I'm Gonna Slash - Overheating Saga - Yes, Still!!!

[ParadiseMJ]

Don't know who has followed my overheat saga, more like an odyssey!!

 

http://comancheclub.com/topic/38373-road-trip-a-little-hot/page-4

 

...so here's the deal...

 

I've been driving the Jeep over hill and over dale, pushing the ferk out of it for the last 2 weeks to shake it down for my upcoming Jackson Hole trip.  Well, it's done great, running just under 210 under some adverse conditions.  Towing a small but heavy trailer, wheeling up a steep slow n' go 15 mile dirt road, blasting around town, sitting in traffic, extended idling.  No sweat.  Absolutely NO hot temps.

 

So today I decided to take it to work.  22 miles, 18 miles of it highway speed and FLAT.  It was cool here this morning and the first 4 miles is all downhill.  So, about 3 miles before I got there, the needle started climbing...

 

Fast forward to the ride home...10 miles (on the flat) at 65 the needle started going up.  By the time I got half way up the hill, I'm at the red.  Pulled over, boiling over, towed home.

 

My OWN advice has always been:

 

Overheating at idle or slow n' go is an AIR FLOW problem (either a bad fan clutch or restricted air flow)

Overheating at speed is a coolant flow problem (either a clogged radiator or a bad pump)

 

I has discounted both of these since all the parts are relatively new (miles wise).  I still don't think my water pump vanes are corroded, and the coolant has always been clean as a whistle.

 

WHAT SHOULD I DO??

[JeepcoMJ]

overheating on the flat at a certain speed sounds like fluid cavitation to me. Double check to be sure you put the correct water pump in, if you ever replaced it. The rotation is different between different years of xj/mj/zj/tj

[MJCARENA]

I would check the thermostat first. Might not be opening all the way. I had the same issue, just one day it started to run hot. Just replace and go from there.

[Exgrayxj]

Yes, I have been following it closely- I am having the same problem.

Had heating problems previously, thought they were cured, had gotten to the point I dared to drive without one eye on the temp gauge.

It's been nearly a year.

The other day, started to run hotter again.

 

Though I didn't do it, the pump is fairly new, still shiny, and I have coolant flow.

Fan clutch replaced previously.

Thermostat new, but pulled it and checked again.

Hoses good, no collapse/suck shut.

 

This weekend replaced the radiator with a brand new one.

Pulled and checked the fan clutch again.

All shrouds in place.

Later style electric fan (s blade).

Bled the head at the temp sender.

Converted to open system.

 

Still slowly gains temp, going down the road.

If I manually turn on the aux fan, it will bring the temp down to around 210 (dash gauge).

No coolant loss, no steam/antifreeze smell from tailpipe.

Flush cap at the highest point in my heater hose for secondary bleed point, and to check for full.

 

Not trying to hijack, just needed to vent.

 

Can I borrow your cliff?

 

[mpace6a]

I was going to suggest the cat. converter, but seems you've gotten that already. I know it seems trivial to even suggest at this point, but, I kept having issues with my dads '97 ram, had to put 4 or 5 different thermostat's in it, before the last one finally fixed it. don't know why, the others opened fine when tested, but would just stop opening after being in the truck for a week or so. Plus, its the cheapest thing you can do to test your system.

[cruiser54]

Perhaps all the good coolant should be drained and saved.

 

Then, remove the CTS from the side of the block and flush the block.

 

I had a Renix with a ton of rust accumulated down there and only got it out by "pulling the plug". It didn't circulate during normal operation. It just sat there.

[1989 Eliminator]

I didnt see anything about a new water pump in your fourm. Bad, wore out propeller blades would not circulate the fluid as well which could make it over heat. How old is your pump?

 

 

Perhaps all the good coolant should be drained and saved.

 

Then, remove the CTS from the side of the block and flush the block.

 

I had a Renix with a ton of rust accumulated down there and only got it out by "pulling the plug". It didn't circulate during normal operation. It just sat there.

 

Crusier, how the heck do you get that plug out?!?!? It is not a simple 3/8 drive extension. I found that the plug is actully a 5/16 square. I took a 3/8 extension and ground down the square end till it fit in the plug. I have never heard of any socket or anything that has a 5/16 square.

