when draining and filling the rad is to remove the thermostat housing and the thermostat and fill the rad till coolant starts to flow into the cross over. Doing this makes sure the block and heads have all the air out of them. Looks like your probably running a 180 * thermostat. You could always upgrade your rad to Aluminum which will be more efficient. I'm just assuming your running the stock one. Another thing to stay away from tap water as too many minerals, and use distilled water. It will get rid of scaling in the rad. Nice to see engine running good for you.

We have electric water pump and electric fan which made the whole process easier and we did remove the thermostat for our drain and refill process. The radiator is aluminum. Also we use filtered water with the Hyper-cool. Thermostat is 180*.