• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Which radiator?

R

RyleyF

NAXJA Forum User
Location
Boone, NC
I'm pretty sure my 89 Cherokee's radiator has finally bit the dust. At pretty much any speed, she stays nice n cool for about a half hour, but in the 95+ degree heat, after that, the temps start creeping up quite quickly until I shut the engine off. I've already replaced the water pump, fan clutch, and thermostat, and have tried burping the air from the engine many many times.

I've finally decided to go for a new Radiator and to convert to the Open system via a new Heater Valve and the 92+ Radiator w/ cap. However, the Radiator I'm looking at is the GDI 2 row (Advance's website says it's a 3 row, but the guy on the phone says it's 2) for $128. Are these decent radiators? The heatbuster (3 row) is $208, but I reealy don't want to spend that much on what amounts to overkill. I've also heard that the 2 rows are better simply because they don't clog as much. So what are your guys' opinions on the matter?
 
I've been hearing mixed reports lately on the GDI's, but they're not at the top of my list anyhow.

Modine, on the other hand, makes a very good radiator - I've got four of them in service.

As far as the conversion, you don't need to go to all that trouble! I've said this time and again - THERE IS NOTHING WRONG WITH THE CLOSED COOLING SYSTEM. If it's so bad, why is it on so many late-model vehicles?

The sole and only part that could be considered a "weakness" is the volume tank - which lasts quite a while (I've typically had to replace them after 10-15 years.) If you're really worried, replace it with an aftermarket aluminum tank and call it done.

I kinda like the closed system - properly maintained, it works well. With a little work, it works even better. My 88/4.0/5sp typically runs down around 185 (with no impact on tailpipe emissions, for those of you wondering,) my non-converted 89/4.0/Auto runs cooler than my converted 89/4.0/Auto (converted before I bought it,) and my 87/4.0/Auto was an ice cube.

Watch for my upcoming cooling article for details on how to improve the "open" and "closed" cooling systems, and why you won't have any trouble with either - properly maintained.

So, flush the system (before you change the radiator!) install the new radiator, and take the old one (it's copper) to the scrap metal yard to make a few bucks. Sixteen years in service - might as well change the fan clutch and water pump while yer at it. Sign and date the fan clutch - so you can keep track of when you put it in (engravers are great for this) - the average service life is about five years for those. Might want to think about a new volume tank while you're at it - you can get them from a few places - bottle and cap - for around $20. Try Quadratec (www.quadratec.com) or Morris 4x4 Center (www.morris4x4center.com) Sign and date that as well - I sign mine on the bottom with a Sharpie pen.

Signing and dating parts that are known maintenance items is a very good practise - makes it easier to keep up with what's going on. I started doing it a LONG time ago!

5-90
 
I just figure I'll switch to the open system because it's much easier to maintain, and it'll only cost me about $30 to switch over since I'm getting a new radiator regardless. I just hate having to worry about air getting into the system, and my pressure bottle, which is only 5 years old at most, is already starting to crack, a lot.

Anyway, My concern is that the GDI radiator is only a 2 row. Will it still be enough? The Modine's ($200 :( ) work great, and they're only a two row, and a Radiator shop guy told me that a two row would work great. What do you fellas think?
 
I'm very happy with my two row Modine. The Cherokee runs at 195 all the time now. The only time my electric fan comes on now is with the a/c.
 
There is no significant difference in maintenance, as far as I am concerned, between the two.

The only thing that can constitute a problem is the possibility of trapped air behind the thermostat - and that can happen to anything. The solution is simple, and I've done it to death - drill two 1/16" holes in the thermostat flange, 180* apart. Put one at the top, one at the bottom, and forget about it. You've just made the system self-bleeding.

I've seen air pockets happen with "open" and "closed" systems, so that's not a valid argument anymore. And, the problem can be made to be self-correcting, and therefore a non-problem.

The Modines I have are "high-efficiency" two-row units, meaning they're two-row radiators that think they're three-rows. I'm not sure how that works, but I got them locally for about $125 + tx, and I'm inclined to believe the performance claim. I asked for the "best radiator I could get" when I got them. If I had the part number, I'd be happy to give it to you - but I don't I really should go get it...

5-90
 
Just to make sure you know, you also have to make provisions for the electric fan to come on when you switch from open to closed system. I didnt see you mention that so I wanted to throw that out there. Like others have said, don't waste your money on a GDI, and I also agree that the closed system works just as well as the open system when operating properly.