[ParadiseMJ]

As I said the water pump is only 2K miles old...but...it's been in there for 3-4 years.  It's actually the first thing I'll be looking at, since it's the easiest to remove.

 

As far as the question on how to get the plug out...it's not 3/8" and it's not 5/16".  I ground down a sacrificial rachet extension, until it fit.  I tried the extension by itself, too big,  I tried some 5/16" square stock, too small.

[HOrnbrod]

The drain plug on my 91 is a recessed 8mm plug. I have a combination metric plug tool that I used on Benz's that fits it fine. 8mm square stock will work too. Or you can also get a socket or grind down a 3/8" ratchet extension. If you get it out be sure to use anti-seize when re-installing.

 

BTW, when I pulled mine, practically no junk came out.

[ParadiseMJ]

BTW, when I pulled mine, practically no junk came out.

 

I have yet to find any junk, crud, crap, chunks, sludge or anything else that should not be in the engine, pumpkins, cooling system or tranny...anywhere that one would normally find said goo on a 25 yr. old truck.  I guess that's the beauty of regular maintenance.

 

Just some of the pictures I see of "other guys" rigs make me anal about it.  Not that it's helping me any.

[Zebvance]

ooohhhhh this sucks to hear you are still having problems. I don't know what else to tell you besides start replacing new components....... like the radiator is where I would start.. maybe a CFS 3 row...

[1989 Eliminator]

Yeah sorry to repeat yourself but I didnt see anywhere latly saying how old the pump is. Your pump should be fine then. Here is a side note to that though... I just replaced my water pump and in the lower radiator hose there was a spring. This is to keep that hose from collasping. My spring was all rusty and falling apart so I just got a new hose and put it on the new pump with no spring inside. Now, I havent had any issues yet. BUT, if you do not have a spring inside your hose then your hose could be collasping and causing a huge restrication. Check that out.

[ParadiseMJ]

I have a new hose WITH a used, but newish condition spring I got from a member here 2 mos. ago..  No corrosion anywhere I can find 

 

what I really need is Voodoo!!

[1989 Eliminator]

hm. okay. I tried!! and I'm guessing you had a hard time finding a spring.... awesome. I'm in the process of finding one.

[cruiser54]

I didnt see anything about a new water pump in your fourm. Bad, wore out propeller blades would not circulate the fluid as well which could make it over heat. How old is your pump?

 

 

Perhaps all the good coolant should be drained and saved.

 

Then, remove the CTS from the side of the block and flush the block.

 

I had a Renix with a ton of rust accumulated down there and only got it out by "pulling the plug". It didn't circulate during normal operation. It just sat there.

 

Crusier, how the heck do you get that plug out?!?!? It is not a simple 3/8 drive extension. I found that the plug is actully a 5/16 square. I took a 3/8 extension and ground down the square end till it fit in the plug. I have never heard of any socket or anything that has a 5/16 square.

 

Don't pull the plug. Pull the CTS. It's in the same coolant galley.

[ParadiseMJ]

I have a hex head in the block drain, I've had it out before. Might pull them both.

 

I'm puttin' this to bed for the rest of the week.  Going camping for 5 days without my truck.    :fs1:

 

Thanks for the suggestions, be back in a few days.

 

[1989 Eliminator]

 

I didnt see anything about a new water pump in your fourm. Bad, wore out propeller blades would not circulate the fluid as well which could make it over heat. How old is your pump?

 

 

Perhaps all the good coolant should be drained and saved.

 

Then, remove the CTS from the side of the block and flush the block.

 

I had a Renix with a ton of rust accumulated down there and only got it out by "pulling the plug". It didn't circulate during normal operation. It just sat there.

 

Crusier, how the heck do you get that plug out?!?!? It is not a simple 3/8 drive extension. I found that the plug is actully a 5/16 square. I took a 3/8 extension and ground down the square end till it fit in the plug. I have never heard of any socket or anything that has a 5/16 square.

 

Don't pull the plug. Pull the CTS. It's in the same coolant galley.

 

That is the temperature sensor right next to the plug correct? just to the left of the plug on the exhaust manifold side of the engine? If that is what you are talking about I did pull that sensor out before and when I did there was solid metal behind the sensor. No fluid came out. Should it be an open hole?!?

[cruiser54]

 

 

I didnt see anything about a new water pump in your fourm. Bad, wore out propeller blades would not circulate the fluid as well which could make it over heat. How old is your pump?

 

 

Perhaps all the good coolant should be drained and saved.

 

Then, remove the CTS from the side of the block and flush the block.

 

I had a Renix with a ton of rust accumulated down there and only got it out by "pulling the plug". It didn't circulate during normal operation. It just sat there.

 

Crusier, how the heck do you get that plug out?!?!? It is not a simple 3/8 drive extension. I found that the plug is actully a 5/16 square. I took a 3/8 extension and ground down the square end till it fit in the plug. I have never heard of any socket or anything that has a 5/16 square.

 

Don't pull the plug. Pull the CTS. It's in the same coolant galley.

 

That is the temperature sensor right next to the plug correct? just to the left of the plug on the exhaust manifold side of the engine? If that is what you are talking about I did pull that sensor out before and when I did there was solid metal behind the sensor. No fluid came out. Should it be an open hole?!?

You pulled the knock sensor.

 

The CTS sits higher up in the block and has an electrical pigtail on it.

[1989 Eliminator]

Okay thats what I thought... I didnt notice another sensor above the plug. With it being higher though, not much crude (if there is any) would flow out of the block.

[cruiser54]

Okay thats what I thought... I didnt notice another sensor above the plug. With it being higher though, not much crude (if there is any) would flow out of the block.

Yes, it will!! It's where it can all settle around the cylinder walls. Believe me, I've had these engines apart. Pull the CTS and run some water through the block after it has draind to flush it out. You can use a hose into the thermostat housing with the stat removed.

[1989 Eliminator]

Hm, I just thought with it being higher up that the sediment would settle at the lowest point, but I guess it still would still come out with flowing water going through the block. I've been wanting to do this so bad but I could never get that darn plug out! Good to know the CTS will also work. Thats going to make a good mess of things for sure!

[cruiser54]

Hm, I just thought with it being higher up that the sediment would settle at the lowest point, but I guess it still would still come out with flowing water going through the block. I've been wanting to do this so bad but I could never get that darn plug out! Good to know the CTS will also work. Thats going to make a good mess of things for sure!

Where the CTS is, is the lowest point of coolant in the block.

[ParadiseMJ]

OK, so I removed the water pump...here's what it looks like.

 

 

Looks like there's "water line", one side of the line is nice n' clean...the other side of the line is crusty.  The crusty part does not look like anything inside the engine, which is clean behind the pump.  There is no sludge, rust or calcification around the cylinder walls.

 

Also I know that the coolant has not been 2/3 empty as the water line might indicate as it's been up to the tippy top and burped.  Even though the pump turns, it's the correct rotation, and it's been full of coolant almost constantly, the vanes are solid, the bearing is not wobbly, it's not weeping.  Is this cause to think it wasn't working properly (e.g. cavitating)??

 

...AND is it likely that the inside of my radiator looks like the crusty part (it's a 2-3 yr. old 2 row all metal CSF with ~3K miles on it).

[jimoshel]

Had a Chevy engine with a over heating problem a couple years back. Nothing helped. Chemicals, flush, etc.. Popped out all 4 freeze plugs. The back 3 were filled with rust and sediment completely covering the hole. The front one had maybe a 3/8 gap between the top of the crud and the top of the hole. A couple minutes spent with a piece of wire and a vacuum cleaner cleared it up. Just saying.

[cruiser54]

Had a Chevy engine with a over heating problem a couple years back. Nothing helped. Chemicals, flush, etc.. Popped out all 4 freeze plugs. The back 3 were filled with rust and sediment completely covering the hole. The front one had maybe a 3/8 gap between the top of the crud and the top of the hole. A couple minutes spent with a piece of wire and a vacuum cleaner cleared it up. Just saying.

That's what I was thinking. Good time to pull the CTS and flush water through the waterpump opening.