Bit of an oddball question here.

I've got a 1999 XJ. It never came with a heater control valve. The HVAC blend door is broken, and stuck towards the hotter side of its range. This means that even with the AC on, I get minimal temperature drop on days above 75F. Two years ago I had pulled the HVAC box out to replace the evaporator and heater core, then left the heater core disconnected and ran my coolant through a filter in order to get more scale out of the cooling system without it clogging my heater core.

After reconnecting it last summer to prep the jeep for being a DD, I immediately noticed that the air conditioning wasn't as effective. It has gotten worse over time, and when I went to investigate I found the heater door would only move a small bit.

I'd like to put off fixing the blend door for the summer, and instead add a heater control valve like the older models. I know they have a lot of reliability issues though. Is anyone aware of a good reliable heater control valve that can be made to work with the XJ? Metal construction and manual control with something like a cable, rather than being vacuum actuated, would be preferred. I just don't want to go under the hood every time I need a bit of heat.

 

I'd put a manual ball valve into one of the hoses to the heater core.

 

To keep the flow through the pump normal, I would just connect the in hose to the out hose. 2 of the proper size brass fittings and a union to connect them.

 

I've looped the hoses before, then put a filter in that loop.. Unfortunately I can't hook the filter back up, I gave it to a friend.

I am hoping to use this as an opportunity to make a real improvement in the interim until I fix the blend door, and not just band aid it for the summer. A generic plumbing three way ball valve could work, though I imagine I would have to rig up an extremely sturdy push/pull cable if I wanted to actuate it from the cab.

 

all our big trucks just have a 2 fitting ball valve. Close in summer and open in winter. Very simple.

 

Just check ebay for "universal / hotrod heater valve" and you will find all metal cable operated units for $20