Listen to 5-90, he knows just as much about XJs as anyone I can think of on here. :D
 
I'm going to call some local Radiator shops and see which brands they carry, and how much. But if they don't carry a modine, I'm going for the GDI for $128, I'm going to check if it rattles and for any broken fins, and plus, it has a lifetime guarantee.

Edit: I wired a switch to my electric fan, and I turn it on whenever I'm not moving for a while or I see my temps going up, and I'm planning on just putting the sensor right by the radiator hose where it's nice and hot, so I'm not too worried about that.
 
Last edited:
Atl XJ said:
Just to make sure you know, you also have to make provisions for the electric fan to come on when you switch from open to closed system. I didnt see you mention that so I wanted to throw that out there. Like others have said, don't waste your money on a GDI, and I also agree that the closed system works just as well as the open system when operating properly.
Click to expand...

Oh, for the RENIX that's easy - set a toggle switch in any convenient location. Pull two wires through the firewall (I keep 16/2 extension cord around in bulk for projects like this...) and connect the switch across the thermal fan switch in the driver's side of the radiator. Switch ON - fan ON.

The fan will still turn on if the TFS closes, or if the AC is turned on. This works because you are essentially "faking" the TFS signal - fooling the relay. You don't have to add too many components, either - that's what makes this such a nice mod for RENIX (I'm working on making it easy for later models as well...)

5-90
 
I changed over to an open system on my '89 in February. I used a 3 row radiator from "The Radiator Barn". (http://www.radiatorbarn.com/) It was $138.87 and arrived in three days. It's also an all metal radiator.

I just checked the price and it's gone down to $127.24 if ordered on-line with free shipping! Here's the link.

http://www.radiatorbarn.com/s7.asp?...submodel=ALL+MODELS&engine_size=L6,4.0L,242ci

One problem I had with the conversion was that the upper pipe on the heater core was 3/4 inch. The lower was 5/8 as expected as were all the other connection to the heater valve. I had to use a 3/4 to 5/8 adapter and a short piece of 3/4 hose to get everything together.

Also, I got a stock overflow tank from a Cherokee in the junkyard. But, I could not mount it though because the coil was mounted in it's location in the '89. So I used an aftermarket overflow tank for $10.

I've wired the electric fan to a switch under the dash for now. I only need to turn it on when I use the AC.

I've been very happy with the conversion. :)
 
One more tip, by it from a radiator shop and most will pressure test it.

You will have better luck finding one at a radiator shop anyway.
I got mine from Dave Rupples, you can find him online and he ship's all over US.
 
RyleyF said:
I'm pretty sure my 89 Cherokee's radiator has finally bit the dust. At pretty much any speed, she stays nice n cool for about a half hour, but in the 95+ degree heat, after that, the temps start creeping up quite quickly until I shut the engine off. I've already replaced the water pump, fan clutch, and thermostat, and have tried burping the air from the engine many many times.

I've finally decided to go for a new Radiator and to convert to the Open system via a new Heater Valve and the 92+ Radiator w/ cap. However, the Radiator I'm looking at is the GDI 2 row (Advance's website says it's a 3 row, but the guy on the phone says it's 2) for $128. Are these decent radiators? The heatbuster (3 row) is $208, but I reealy don't want to spend that much on what amounts to overkill. I've also heard that the 2 rows are better simply because they don't clog as much. So what are your guys' opinions on the matter?
Click to expand...

I've had my GDI 3-row for about a year now with no problems. The only time it gets a hair above the 210* mark is sitting still in 100+* heat for long red-lights. $208 is way too much for it, though. I paid $109+shipping(<$20...I think) from radiator.com.

I've seen lots of good comments on CSF too...not sure if it is 2 or 3-row. You might want to check it out too.
 
I recently got a CSF two row (metal tubes). $109 also from radiators.com free shipping, no sales tax and had it over night. Direct fit no problems...
 
I have the GDI and am very pleased with it. I might hit 210 if sitting still and A/C on. However, did the waterpump as well - FlowKooler - at the same time.
BSD
 
'93 4.0 - put a GDI 3-row in 3 years ago and this year had to get it rodded - the temp was running so high in traffic and on the highway that the electric fan was cycling on and off. The Radiator shop said it was about 35% clogged.

