overheating at freeway speeds issue still not solved!!!

[AZRockRunner]

OK, I have a 90 XJ with almost 300,000 miles and still going strong. I can crawl all day in 100 degree heat and its fine, BUT it gets almost to redline hot at freeway speeds. I have nothing to gauge on as it was not running before when I got it and I immediatly did the 3 core rad and uper/lower hoses and T-stat change.
I have read alot of articles about this but to no resolve.
So, can anyone tell me if this problem has actually been solved? Without throwing a guess. I am tired of throwing parts at a problem and not fixing it.

Thanks in advance.

Brian

[old_man]

The classic cause in this instance might be a lower radiator hose that is collapsing. The OEM hoses had a spring inside to prevent this. A good parts hose will have a spring you can insert.

[rockwerks]

OK, I have a 90 XJ with almost 300,000 miles and still going strong. I can crawl all day in 100 degree heat and its fine, BUT it gets almost to redline hot at freeway speeds. I have nothing to gauge on as it was not running before when I got it and I immediatly did the 3 core rad and uper/lower hoses and T-stat change.
I have read alot of articles about this but to no resolve.
So, can anyone tell me if this problem has actually been solved? Without throwing a guess. I am tired of throwing parts at a problem and not fixing it.

Thanks in advance.

Brian

what is your gearing and tire size? how is your electric fan working? what temp to T-stat? which 3 core radiator?

[AZXJ]

How's the fan clutch..?? Most cases of overheating at speed indicated the fan clutch is failing.

Dave

[AZRockRunner]

I will try to answer all:
Gearing is 4:10 and running 33's
Replaced upped and lower hoses and yes it has the spring in the lower one.
Electric fan is new one from a 99 got from dealer when doing the swap.
Fan clutch works fine as it fully kicks in when idleing and what not.
Also, I was not aware that the fan clutch or electric fan made any difference when running at freeway speeds.
If I open the hood and idle that thing for 10 minutes, it cools right down and will crawl all day at below 205 200.

The only other thing I can say is that when it was really hot, the overflow bottle was EXTREMELY full and when it finally cooled down, it went back to normal levels.
Kinda makes me think that the T-stat may not be working properly, but like I said before, All is replaced and I dont want to just throw parts at it. I was hoping someone had the same problem and resolved it.

Thanks for all the replies.

Brian

[old_man]

Do a sparkplug reading and see if you are running too lean. Make sure your ping sensor is connected and working.

[rockwerks]

what temp of T stat? stock or 180*

[AZRockRunner]

Checked plugs when i tuned it up last year and it just passed emissions with flying colors.
T-stat is a OEM 195 replacement.

[rockwerks]

well then if its nothing in the cooling system, then its something else. like ring blow by, you would not notice it crawling but under higher revs it would heat up the motor. I do have an 68,990 mile 89 xj motor sitting up here in flagstaff waiting for a new home.....................400.00 and its all yours

[Winks00XJ]

Just a guess, if the T-stat was stuck open then the coolant wouldnt stay in the radiator long enough to cool down properly when at freeway speeds. When going slower the pump turns slower therefore the coolant would be going thru the radiator slower and having a chance to cool more. Just a guess. Another thing for cooling properties, make sure you are 50/50 with water and coolant.

[AZRockRunner]

well then if its nothing in the cooling system, then its something else. like ring blow by, you would not notice it crawling but under higher revs it would heat up the motor. I do have an 68,990 mile 89 xj motor sitting up here in flagstaff waiting for a new home.....................400.00 and its all yours

PM Sent to u Rockwerks.

Winky, i thought about that to. it is a valid point for sure.

[rockwerks]

PM Sent to u Rockwerks.



I got no PM's

[MOBILEJEEPCLUB]

if it had water in it alot the impellers in the water pump rot so the faster it turns the less water it moves happens alot down south where i am also caused from tap water with a high calcium content .

other possibillity is combustion leaking into the cooling system at the head

i suggest a new water pump and a compression check

[Wounded XJ]

Mine was overheating at highway and at low speeds about two years ago. Put in a Flow Kooler water pump and a lower T-stat, 180 or something. At this time I flushed my system and had a 50/50 mix. It ran so cool I lost my heater and had to go back to the stock T-stat. Has been running great since.

[AzFlexJ]

hey brian...the above comment on the water pump would be my guess too....az water has a lot of composts in it and eats up cooling systems...i saw it a lot when i worked for jim click ford.

[xjnco]

Do you have all of the fan shroud in place? Replaced mine last year because I cracked it while pulling the tranny, and a large chunk broke away. It does make a difference.

Mike
xjnco

[AZRockRunner]

Do you have all of the fan shroud in place? Replaced mine last year because I cracked it while pulling the tranny, and a large chunk broke away. It does make a difference.

Mike
xjnco
Shroud replaced when I did radiator. I got over anxious and BWOKE IT!!!!!

I am going to try and replace the Water pump and T-stat before Saturday. But I also got to get my removable doors done, so it might have to wait till next week.

