Open Colling system ???

[BIGSLVRXJ]

I switched to the open system on my 2 older XJs because the pressure bottle and valves seem like they were always leaking. I never had a problem with my closed system overheating, but for the most part I was meticulous in maintaining it. I followed 5-90's advce and drilled a hole in the thermostat at 6&12 o clock and that made it self bleeding. To me it was just the bottles and valves that frustrated me. I went through 3 of the expansion tanks on my 1990 in 2 years, and they were new aftermarket "reinforced" bottles. I know the next comment that will come up, "well you must have had other issues with the engine causing excessive pressure" but I didn't, once I switched to the open I had no more problems with anything cracking. The fact is I just got sick of replacing bottles and I wanted to delete the heater control valve. Now that all of mine are the open system no more pressure bottles, and no more heater valve to worry with. I take it one step further and delete the overflow bottle too, even easier. Just my .02.
-Collin

 

[outlander]

how do you get by without the overflow bottle?I bought a open system resevoir and the freaking thing is tall and gangly

 

[BruceB83]

I meant open system...
....every time this topic gets brought up it is the same thing:banghead: .I stated my opinion on the closed system,that makes me a bad person?

ok lets put it this way.If you like to throw money,time,and energy into the closed system it works.....

if you are like me and are tired of "maintaining" the closed system which is prone to boiling over and losing coolant and possibly overheating your motor switch to the open system.

:badpc: ...this is why I hate the internet. Ok, I don't recall saying you were a bad person. Lol....come on dude, you're really blowing this thing up getting all mad and everything. All I said was I have no problems out of mine. Sure, the tanks can crack. The heads on the '01 (I think '01) XJ's crack....does everybody who owns one of them go out and swap it....no. I just didn't want him to think, by your comment, that if he didn't go swap his system that it was going to blow up on him. You could probably put up a poll on the main page asking how many people actually had their OEM tank blow up....I would guess it's probably 1 out of every 10 or more people and they probably had alot of miles on them and have had previous overheating problems. If you don't have overheating problems to being with, the tank will not be overstretched as much so the liklihood of that happening is reduced.

That's all. Now, if I wanted to put the money and time into converting to an open system, would I, yes I would. But there are other things higher on the list. It's not a life or death thing right now. You made the closed system out to be the :firedevil. Did you have a really bad experience with yours?

Now, can we be friends now? eace:

 

[lawsoncl]

any part can fail leaving you stranded on the road.

i have never had the expansion tank fail and leave me on the side of the road.
1989, daily driver since 1990, 226k miles, never standed on the road.

I have. The bottle was less that 1-yr old. First really, really cold morning of winter (-15*F) I made it about 5 minutes down the road before I was engulfed in a huge steaming cloud coming from under the hood. F'ing bottle split into two pieces. The next bottle and cap was purchased from the dealer. It made it 4 months before it started spitting off the plastic cap and boiling over. Since it had the original radiator, I opted to redo everything using a 92 open radiator. Been working great ever since.

 

[Blaine B.]

I have a 89 XJ, closed cooling (yeah it blows) If I cut in an after market filler into the top hose does this make it an open system?

Thanks
Kenny

Yes, it would. You would have to rig up a new resivoir though, deleting the sealed resivoir.

 

[fuzzydog]

The last two (very distressed) XJs bought were at auctions (usually $50) it is amazing, but both of these were missing fan shrouds.

That would be because the passenger side engine mount broke on them and dropped the engine to the frame rail, causing the fan to eat the shroud. I'm just saying....

 

[fuzzydog]

Wow, it seems some like the closed system, and some dont. I cant change the raidator right now, so I can either cut in the filler can to the top hose, or install a knew pressure bottle. 6 of 1 1/2 dozen of the other. When the closed system worked I never had a problem with it. The cap on the bottle went bad and so this is where I am with this. Thanks for all the replies, I really enjoyed reading them all.

but what if the radiator IS your problem? still can't replace it?

Here is my real world experience - when I bought my 90XJ it cooled just fine but within a year or so of owning I noticed temps getting higher faster on hills, then pretty much all the time. finally blew a hose because pressure got too high due to high temp (and it was an old hose). So I did it all - replaced the turtle, all hoses, flushed the rad and heater core, replaced t stat, water pump, switched to a high cfm electric fan....everything EXCEPT change the rad. it still got too hot. So I changed the rad.
Now, I run 90% of the time without my electric fan running - note the mechanical fan is GONE. I run 90% of the time with no fan pulling air through my rad and temp stays right around 100 C. At stop lights it will creep up but come right back down once I get moving again. I can do a several hundred kilometer trip on the highway, up hills, through towns, and never once have to turn on the fan. I have to admit though, that the replacement rad is an alum core with plastic end tanks and the alum seems to dissipate heat much better than the copper/brass rads.

Regarding your coolant bottle (closed system) - I strongly recommend that you look at the hoodliner right above where the cap is. I bet you will see evidence of contact between the cap and the hood. If you just replace the cap or bottle, it will go again in short order as everytime you close the hood it will damage the threads on the cap or bottle. I removed the bottle and bent the mounting plate downwards to eliminate this contact.

 

[BruceB83]

Regarding your coolant bottle (closed system) - I strongly recommend that you look at the hoodliner right above where the cap is. I bet you will see evidence of contact between the cap and the hood. If you just replace the cap or bottle, it will go again in short order as everytime you close the hood it will damage the threads on the cap or bottle. I removed the bottle and bent the mounting plate downwards to eliminate this contact.

Ooh....good point. Never really thought to look at that.

Yeah, those all metal radiators make a big difference. That's what I am running on mine...that's what I run on all of mine.

 

[outlander]

bruceissing matching over the net are a waste of time....
and yes I've bad experience with three jeeps,all had the closed system.

 

[kenny811]

When the cap went bad the first thing I looked at was the hood, about 1" from what I can tell. No the threads on the cap and bottle are just wore out. 185k will do that. I never thought this topic whould go like this. I am at this point completly convinced thats the differance between the open / closed system is simply the owner of the jeep. To me and only me the pressure bottle is just one more thing to fail in the system.