I have the 3 core, with shroud and fan clutch also have A/C and it runs about 190 to 195 here in Texas weather. The clearence between fan hub and radiator is 1 inch on the I-6 engine. No spring in lower hose.
Good luck in getting it solved soon.
Say what you think because those that matter don't mind and thoes that mind don't matter.
You may be right. I'll just order it up and go from there. The motor mounts are 2 months old, so i should be in great shape in that area. This whole thing has just gotten me paranoid and i want it fixed for good!
I spoke to a Jeep owning/Rock crawling radiator repair shop guy about this the other day and he told me that the lack of a spring in the hose is not an over-heating issue. He said that the only way a hose can collapse is if there's blockage somewhere else in the system. A collapsed hose is a symptom, not a cause. The only way a hose can cause a restrictive overheating problem is if it's clogged, or, it is so old and weak that it sags or kinks and restricts flow. But that would have to be a really nasty, overly soft hose.
I would look into a flushing of the entire system too. While rebuilding my 85 258, I turned the block over and ran air into the water jacket and big mounds of rust the consistancy of coarse sand blew out the ports. Probably three big handfulls. Surprised the heck out of me. All that crap had to have a negative effect on the overall temp and efficiency.
I'm really scared to take it on the interstate for any period of time. Prior to putting in the new engine, my last motor overheated on the interstate and boiled coolant everywhere!
so is this rebuilt motor doing the same, physically boiling coolant out the tube and/or into the bottle ?
are the fan blades on backwards ? pushing instead of pulling ?
hold a towel up against the grille at 2000 rpm; the suction should hold the towel against the grille.
I've seen 2 instances in 30 years where the coolant jacket where the temp sender is installed is plugged; the sender reads the cylinder head temp, ie, no water getting to the sender bulb; remove the sending unit; is water present ?
if the radiator has been checked thoroughly by a competent shop, it's not the problem; engine should stay cool with factory 2 row if everything is working properly.
It's not boiling it over, but it probably would, i'm watching my temps really close. The new fan clutch and blades suck air like crazy, that's certainly not the problem. If i loosen the sender, coolant flows out, so it's getting there too. The radiator also checked out squeaky clean, as it should be only 2 years old with limited miles on it since!
I just ordered a 3 core radiator tonight, should be in soon. I'm curious to see how the fit is!
I'm half hesitant to throw this out because of the likely pot-stirring that will occur but retarded timing will increase temps. Higher temp thermos, retarted/ported advance etc. was all part of meeting emissions requirements. I'm not saying that that's the entire problem as I don't believe it is but if your cooling system is maxed out, it sure might be the straw that broke the camels back.
I re-curved my dizzy to what the engine needed to run well, not what the engineers needed to pass emissions, went to properly set up manifold vacuum, base timed it at 8* and lower water temps were a nice little bonus to the added performance.
Are you dead-positive that your fuel and ignition curves are correct? Lean and retarded can really build up the heat. Also, I don't recall if it's been covered here but how is your exhaust? If you're running a fairly-plugged cat or restriction elsewhere, you'll likely have a lot of backpressure under a good load, like on the highway, and that won't let the cylinder clear out very well leaving nice hot exhaust in there. That can certainly escalate your issue as well.
This little heat issue has given you fits and I hope it all turns out well.
Last edited by swatson454; 08-18-2009 at 10:48 PM..
My exhaust manifolds are brand new. Cat & muffler are about 2 years old with about 3000 miles on them. My exhaust should be in excellent condition.
I haven't really played much with the curve on the distributor since i got the jeep. During the team rush, i didn't look at or change out any of the springs, and i haven't touched the allen wrench hole, where the vacuum advance plugs into the distributor.
I've probably read 50-75 thread on here on this topic, spoken to a few knowledgeable people locally, and done some other research. With that said, i'm really hoping it's the radiator not being big enough. The spiking of temperature for a few seconds when i get off the interstate seems to be a sign to some that my radiator is too small to properly displace heat.
Hopefully this will be resolved soon. It's insane (and embarrassing) that this has turned into a 50 post thread!
didnt your year jeep come stock with the serp belt? was it changed to v belt when they put on the injection possibly? reason i ask is " maybe " your pump is going in the wrong direction?? i know this was discussed prior but i would double check this. especially if a new pump was installed for that particular year jeep.
also, one thing i came across years ago was a backwards installed thermostat - if its upside down in the housing this will cause your issue.
a buddy of mine was dealing with the same issue on a v8 installed jeep and he tried everything to fix this same sort of issue. how he fixed this was drilling a 1/8th inch hole in the thermostat to burp the air.
its got to be something simple that is being overlooked.
one other thing i saw in the past was a small rag in and engine block during a rebuild that someone forgot to remove, i know its a long shot but these are some things i have come across in my years of wrenchin on stuff....
Well here is the latest. I'm stuck at the moment. I got in the 3 core radiatior from ready-rad #443583, and there is no way it'll fit with the clutch fan. I may have 1/4 inch of clearance or it may be touching. I didn't actually install it, but i measured it a few different ways. Either way it's going to be way too tight. So i can't use that with my current clutch fan setup.
I also went to replace the thermostat and cracked the housing reinstalling it. I'm waiting to get a new one it, but it's been a pain to seal even using some permatex.
I'm really beyond sick of messing with this now. I may drop it off at my shop and have them finish it up one way or another.
I'll probably try it with the fresh thermostat and give it a whirl, and if that doesn't fix it maybe try and move to a 4 blade mechanical fan with the 3 core radiator. The water pump is also a possibility still i suppose although i'm pretty sure it's got the right one.
Unfortunately, the weather has really cooled in Nashville, so it's going to be a tough comparison. 95 degree+ to upper 70s-low 80s, is a big difference.
Don't worry, i'll fix it somehow, and be sure to post updates. I hate threads that don't end with the conclusion!
If interested, I have a two row radiator I just removed from our Jeep, replaced with a three row, so I can take pictures of both to show the differences...let me know (not sure if there are already photos somewhere or not)