[TUFFXJ]

I think its just a piece O junk....you need a BFF in the hood and all your problems will be solved..and if not it looks cool anyways:spin3:.....

[AZRockRunner]

I think its just a piece O junk....you need a BFF in the hood and all your problems will be solved..and if not it looks cool anyways:spin3:.....

HMMMM, Why dont you trouble me for a WARM GLASS OF SHUT THE HELL UP??????? Saffard boy!!!

[AZRockRunner]

UPDATE!!!!!!!
I believe I found the issue. This last weekend while doing a run, it started overheating at any higher revs of the motor. By the time I got home, we had the heater on full blast just to keep the temps under control. I took apart everything to check the water pump and the pully is EXTREMELY loose and sloppy. So, I found the source of my bearing noise as well as the over heating issue. The bearings are shot in the water pump.!!!!!!!

So, just ordered a brand new Hesco unit with the balanced T-stat and high flow T-stat housing. I should have it by Friday and will install it this weekend.

Lata

[Wounded XJ]

I hate being right all the time. :smoker:

[AZRockRunner]

I hate being right all the time. :smoker:

:eek: I think I just threw up in my mouth and swallowed it. NAAAASTY!!!!!!!

Dont get to cocky, or you will have to sell your XJ and buy a Wrangler!!!!!

[Wounded XJ]

You tossed your lunch in your mouth! Mission accomplished:yelclap:

[AZRockRunner]

well, heres to resurecting an old but yet still unsolved thread.
it is still overheating at speeds. I now have 2 T-stat sensors in there. The stock one in the rear of the block and a autometer one in the new t-stat housing. The block one reads about 220 - 225 and the autometer one reads 240ish at highway speeds. I will assume that the new autometer gauge is more accurate as it takes it reading from the t-stat housing.
So, I am going to snag a compression gauge from JJ next weekend I think and check that. Weird thing is that I dont use much oil at all between oil changes. were talking maybe a 10th of a quart. My only other concern is that my oil pressure is low. It will be normal when I 1st change it using diesel oil but drops and stays at 1/4 after a few miles and pretty much stays there unless cold.
So, I am thinking that maybe the motor is just getting tired. I dunno, but I really need to get this fixed couse I got alot of $$ into this damn thing and really dont wanna start all over with another jeep. Unless I could find a nice running 2 door auto to swap everything over to. LOL

[AZRockRunner]

just another note. I have a cheap non contact thermometer from HF. it is pretty accurate. I placed that SUPER close to the upper rad hose and it is saying 205 degrees. The gauges on the dash are both stating over 220 right now. Is it possable I dont have an overheating issue, just bad gauges? I mean that would be weird to have a brand new autometer gauge reading bad and the factory one also but hey, stranger things have happened. So, is there a dead on accurate way to test water temp?

[azdesertrhino]

I've got a couple of very accurate electronic digital thermometers I use for work. Give me a call tomorrow and if our schedules allow we'll hook up and get some accurate measurements.

Shooting the hose may not give a true reading. The rubber acts somewhat as an insulator.

[AZRockRunner]

will do Jimbo.
Thanks

[AZXJ]

Fan clutch ?? :wierd:

[AZRockRunner]

Fan clutch is brand new. And it does lock up at idle when warm and spins loosely at higher RPM.

[sjkimmel99]

Is your Autometer a mechanical or electrical gauge? I added a mechanical water temp because I didn't believe the dash gauge. The sensor goes in an in-line upper hose adapter so the water should be as hot as it's going to get. The mechanical one reads around 20 degrees cooler than the electrical one in my case.


When you measure the temp with the no-contact thermometer check the passenger side tank on the radiator and the drivers side to see what the temp drop is across the radiator. That won't tell you what it is at highway speed but should give you an idea of what the efficiency is of the radiator.

Also try Water Wetter or Purple Ice additive. You'll need to think down the anti-freeze / water mix to less Anti-Freeze for best results.

If your thermostat is a Stant or similar spring activated consider switching to the Mr. Gasket (similar or same as Robert Shaw.) Can be found here and a few (but not many) other places.
http://store.summitracing.com/egnsearch.asp?N=700+115+302860&D=302860

[AZRockRunner]

AzDesertRino and I are going to measure the temp one day this week with contact and non contact gauges. I added a electrical temp gauge but have since been told that a mechanical gauge is alot more accurate. I will look for a mechanical one and order that A.S.A.P.
Also, the thermostat is the one that Hesco sends with there high flow kits.

Now a question, will the mechanical gauge fitting go into the thermostat housing like the electrical one does, or somewhere else?
The reason I ask is that the " HIGH FLOW " thermostat housing they sent did not seem to have as much flow as the RENIX one I took off there. I mean it was purdy and polished andlarger that an HO one, but not the same as the renix one.

As far as water wetter goes, I am using some that I got from checker. Didnt seem to do as much as I thought it would.

Thanks
Brian

[AZXJ]

When was the last time you cleaned the bugs outta the front of that pile ?


