open cooling conversion using stock radiator

[outlander]

DEATH TO ALL GREEN TURTLES!!!

I just got around to doing the poor mans open cooling system conversion and I can tell a difference in the temp right off the bat.

I first went to jegs and bought myself one of these:
http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_14068_-1

Then I stopped by advance auto parts and picked up a radiator cap for a cherokee that has the open system.....91+ I believe($5.99)

I mounted the filler neck just like this article details:
http://www.jeepinjoe.com/XJ_Tech/Open_System_Switch/open_system_switch.html
I didn't have to grind anything,though:dunno:

The only difference is in the interest of doing this as cheap as possible....which meant retaining as many original parts as possible(including closed system radiator),I used a heater hose repair kit to connect the hoses that went to the closed system surge tank(which obviosly gets tossed)instead of buying the different heater control unit or valve.
like this(click to enlarge)

Using the plastic heater hose repair kit tube,place it inside the smaller hose secure with hose clamp.Then slide the bigger hose over the smaller hose and secure with another clamp.
I do however need to get an overflow tank....it hasn't been a problem as of yet.

I'm very happy with this way of doing this conversion because it is very cost effective and easy to do....I have about $35.00 invested in it and it's like night and day.The closed systems " green turtle" wasn't holding pressure causing me to boil over.No more boil over and I can swear that I run cooler also,and thats always good.

 

[PornstaR]

Yep I will be doing this shortly.......... never was really sure why the heater control unit was used. I was just going to go the same route you did with splicing the lines, but I was going to run new hoses.

 

[lawsoncl]

If you've still got the original radiator, it's probably pretty clogged up by now. I'd skip the $50 Moroso adapter and put the money towards a new 92 radiator that already has the neck. Radiatorbarn.com sells a good 2-row for $130 shipped.

 

[badron]

By eliminating the control value isn't your heater running 24/7.
Did I miss it? But with you filling system you should fill the rad completely with no room for expansion. Plus I don't remember you listing a recovery tank.
The system will make room for coolant expansion by blowing some coolant out. This is fine but without a recovery tank it will be lost. Plus any key off percolation will be lost also. percolation is uncommon to the I6 but it happen on very hot days right after a hard tow or any extended stress on the engine. I would be installing a recovery tank.

 

[lawsoncl]

I think he just used a piece of hose to replace the surge tank. I can still see the valve in the picture. Personally, I ditched the valve and ran straight to the heater core. The air flow flapper in the dash blocks off flow through the heater core when you select cold so it's not a big deal. Later XJs don't have a valve either, as the auto makers discovered not having constant flow through the core made them clog up faster.

Ditto on the overflow bottle. A small 1-qt bottle is plenty.

 

[outlander]

Yep I still have the valve.About the radiator,I took it off and had it hot tanked or whatever radiator shops do,last year.I don't like replacing parts that still function....might bight me in the ass one day,though:repair:
btw the filler neck was only $26.00,alot cheaper than a new radiator....

I am no doubt loosing a little coolant running without the overflow....its only temporary untill I get one.Really doesn't matter because water is cheap and I check the fluid regularly,running alot cooler,and I have a severe habit of keeping my eye on the temp gauge because I have dual fans wired directly to a switch in the cabatriot:

 

[89jeepie]

so how do u tap in a over flow bottle?

 

[outlander]

just run a hose from it to the filler neck nipple.....

 

[89jeepie]

how hard is it to replace the water pump? iv done alot or work on my cherokee so im decent on wrenching

 

[89jeepie]

do you have to use a xj overflow bottle or can i just use one that they sell at the auto parts store?

 

[GinisKratos]

The last steps of this conversion in the artical linked in the first post confuses me alittle. Anyone able to explain?

 

[Johnnie Walker]

For an overflow bottle, you can use anything really. I would recommend using something that will withstand heat tho, as the fluid will get hot.

 

[outlander]

edit...thought he was talking about the write up I did.

 

[dannanw]

I know this is a very old thread but I just wanted to help if someone else is looking to do it. make sure of the ID of the hose you have...I followed the above link for the jegs add-in cap and I needed a 1.25 one not a 1.5 one....save your self the :banghead:and 4 letter words and get a 1.25 and it will slip in no issues.

However if you get the 1.5 (this is what I did) and need to adapt just get a 1 1/4 metal MIP available at a lot of plumbing specialty places and measure the OD of the threads the one I found is 1.5ish it now works good just a few more hose clamps...I'll put up pictures at some point, still have to get a new "recovery" bottle, also a $8-$10 one of these is a lot ezer and faster than adapting the stock bottle, but that’s just my $.02...Thanks to the OP I followed your idea and it works good...