Coolant Questions in Mopar 440 in extremely hot climate

Joined
Apr 14, 2009
Messages
20
Location
Portland, TX
Last year while I had nothing else better to do, I got my wife's 74 Dodge Ramcharger SE (Factory 440/Auto/ w/AC) truck running/driving again.

Everything under the frame was replaced, enter fuel system, brake system, and cooling system. The truck had been sitting in my garage for 11 years with no radiator and when I pulled the water pump, it was BAD (I've attached a picture)..... I replaced everything that I suspected might be damaged and didn't want to mess up my new radiator and re-core'd heater core. After getting the truck running good enough to move out of the garage, I ran it for over half an our with no thermostat, heater core bypassed, and a water hose on adapted to the lower radiator hose and let everything coming out of the upper run off; then drained the block, buttoned up the cooling system, used 50:50 IAT - 4 gallons total system capacity (conventional green from Sams Club).

We've now put 250 miles on it on going to the beach and goofing off/cruising (at a whopping 6.8mpg average so far) but I've noticed what is extremely fine rust particles have settled out in the overflow tank which isn't surprising.

I'm going to get it up to temp with the coolant system circulating and do another flush and re-fill with fresh fluid. I'm thinking about going with a 75(water):25(antifreeze) mix along with some SuperCool (or the like) additive and wondering if it'd be beneficial. The reason why I'm asking, is that sometimes it's a 45 minute wait in the ferry line in 100* heat and I'd rather give this thing all the help I can in keeping it from getting crazy hot.
Should I also consider adding some other type of an additive like Catepillar SCA or the like as additional corrosion inhibitors?
 

Attachments

  • WaterPumpHousing02.JPG
    WaterPumpHousing02.JPG
    221.5 KB · Views: 82
  • 03-11-2021_ProgressCheck01.jpg
    03-11-2021_ProgressCheck01.jpg
    174.3 KB · Views: 79
  • 04-04-21_Beach01.jpg
    04-04-21_Beach01.jpg
    126.1 KB · Views: 81
Joined
Jul 26, 2007
Messages
284
Location
NY
Considering how bad the water pump housing was, I would run it for awhile with straight water and Evaporust Thermocure https://shop.advanceautoparts.com/p...1/12061948-p?product_channel=local&store=6353 You will need 2 containers of it due to the capacity of your system. After that I would use the mixture you said with an additive of your choice, or even less antifreeze as the additives typically work better when there is more water in the system.
 
Joined
Jun 28, 2012
Messages
2,984
Location
High Tax Illinois
Replace the water pump housing, it's toasted. Before you take it off run some more engine block cleaner in it and flush, flush, flush with NO t-stat in it. New water pump housing, new water pump and new t-stat. Use only distilled water with your favorite anti-freeze. The inside of the water pump housing is what gives the clearance for the impeller on the water pump to pump pressurized coolant through the engine.
 
Joined
Nov 12, 2019
Messages
315
Location
Upstate
Is the entire AC system a retrofit, or just the compressor? I'm thinking of replacing the old RV2 on my Barracuda because I'm sure I'll blow it up by spinning it too fast. I forget to switch it off before beating on it. 😝
 
Joined
Jan 3, 2020
Messages
450
Location
YYC
I wouldn't run anything less than a 40 (coolant) : 60 (water) mix even if you are in Texas because while water does adsorb heat better than the ethylene glycol in coolant if you run only 25(coolant):75(water) you lower the boiling point compared to running closer to a 50:50 mix. If you're concerned about lowering your coolant temp's while not moving in a vintage vehicle I'd suggest looking into a e-fan upgrade. An electric radiator fan can turn on at full speed even if you're sitting at idle and cool things down much better than a old school belt driven clutch fan that can only turn as fast as the engine is turning.
 
Joined
Apr 1, 2020
Messages
1,645
Location
Pacific Northwest
The best thing you can do to ensure good cooling is make sure to have a properly fitted fan shroud and a functional fan clutch if it's so equipped. A 50/50 mix will provide the best corrosion protection, btw.
 

shanker

Thread starter
Joined
Apr 14, 2009
Messages
20
Location
Portland, TX
Replace the water pump housing, it's toasted. Before you take it off run some more engine block cleaner in it and flush, flush, flush with NO t-stat in it. New water pump housing, new water pump and new t-stat. Use only distilled water with your favorite anti-freeze. The inside of the water pump housing is what gives the clearance for the impeller on the water pump to pump pressurized coolant through the engine.
I did, but all the rust flakes were from the old WP impeller. I soaked the WP Housing in evaporust and it came out mint, but I ended up using an aluminum one.
 

Attachments

  • WaterPumpHousing03.jpg
    WaterPumpHousing03.jpg
    166.3 KB · Views: 9

shanker

Thread starter
Joined
Apr 14, 2009
Messages
20
Location
Portland, TX
Is the entire AC system a retrofit, or just the compressor? I'm thinking of replacing the old RV2 on my Barracuda because I'm sure I'll blow it up by spinning it too fast. I forget to switch it off before beating on it. 😝
I used the Bouchillon Performance brackets as I decided after pulling the engine down to the long block not to reuse the RV2 and go with a more effecient system. I still haven't figured out which condenser I'm going to use as the original one was converted to a transmission cooler by the previous owner so I have to address that too. the Sanden will need high density/ multi-pass condenser to be effective with R-134 or R-152

 

shanker

Thread starter
Joined
Apr 14, 2009
Messages
20
Location
Portland, TX
Considering how bad the water pump housing was, I would run it for awhile with straight water and Evaporust Thermocure https://shop.advanceautoparts.com/p...1/12061948-p?product_channel=local&store=6353 You will need 2 containers of it due to the capacity of your system. After that I would use the mixture you said with an additive of your choice, or even less antifreeze as the additives typically work better when there is more water in the system.
I never even knew that product existed, but I'm a big fan of Evaporust already. Thanks!
 

shanker

Thread starter
Joined
Apr 14, 2009
Messages
20
Location
Portland, TX
The best thing you can do to ensure good cooling is make sure to have a properly fitted fan shroud and a functional fan clutch if it's so equipped. A 50/50 mix will provide the best corrosion protection, btw.

I wish it was that easy, I do have a 26x21 true 4 core copper radiator, 7 blade HD fan, but the fan shroud for factory big block/air conditioning trucks is pretty elusive. I'm leaning toward fabricating my own.
 
Top