Don't exactly know why my system was so dirty. I paid for a Prestone flush and fill one year after the install. I'm using an anti-rust additive now.

Maybe the added capacity is overkill, but I tow and live in Texas.
 
BrianB said:
'93 4.0 - put a GDI 3-row in 3 years ago and this year had to get it rodded - the temp was running so high in traffic and on the highway that the electric fan was cycling on and off. The Radiator shop said it was about 35% clogged.

Don't exactly know why my system was so dirty. I paid for a Prestone flush and fill one year after the install. I'm using an anti-rust additive now.

Maybe the added capacity is overkill, but I tow and live in Texas.
Click to expand...
Do you have to add water often? Do you run good anti-freeze, not the pink stuff?
 
"Do you have to add water often? Do you run good anti-freeze, not the pink stuff?"

I'm pretty sure it was Prestone anti-freeze, green certainly. No leaks, no issues with adding water.

But I have concluded after this recent round of repairs and reading posts that I am going to drain what I have and go back with distilled water and the other chemicals. Maybe my city water is prone to generating lots of sediment after a time.

You know I've had cooling problems each summer since '01, with the exception of '04, so this has become sort of a ritualistic, passage from spring to summer for me and my Jeep.
 
Here I go again -


NEVER, NEVER USE TAP WATER IN A RADIATOR!

No matter where it's from, tap water will carry sediment and dissolved light metals, which deposit themselves on the interior surfaces of the cooling system. This degrades the ability of the system to transfer heat into the atmosphere, and degrades it quickly (it follows a mild exponential curve, with 10% at 1/14" buildup...)

If you have been using tap water for a while, you're going to need an acid flush to break everything loose.

After the flush, drain the block FULLY, then refill with about a 50/50 cut of antifreeze and distilled water or water filtered by the "reverse osmosis" process. RO is usually cheaper, and perfectly acceptable.

Likewise, NEVER NEVER USE TAP WATER in your battery - the buildup caused by the dissolved metals and other solids will cause internal shorts and kill batteries cellwise.

What metals are dissolved? Usually copper, tin, and iron - all from the pipes it travels around in (mostly iron.) There's a little zinc, silver, and bismuth as well - usually from the solering alloys used.

This does not account for sediment or dissolved solids that came up out of the ground with it.

I highly suggest getting one or two (plastic!) water jugs - at least 5gal each - and keeping them in the shop - or one in the truck and the other in the shop. Fill them when they get low, and NEVER put tap water in them - distilled or RO only! Do not contaminate this water!

Brian, if you've been using tap water the whole time with that radiator, it's not the radiator's fault it got clogged. Check your local water quality - you'll probably be surprised. And go get RO for your vehicle - it will save headaches.

5-90
 
5-90 said:
Here I go again -

"Brian, if you've been using tap water the whole time with that radiator, it's not the radiator's fault it got clogged. Check your local water quality - you'll probably be surprised."

THANKS for the background. I'm on board. But, as I look back, I remember the last vehicle I ever gave a flip about - '69 Fastback 351W, toploader, Chevy-eater basically ... car I kept for 17 years and never had the front end aligned, never had the trans repaired and NEVER ran with a thermostat or significant amounts of antifreeze and never had the radiator rodded or flushed.

I guess the water in South Louisiana was better than what we got here in Texas. Oh, and my Mustang started better than any other vehicle I have owned. I'm surprised Jeep owners don't all have corporal tunnel syndrome in their right wrists from cranking these pathetic, faulty-starting beasts. I love my Jeep, but it's the worse starting vehicle I have ever owned. My friend's Model-A also bumps off when it's right. I guess I know what I have to do ...
Click to expand...
 
You must log in or register to reply here.

Similar threads

S
Issues flushing dirty coolant
2
Replies
29
Views
4K
fenns7
F
M
How to choose parts and what to prioritize?! New to my XJ & wrenching.
Replies
0
Views
740
myXJpeg
M
M
New to my XJ & wrenching - How to choose parts and what to prioritize?!
2
Replies
28
Views
4K
flyin_ryan
F
K
XJ Overland build plan, need a sanity check.
Replies
16
Views
6K
jeep ride
J
M
How to choose parts and what to prioritize?! New to my XJ & wrenching.
Replies
7
Views
1K
XJI6191
X
Back
Top