12.7 detroit 60 series running too hot

mine was brand new only had it on the truck 2 weeks piece of crap

 

I got two identical trucks, one with k31 and one with 702, same tune. Turbo has nothing to do with that.
K31 has over 200k on it. Maybe you got a fake one or something and not original Borg ?

 

still have the k31 in the shop ill post a pic of it 100% sure it's a borg warner

 

I don’t know how hard it is to remove the grill on a Coronado. If you can, being able to stand up in front of everything with the hood open, sure makes removing the cac, and carefully setting the a/c condenser aside. Hopefully it’s just got a layer of oily dirt covering the front of the radiator. If the fins are corroded and fragile, it can take a long time. Soak in pb blaster if corroded bad. use a zip tie or a small screwdriver. Maybe some brake clean. Anything will work to clean it. Product called evapo rust if needed to loosen corrosion, won’t damage aluminum. Maybe a wire brush to poke it through. You can buy a “fin comb”. Whatever works. They sell a/c coil cleaner at Big Box stores. Most of it has a small amount of acid. Probably work good. I’d spray some baking soda mixture afterwards just in case, let it sit, then rinse it off. Neutralize the acid. A couple light coat of good paint afterwards helps. Auto parts store sell a “radiator paint”. It’s just thin paint. Just don’t want to plug up the clean fins. To keep it clean afterwards, rinse it first from backside, turn fan on, then idle it up to 1300-1500, spray it from the front. Pulls all the water through. I’ve done that as a temporary fix, so I know it works. If it still runs hot, might be plugged up inside. I’ve used the evapo rust to flush the inside of the system. They make a special radiator flush, it’s half the amount for twice the price. I just used the regular stuff. Mix in a half gallon or more as you fill the radiator with water. I would isolate the radiator though, keep it out of the engine. Just in case. Let it sit in the radiator at least an hour, maybe do it a couple times. Even let it sit overnight. It works. Will buy you time before replacing the radiator. Nothing beats a brand new radiator though!! Hopefully the bad mpg is from the fan running too much. I think it takes up to 70 hp? Good Luck,

 

I've regularly flushed my trucks and reefers at about 400-500k, 5k-8k hours respectively. I used radiator flush, but never tried evaporator rust. I'll have to try it myself someday. Whenever I flushed, the amount of corrosion that came out always was a lot it seemed. I would pay a shop to only dump my oil, and then refill with distilled water I bought from a Walmart right before and the radiator flush. I would buy that at a shop. I always got the shop rate for 1/2 hr. I'd do it about 1-3 hours before I got home to give it the necessary amount of time to clean good. This way cleans the coolant galleys in the block too. I would drain right away (still hot) so the corrosion might still be suspended in the water. I can't say this will solve your problem. But I've never had cooling problems on the older Detroits that I've had, and my reefers as well. Like already said though, nothing beats a new radiator.

 

You can do that, or just some dish soap and gentle water pressure. Just flush backwards from air flow. They have real problem collecting dirt. Would recommend doing this once a year.

 

AC on in the daytime and off at night?

Condenser adds alot of heat to rad.