You have the "heavy duty" radiator. I have the same one with a winch and tranny cooler in front of it and Contour fans.She runs cool as a cucumber. I wonder if your rebuild shop put in the wrong water pump. The serpentine pump runs backwards.
Beer is the answer - it doesn't matter what the question is!
I'm having the same issues, same deal with the 8274 mounted. I run the mopar mpi.
If you change to the 3 core radiator and fan clutch you stand a good chance to put the fan clutch into the radiator core (ask me how I know).Not enough clearance.
Do you have a spring in the lower hose to keep it from collapsing?
Was your rebuild stock?
The mopar kit tends to suck a little oil into the throttle body which raises cylinder temps. any issues with that?
Do you have an overflow bottle?
Have you pressure tested your radiator cap?
Check out Novak, they have a cooling section with some good info.
but people claim the 2 core actually works better.
Where did you see that?
Originally Posted by valkadesh
I guess i could drop the $200 on the 3 core radiator, but even then i don't think my new fans will fit. I'm assuming the 3 core will have the same..or less clearance!
You probably won't need the new fans anymore. Plenty of CJ's came with 3-core radiators. If you buy the correct unit and it is all assembled correctly, there should not be an issue.
Originally Posted by valkadesh
Maybe i'd be ok with the clutch fan and the new radiator.
That's what I would expect, but I'd add a shroud. If you still want to utilize auxilliary fans after reconfiguring, you can still run them in front of the radiator. Push/pull does not matter - there is no difference. Airflow moving from the front of the radiator into the engine compartment is all that matters.
However, I would check on a few of the other things that people mentioned, such as making sure that your hoses are not sucking shut and that you do not have pressure leaks that surface once you get rolling.
--Not sure on if i have a spring in the lower hose, i kinda doubt it.
--my 258 rebuild is completely stock as far as the motor is concerned
--I do have an overflow bottle hooked up, rad cap is new (tried 2 caps to be sure)
--I'll have to check with my shop to see if they kept any record of the part number for the water pump, is there any way to tell with it installed?
I was going to get a 3 core radiator, and try hooking up the clutch fan and shroud, but it sounds like there might be clearance issues with that too.
With my 2 core in, there is a decent "gap" between the front of the radiator and the grill. I guess i just assumed the 3 core would fill that gap and leave me with similar clearance...
Clutch fans can wear out... Then the Fan does not read the temp correctly and will not "lock up" to spin the fan blades. When the Clutch Fan fails it will not pull the correct amount of air and can over heat. There is a test process in the Jeep FSM for the clutch fan. The idea is the clutch slips when you hit the gas and yields quicker rpms and more pep, but when hot the fan clutch does not slip and maxes the cooling.
The lower hose needs to have a spring installed to keep the hose from collasping. You have 2+ year old hoses so they are softer and could be sucked shut at highway speeds and higher rpm running,,,, just the wrong time to suck closed when you need cooling. For this reason, your post on hwy overheating, I think this is part of most of the issue.
The 3 core is thicker than the 2 core. I have the 3 core in a 78 and fits fine. So that could be an option for you.
Inspect the radiator.... if the top of cores are blocked with mineral deposits then there is limited water flow. This is why it is suggested you use distilled water and antifreeze in the radiator. We have hard water here in MN and every house has a watersoftner. YOU SHOULD ALWAYS use distilled water in radiators. The top of the verticle flow tubes is one of the locations the radiator likes to plug with minerals and cuts down your water/collant flow.
I have read.... The water pumps are two styles the std and the reverse flow for the serpentine belt. The inlet hose is mounted in different spots on the water pump and should be able to tell that way. Also the flow should be comming away from the top inlet hose with the cap off.
MY VOTE is your bottom hose is collasping and you may have mineral deposits. The problem in the first set up the clutch fan was worn out and not cooling properly.
Just a quick update. I drained most of the radiator last night and took a good look inside, it's really clean. I also inspected the water pump closer and found a part number stamped on the outside (31178 A) or (31176 A), it could be either a 6 or an 8 for the last number. I know my builder got the part at O'reily, but that number doesn't come up on their site or anywhere on the internet!
I guess i'll be making a trip down there to see if they are willing to open some boxes for me so i can match that part number. I'd like to ensure i've got the correct "V" style water pump on there.
If it's fine, i'm going to get the radiator checked, go ahead and replace both radiator hoses, and potentially change out the fan clutch.
The fun continues! Thanks for all the great suggestions so far!
Another update. To make a long story short, i'm pretty sure it's the correct water pump. Going to pull the radiator out tonight and get it checked, and i'll probably go ahead and replace the fan clutch and upper/lower hoses. I'll update again in a few days.
forget the clutch fan. you have a awesome electric fan to use. the three core radiators are thicker, but they are thicker towards the grill and not the engine, so clearance isnt a problem. you might have a air pocket in the cooling system that is causing the overheating problems. i have heard of this happening before and there is a way to burp the air out, but i dont know how. maybe someone who has done this before can provide some more info.
Thanks for the tips. I'd still like to get the radiator "checked" it won't be expensive. I've heard of people with the clutch fan and the 3 core (with center cap) having clearance problems with that setup. One step at a time i suppose....
Oh the rebuild has about 500 miles on it i suppose, so that may be a cause as well.
Check your exhaust for restrictions. My 5 ran really warm from the day I bought it, and I tried everything, I finally got it to stay around 220 with a 160 degree thermostat. Then when I had new exhaust installed, we found an old blown out donut gasket turned sideways and dropped down inside the exhaust pipe. Now she stays nice and cool.
fwiw from a newbie, i adjusted my timing from 1 degree btc to 5 degrees and the cooling was immediate. the dash gauge dropped from halfway in the middle from c(old) to h(ot) to a little bit above c(old) but on the red line that connects "c to h". power was much improved.