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RENIX heater core flush ... assistance required.

The Renix closed system if properly maintained is supposedly a great system...but I've always found it to be problematic. Between the odd hose setup and the pressure bottle and/or the pressure bottle cap usually being a piece of crap. I have converted both of my Renix rigs to the open cooling systems with 97+ hoses and a new radiator and no heater valve. I have had no significant issues caused by this conversion and mostly all positives. It's a fairly simple conversion, but it does cost around $200 (including the radiator and hoses and a radiator cap) for parts and an afternoon for a shade tree mechanic.


Same here. I'm of the opinion that if you need to replace the radiator, you're best off converting and getting rid of the fail-prone pressure bottle and heater valve. There are a few staunch supported of the closed system, but they tend to be the guys that spent a some effort getting it reliable and replace the bottle every few years.
 
If you "converters" had one of these installed, you probably would have stayed the course;

coolantbottle1503634246.jpg
 
If you "converters" had one of these installed, you probably would have stayed the course;

coolantbottle1503634246.jpg

Im still using plastic bottles, i used the volvo bottle cap, and install a brass 3/8" pipe nipple in the bottom plastic nipple. Im getting a good 8 years out them, but one needs to fix any other real overheating issues first.
 
Success! The fantastic heat is back and ready for Canada. As a shade tree mechanic, it took me some time to get those old hoses off and the new ones on. The new top hose had slightly smaller inner dimensions on both ends and had me concerned but I was able to get it installed. The lower hose was a closer fit to the original.

There was noticeable dark matter that flushed out. I measured around 100*F prior to the flush and around 140*F after a few minutes of run time.


heater-temp21504916065.jpg
 
Oh Crap! Went to check the heater output and ... nothin!! Looks like the HCV is acting up now. Hot coolant in, cold on the other side. Vacuum line hooked up and seems to be operational. I just visited the JY last week and someone got to the HCV before I got there. Went though my parts boxes of stuff I collect every-time I visit the JY and found this ... I hope it works. Whew!

135624hcv21505523656.jpg
 
Yeah, those things are prone to failure, especially the plastic ones that crumble when you look at them funny. Jeep and most other car makers got rid of that valve because turning off flow through the heater core for half the year makes them plug up faster. Unless you're in a really hot environment, you'll never notice the difference if you eliminate this valve altogether.
 
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