93 Wrangler running hot

[Imkunfused]

So I have a Modified 93 wrangler. Recently in the past 2-3 weeks its been running hot going up highway 50 in CA. Prior to that I had absolutely no issues of it ever running over 210 going uphill or downhill on the same highway. There have been no changes between 2 months ago with it being fine, and now. I've replaced the thermostat, coolant flush, checked the fan clutch and it's operating just fine, fan shroud is still there and is in perfect shape.

It wont heat up driving down the highway on flat ground, or driving it around town, only on a slight uphill.

I dont know the history on the radiator or waterpump as I've only put 1k miles on the jeep since purchasing it in April. The radiator appears to be in good shape, the fins are clean and untouched and it's not the orginal (meaning it was probably replaced in the past few years). There's decent flow in the radiator but I'm not tossing the idea that it could be semi-plugged. The hoses are in decent shape, and I dont believe the lower is clamping itself shut on the climb.

The only thing I could easily change would be the radiator cap, but could this really be the cause of the overheating on going uphill?

Any thoughts would be greatly appricated

Thanks

[RGRHASH]

I had that problem in my dodge...I replaced all the componets in the in the system (the pump twice) and flushed the fluid with a garden hose, except replcaing the radiator itself. The truck drove fine, but at highway speeds the temp gagewould climb into the red, turned out it was a clogged radiator...maybe that will help.

[Imkunfused]

I dont have any issues at highway speed. I can drive 75 mph all day long without breaking 210. The second I get into a 3* up-grade, the motor starts heating up, sometimes slow, sometimes fast

[rockrknockr]

i will go with RADIATOR. i have been the same route. replace everything and save the expensive part for last. ended up being the rad. this was on my dodge truck. i did the t-stat, temp sending unit, fan clutch, rad flush. still got hot, then ran cool with the new rad. it's easy to replace on a YJ, i have done it many times and maybe only $200? get a three row

[85SILVERBULLET]

f-cknn jeep cooling systems. I would try and flush the system. Go and squeeze your hoses and if they have a crunching feel you have a problem. my yj had a junk rad on it and i had a similar problem. i replaced all the hoses the rad and flushed the sytem with a hose for about 1 hour each time and i hooked it up to a flush machine twice before i got green coolant.

[Captain Ruggy]

I would also look at the water pump, I have seen the vanes inside corode away and the thing didn't leak, but it wasn't pumping much water either.

[Willys Freak]

I had a very similar, if not exactly the same, problem with the '95 XJ I had a while ago. Drove fine around town and on flat ground, but hills of any length caused it to overheat.

Prior to this I had the waterpump fail catastrophically, so when I took all the crap out to replace the pump I also replaced the t-stat, t-stat housing, and fan clutch. Matter of fact, I think the first time it overheated was the first time I took it up one of the long hills of I-15 after replacing all the other parts. Anyway, long story short, it was the radiator.

If you have someone with an IR/laser thermometer, have them check the temp of various spots around the radiator once it's fully warmed up. Cooler areas aren't getting coolant flow because they're clogged, going up hill generates a lot more heat so what flow your radiator does have isn't sufficient to cool the engine, but light loads around town or on the freeway aren't a problem.

Another really easy radiator test is to use a garden hose. Once up to temp, spray the radiator with water and notice where the water doesn't boil or turn to steam very quickly. If the water stays on part(s) of the radiator without evaporating then, as above, that part of the radiator is clogged.

Good luck.

[RGRHASH]

I dont know what transmission you have in your jeep, but I am wondering if your tranny is getting hot climbing hills and causing your radiator to work overtime???..I don't know, but that could be another area to look at...

[Imkunfused]

It's an manual so it's not affecting the heat through the radiator

[Alien Jeepers]

I have the same exact peoblem on a stock 2.5l 1998 Jeep with Automatic transmission (i know bad thing) with 31 inch trires . I could go on the freeway all day in SoCal highway 15 weather no problem , but the minute I make a u turn and start going up a grade (say the 15 freeway or going to big bear) or the grapevine or now that I live in the bay area, even going up the 680 from Milpitas/Fremont to Dublin Pleasanton and the thinhg starts going up (the needle otherwise is stuck on 211). I have replaced the waterpump twice in the last 7 years. last time was 6 months ago and had the hoses and thermostat and all that done. of course it has been cold over the winter so no problem. but lately I have been using it more and keeping an eye on the temp and when I go up hills even if I am going 35 to 45 mph on a windy livermore hill, the temp starts going up. correct me if I am wrong... on the wife's Honda pilot, you can go up the grapevine with the a/c on and going 80 and the temp stays in the middle. the jeep has no a/c but it pretty much stays on 211 unless I hit hills. My question is (i will do the temp laser check soon) does an automatic tranny really affect the temp on the radiator? I know the tranny is cooled by the radiator, but damn!?

the only other thing I blame is being a stock 4 banger it came with what 28 or 29inch tires? i bought it used with 30's and drove from the S.F. Bay Area through Arizona high Dessert, to Grand Canyon, and up to Utah Brycen Canyon and back with no problem. About a year later when I needed new tires I moved up to 31 inch tires and that is when I moved to Los Angeles (Inland Empire) and that is when I think the whole overheating thing started happening.

so if i go back to little tires do you think the problem will go away? or is it the radiator? maybe a need an aluminum radiator with 4 rows and an electric fan?


my problem is, it's not like I am the first person to put a 31 inch tire on a four banger... so any ideas? the jeep is paid off and i want to keep it but sometimes I get frustrated. i mean i got off in Pleasanton and went up an incline road going about 35 mph (it's a nice golf course and we were checking out the trees, sunday drive type thing) and I look down and there it goes again, between the 210 mark and the 260 mark... man! so I made a uturn and went back down hill and it went back to normal in about 5 to 7 minutes.

thanks and sorry about the rambling. I am just frustrated.

Gus.

[Imkunfused]

I ended up replacing the radiator in mine not long after my last post and my overheating problem went away. You shouldnt need to bump up to a aluminum or a 4 row. My problem was the fact that the lower part of the radiator was plugged up. The new radiator was a 1/2" thicker, all metal like my last one, but weighed a few lbs less due to not being plugged up.

[Willys Freak]

Originally Posted by Alien Jeepers

I have the same exact peoblem on a stock 2.5l 1998 Jeep with Automatic transmission

If it's the original radiator (Now 10+ years old) without regular flushes then it's time to replace that bad boy. A clogged radiator works like a small radiator, your cooling capacity isn't completely gone but it is reduced. Driving around flat ground or small hills doesn't exceed what cooling capacity is left in the radiator, but on long climbs it just can't keep up and your engine temp creeps up.

[Alien Jeepers]

Thanks! did you do your own? where did you buy it? and if you don't mind, how much does that cost? I now live in an apartment building so I cannot do it myself.


Thanks again! makes me feel better.

[Willys Freak]

Originally Posted by Alien Jeepers

Thanks! did you do your own? where did you buy it? and if you don't mind, how much does that cost? I now live in an apartment building so I cannot do it myself.


Thanks again! makes me feel better.

Yeah, I did my own though this was in an XJ (More of a pain), I couldn't locate an all-metal unit locally and it was my DD so I picked one up from Kragen, I think it ran about $180. Since you can't do it yourself I'd suspect it'd take a shop 2 hours (2 x $90/hr = $180).

No friends with a driveway or garage you can use?