:D

[sjkimmel99]

I don't know which t-stat Hesco sends. If it doesn't look like the one at the Summit link it's not the same.

The mechanical probe is a lot bigger than the electrical one.
I added the mechanical temp probe using an adapter that goes in-line in the upper radiator hose. I got the adapter here:
http://www.jazzproparts.com/product_p/gs-bw07-r.htm
The 1 and 3/16 size seems to work well. If you go this route you'll need to drill out the existing 1/4" hole and tap the hole to fit the mechanical probe.

If you get an Autometer gauge order this adapter separately: 2263 (or AMT-2263 from Summit.) It accepts the 5/8-18 UNF threads of the probe and has 3/8 NPT male threads which is what you'll have to drill and tap into the in-line hose adapter (or anywhere else.) Otherwise you'll have to find room for a 1/2 NPT hole to use the adapter that comes with the gauge. With either adapter the probe sticks about 1/2" into the passage which seems plenty and doesn't appear to block flow to any noticable degree.

I got the temp gauge from Summit, an AMT-3331 for what that's worth but you can get both the gauges and the adapter (although it's a special order item, 1-2 days) from Checker and trade the Summit "handling" charge for AZ sales tax.

If I was to do it again I'd use the "non-AC" upper radiator hose which would avoid having to piece together a hose from bits and pieces and possibly even the wood support.

http://farm2.static.flickr.com/1027/539941924_8b1e49c6fe_o.jpg

[AZXJ]

That's alot of parts.. After he spends his wad on all that, he's gonna still need a new Radiator.. :banghead:

[AZRockRunner]

I will probably order the mechanical gauges like yours and use it in the T-stat housing. I will wait until Jim and I test the rad for cold spots.
As far as cleaning the bugs from the front of my PILE!!!! Spotless man. As you will soon see, my rig might have 302,xxx miles and counting, I may have had it on its side once or twice, and it might have a rustolium paintjob, but I am VERY PARTICULAR about cleaning my rig from bumper to bumper after EVERY run. Yes Dave, that includes the radiator. LOLOLOL :sure:

I was also looking at some other threads and I am thinking that the $100 Generic 3 row radiator I got in there might have been a bad choice. The water channels are extremely small and could clog really easy. I was thinking about a single core aluminum???

[AZXJ]

:banghead: Shuda went hawks !! :wave1: When ever you finger it out and need some real parts let me know.. :rof:

[AZRockRunner]

Well I WANT long arms, but cant afford right now. LOL
I need to get this damn overheating things SOLVED once and for all. Otherwise Iwill end up like Dave........... BALD AND CRAZY!!!!!!!
:anon: :bawl: :bawl: :bawl:

[AZXJ]

BALD AND CRAZY GETS ME LAID !!! :D

[AZRockRunner]

TMI TMI TMI. DAMMIT DAVE, that is NOT a vision I EVER wanted in my head!!!!!!!!!!!!!!!!!

Hasta

[AZRockRunner]

Well thanks to fellow XJ'r rockwerks my overheating problem will be solved. I purchased a SUPER low mile Renix motor from him that will get swapped into my Heep. I think he said it had around 69 or 89 k on it. All I know is that is looks nice and clean. I will be posting pics of the clean up and swap just for grins and giggles.
I will be installing 2000 Exhaust manifolds since I got them for free and they will flow better than stock and never crack. Also a new oil pan, rear main seal and oil pan gasket, and distributer while it is out. I hope to have it installed and back on the road in a few weeks depending on my work schedule.
Thanks to all that replied to this thread in attempts to resolve the overheating issue. It appears that 302,xxx miles is about the limit for the renix.

Lata
:thumbup:

[Wounded XJ]

Well thanks to fellow XJ'r rockwerks my overheating problem will be solved. I purchased a SUPER low mile Renix motor from him that will get swapped into my Heep. I think he said it had around 69 or 89 k on it. All I know is that is looks nice and clean. I will be posting pics of the clean up and swap just for grins and giggles.
I will be installing 2000 Exhaust manifolds since I got them for free and they will flow better than stock and never crack. Also a new oil pan, rear main seal and oil pan gasket, and distributer while it is out. I hope to have it installed and back on the road in a few weeks depending on my work schedule.
Thanks to all that replied to this thread in attempts to resolve the overheating issue. It appears that 302,xxx miles is about the limit for the renix.

Lata
:thumbup:

What I am I, chop liver? Good talking with you guys today!

[AZRockRunner]

What I am I, chop liver? Good talking with you guys today!

Why yes, actually you are chopped liver!!!
Just kidding!!!!!!!

Thanks to Jon for transporting this engine to Casa Grand where we met up with him and picked it up from him and delivered his new auto trannie and T-case.

And I must take this opportunity to once again be thankful that I am involved with NAXJA. The naxja community has once again stepped up and made things happen.

So, Thanks again to Brian and Jon and JJ for doing whatever was needed to make things flow like they did.

:guitar: