87-91 vs 92 - up cooling systems

[Ecomike]

5-90, this 5-10 year bottle life you speak of, is that parked in the driveway 7 days a week?:laugh3:

Most of us are lucky to get 3 years and that is for a light duty spare vehicle, not DD use, no mater where we buy the POS bottle, LOL. Many have been reporting 3-6 month life spans lately, no mater where they bought it.

 

[5-90]

5-90, this 5-10 year bottle life you speak of, is that parked in the driveway 7 days a week?:laugh3:

Most of us are lucky to get 3 years and that is for a light duty spare vehicle, not DD use, no mater where we buy the POS bottle, LOL. Many have been reporting 3-6 month life spans lately, no mater where they bought it.

Hm. They must be making shonky bottles then - glad I stocked up a while ago.

No, you can't have any!:gag::spin1:

I suppose I could eventually see about one of those aluminum TIGged bottles, but that would require that I come up with a ton-fifty that isn't needed anywhere else straight away...

 

[RTFM]

Kelley - great site.
I will poke around it more later, but I like what you've done and have to offer!

 

[5-90]

Kelley - great site.
I will poke around it more later, but I like what you've done and have to offer!

I do what I can.

Note that I'll be moving it sometime in the next few months - Yahoo! is closing down GeoCities in October, and I think I can finally justify kicking open a domain anyhow. The link in my sigs (on this board and plenty of others) will change about that time - so I'll still be easy to find.

 

[lawsoncl]

5-90, this 5-10 year bottle life you speak of, is that parked in the driveway 7 days a week?:laugh3:

Most of us are lucky to get 3 years and that is for a light duty spare vehicle, not DD use, no mater where we buy the POS bottle, LOL. Many have been reporting 3-6 month life spans lately, no mater where they bought it.

The oem bottle made it to 190k miles. Then I went through 3 of the crappy plastic surge tanks in 2 years before I gave up and converted. One split in half and the other two stripped the threads on the cap. The worm-gear trick might have solved that though.

 

[Saudade]

There are plenty of threads covering the conversion. A "full on" conversion will require a new radiator, new heater control valve, an overflow bottle, and possibly a few hoses. Could be done for around $200 in parts. The open rad has no temp sensor in it for the elec fan so you have to either rig one up in the t-stat housing (then you need one of these too) or use a switch.

Here's one: http://jeep.off-road.com/jeep/article/articleDetail.jsp?id=257864

If your rad's in good shape, you could get an inline filler neck (placed in the upper hose, new heater valve and overflow bottle. No need to mess with the e-fan sensor.

Here's one: http://www.madxj.com/MADXJ/technical/technicalfiles/JTopenSystemSwitch/OpenSystemSwitch.htm

Some people bypass the heater valve and just connect the core. The blend door should block airflow through the core.

My 88 is still closed and works fine in the SoCal heat.

 

[RTFM]

When all my issues started I found the open cooling site at your first link, which got me thinking about it.

Then Ecomike turned me to his thread on the plastic bottles, and I think I'll keep it a closed system, but after my complete bottle failure on Wednesday, I've decided to go with Mac's aluminum tank this week.

The radiators new (2007) but it's a 2 core, I think I may put some hood vents in too just to get some of the extra heat out.

 

[tbones88XJ]

I've been looking for a solution to the same problem on my 88. I have bought 3 jugs in the last 2 years, cost enought to have got the newer rad. Thanks for the answer to my problem, looking forward to a lot of fun on this site.

 

[Ecomike]

When all my issues started I found the open cooling site at your first link, which got me thinking about it.

Then Ecomike turned me to his thread on the plastic bottles, and I think I'll keep it a closed system, but after my complete bottle failure on Wednesday, I've decided to go with Mac's aluminum tank this week.

The radiators new (2007) but it's a 2 core, I think I may put some hood vents in too just to get some of the extra heat out.

Speaking of hoods, I checked mine the other day and it was 158 F, and the XJ was parked, not driven. Later after a good drive it was about the same.

Got me to wondering if the bottom side hood insulation helps us, or hurts us in the summer. Same question goes for a hood with a no insulation.

No apologies for the highjack!:laugh:, he is the one who mentioned HOODS!

 

[Ecomike]

I completed my upgrade improvements and tests today.

Today, I discovered that my system, which has several cooling improvements now has hotter coolant exiting the radiator, than before the changes I made, but the system, tested at the thermostat is running cooler than before. The only reasonable explanation I can find is that my 4 year old 2 row alumiunum radiator was restricting flow (I was getting 30-40 F delta across the radiator which had me thinking it was working properly, but it was 4 years old), and my new CSF, 3 row copper/brass radiator has only a 15 F delta T across the radiator at idle today. :dunno:

All I can figure is I am getting a lot more flow through the entire system now as my peak thermostat temp is down a good 20 to 30 F, while the new radiator exit temp is up 10 to 20 F!:dunno:

I now have a 15 F delta T between the engine inlet (radiator exit) and engine outlet (radiator inlet), where as it was 30-40 F with the old radiator. Only other change I made was a new AC condenser.

