Recommended Coolent for 7.4 TBi FWC

[CaptJoe3]

Ive been having overheating problems. Have done everything we can think of except change brand of coolent. What is the recommended coolent for these engines?

 

[AllDodge]

It's not the type of coolant unless you or another has mixed types together

Have you rodded out the heat exchanger (HE)?

Go to the hardware store and get some clear hose, barbed fittings and a few hose clamps. Place a short piece of hose where raw water enters and where the raw water exits the HE. Run the motor and look for bubbles

If no bubbles place a piece of hose between on coolant side between HE and thermostat housing

 

[CaptJoe3]

Yes, HE tubes were rodded and inspected. Bubbles no longer issue. Plenty of water flow. Coolant not mixed, always used Prestone 50/50. Thanks for your reply.

 

[AllDodge]

Overheat is always one of two things.
Not enough flow of raw water thru HE or something is displacing coolant as in blown head gasket or such. Keeping heat below limits is not hard, but if there is a head gasket leak it produces bubbles into the coolant side. The air bubbles reduce the amount of cool entered into the block.

You have one of the two, need to figure out which one