My final changes included keeping the Renix bottle (closed system), upgrading to a Stant brand after market Volvo bottle cap (20 psi rated), an inline filer neck in the upper radiator hose to ease getting air out of the radiator, a 16 psi (for now) radiator cap on the filler neck (open system feature), a CSF 3 row, copper / brass radiator, a ZJ mechanical fan clutch, ( new OEM water pump installed 3 months ago with a new T-stat), and a replacing the 87 AC condenser with a parallel flow (high efficiency) AC condenser.

AC cools better than ever, AC pressures are down from a 385 psi Peak to the low 200 psi range. Today it was 95 F, took her out for a 66 mile round trip 2 days in a row. It never got over 207 F at the T-stat housing, at idle after a long hard drive.

Back on topic, I essentially integrated a closed and open system into a hybrid, succesfuly. It is however, still basically a closed system.

That said, I am now ready to make the claim that the closed systems are truly closed when they are working properly, Not leaking due to a malfunction, as they never reach the cap pressure to vent due to the compressibility of air in the bottle, while the open systems are constantly letting out and sucking back in coolant as they heat up and cool, due to the incompressibility of liquids.

 

[bcmaxx]

Hi Ecomike, I just got the inline filler for my 89 4.0. I got it for a few reasons, first to have a place to fill the system if the surge tank ever fails, second to help burp my system. It tend to run good temp wise until I pull a steep hill and it gets hot rather quickly, and in cold temps I have to block the grille on the rad to keep warm, so I'm fairly certain there is some air in there. Would you recommend losing the surge tank? It really hasn't caused me any problems.

 

[Ecomike]

Hi Ecomike, I just got the inline filler for my 89 4.0. I got it for a few reasons, first to have a place to fill the system if the surge tank ever fails, second to help burp my system. It tend to run good temp wise until I pull a steep hill and it gets hot rather quickly, and in cold temps I have to block the grille on the rad to keep warm, so I'm fairly certain there is some air in there. Would you recommend losing the surge tank? It really hasn't caused me any problems.

I have kept my surge tank. Having air in the surge tank allows the system to run at lower pressures, as the air is compressable. Air in the closed system is not the problem by itself, it is where the air is located that can be a problem. Air in the top of the surge bottle helps reduce system pressure and stress on the hoses, but air in the radiator or engine block can block flow, in the engine it can lead to hot spots, in the radiator it leads to blocked flow, reduced flow, and reduced heat removal.

I am having great luck with the filler neck addition and keeping the Renix surge bottle.

 

[AJTorris]

Hey guys i have tried to search and i cant seem to figure out my issue.

My top radiator hose never has pressure in it. Would that mean that my thermostat is shot?

 

[heyhar]

The system only goes to about 14* pressure. Don't know if squeezing is an accurate measurement. Does it get as hot as it should, just by feel? T-stat wound be a good place to start, especially if you don't know how many years/miles the old one's been in.

 

[Ecomike]

I am assuming you have a stock renix system?

If yes, 4 possible problems.

1) Air trapped in the radiator.

2) T-Stat is stuck closed.

3) Water pump impeller is not turning, thus not pumping.

But my money is on a

4) bad cap, not holding pressure.

On the other hand, a working Renix system has a lot lower operating pressure that the HO open systems. If the T-stat is stuck open, weather is cool, and your not getting over say 160 F that hose will not be hard on a Renix.

So other than a soft hose (and how soft is the reAL QUESTION????), what else makes you think there is a problem?

 

[RTFM]

Good on ya' Mike. Hope it works well for you.

I think I can safely say I have found and fixed all of my external coolant leak issues:exclamati

My Jeep no longer marks its spot with oil, coolant or transmission fluids:exclamati
:sunshine:

I'm going to replace the fan clutch to the ZJ - you and Joe appear to like them quite a bit, and going to cut in an electronic fan bypass switch so I do not have to switch the AC on just to get extra CFM.

The issue I have now is my ambient air temp is in the high 60's to very low 70's now. So I can idle all day long and not reach a boil over like I could when ambient was 100+..... so I'll make the changes before next summer - but my new bug is no rear window defrost - (blows the fuse) so back to the multi-meter......

We work on these for sport and fun riiiiight? :viking:

Hood vents are on the medium long list for next year too..... would like to have it running well enough to do a meet and greet in Moab in 2010 - may not wheel it cuz' it's still stock height, but would be fun to meet the gang.