|05-16-2010 10:57 PM|
There's some basic info on the engine cooling system, including possible causes of overheating, at this site.
Lower radiator hose is the suction hose to the water pump. If it collapses, flow will be affected.
|05-16-2010 06:56 PM|
|05-16-2010 12:13 PM|
I'll try one more time.
Did you know that if 3/4 of the radiator is plugged it still won't overheat at idle?
But it will overheat driving it.
Obviously an engine idling does not make anywhere near as much heat as one running at higher speeds, and one under load will generate even more heat.
You said "flow" seems OK - what is OK? Even if the radiator is that 3/4 plugged it will still flow "OK."
What you could try is after it's cold, start and run it about 3-5 minutes, then use your hand to "feel" the radiator core - preferably while it's running - to see if it has cold spots (no flow) or hot spots.
But - you cannot reach the front to feel it due to the grill in the way, and trying to feel the back side you'll probably get your hand cut off.
The simple and easy solution?
Use that "laser thing" you scoffed at. Radiator shops usually have one, as most auto repair shops. Or you can get one yourself.
You simply aim the laser (that's the pointer so you know where you are pointing it) toward the part you want to measure and get your reading. It's easy to aim it through the grill at the radiator. Measure all around the core.
Cold or cool means it's not getting hot water circulating through that portion = plugged!
And - if that's OK, use that same thermometer to look for a plugged exhaust or CAT. A plugged exhaust will run too hot, that heat backs up into the engine. Remember, the exhaust carries most of the heat away, the cooling system only handles part of it.
The thermostat only determines the temp that coolant starts to flow.
Missimpressions that the T-stat temp has something to do with high end cooling have stemmed from when folks remove the T-stat. Then the coolant flows too fast. The T-stat is a restriction to flow. Once it's open they all pass the same amount, no matter what the rated opening temp.
But - if you use a lower than stock T-stat, on cooler days the engine will not run at the temp it's supposed to - resulting in poor mileage, carboning, fouling, oil dilution and sludging etc.
|05-16-2010 08:46 AM|
|05-16-2010 08:36 AM|
Let's hope the 195F thermostat will solve the problem but I have my doubts as the thermostat you are using now should be wide open when above 165F.
Good luck with the changeover.
|05-16-2010 08:19 AM|
Jeep wrangler over heating
Yes my jeep seems to have the same issue, mine is a 97 wrangler sport, this time of year when it's hot it seems to run past the neutral position 225 or so , I am wondering if installing a cold air intake will help?
I changed the thermostate and tried to purge the air out of the system yesterday being I had to replace the two upper coolant hoses.
I had a problem I hope I have fixed where the error code said p300 random cylinder misfire, I changed all spark plugs and wires as well as the ignition coil, thinking I fixed it will test more today.
But still makes me nervious seeing the heat guage go a tad to high,reading some of the advice on this maybe will check a few things today.
If at all possible I prefer to fix things myself being what I did yesterday the mechanic wanted 275.00 to do, and I did it for parts cost myself saveing 3/4th of that. Oh also my oil pressure guage seems to stick at times, when I first crank it says check guages because the oil pressure isnt showing, but after I rev it it moves and the light goes out, I am wondering where the oil pressure line is so I can see if its semi clogged,tell me there are two pvc elbows that come out of the top of the valve cover gasket do these just pop out? What is their porpose and should I change these, one runs into my air intake vacume hose?
|05-16-2010 07:34 AM|
This may be from "left field" and it might not even be possible, but after replacing the fan clutch, was the serpentine belt routed correctly? Could your fan be spinning backwards?
|05-15-2010 10:33 PM|
My question was supposed to be:
Why did you replace the fan? Kinda new to go south already and I wonder if there is some cause and effect happening.
Let us know how it handles the thermostat.
|05-15-2010 10:29 PM|
TJeepman I have never used stop leak or any other additive in this rig.I get great heat,and no the temp doesnt drop with the heat on.
I thought about the water pump.Havent taken it off to check it out.But at idle with the temp at 165 I get what seems to be good flow through the radiator.Hopefully the 195 thermo will correct the prob,i hope.If not the troubleshooting continues.
|05-15-2010 10:27 PM|
stevens243fan clutch is only a few months old...As for the overheating ,yes it actually overheated,just once.I just dont take it on the highway right now.Not until I get this figured out.As for city driving it runs cool.
Putting the right thermo back in tomorrow,195,see what happens.
|05-14-2010 08:50 AM|
Why is the new clutch fan? And the new one works?
If you've checked everything else it's the first place I'd start. If it's an aftermarket fan, I'd go to that immediately.
|05-14-2010 08:11 AM|
When you experienced overheating, was that just on your gage or did it actually happen? Did you try putting your heater on to bring the temperature down?
Staying cool at idle indicates there's enough air flow and coolant flow to keep the coolant temperature around the thermostat setting.
A higher temperature on the highway, assuming the thermostat is wide open, would indicate a problem with air flow or coolant flow to deal with the additional heat being generated by the engine working harder.
Sometimes a problem at the water pump, such as a broken / worn down impeller or an obstruction somewhere, can cause coolant flow to be lessened.
Then there's your radiator. Have you ever used Stop Leak or similar products in the cooling system? Is your heater putting out lots of heat?
|05-14-2010 07:55 AM|
Some people just don't have a clue.
Non-Contact Laser Thermometer
|05-14-2010 05:39 AM|
|My03Rubi||@doclouie thats pretty much exactly what the 4x4 shop told me.I feel like a total terd.|
|05-13-2010 10:14 PM|
|doclouie||You have to remember that a thermostat is there to restrict the flow of fluid so it has a chance to both pull heat from the block and cool the fluid when it is in the radiator. Heat transfer is the name of the game and can be a delicate balance between being too cool and too hot. I won't go into a thermodynamics lesson, but just because you have flow does not mean you have efficient cooling taking place. Some materials are better than others for heat transfer and plastic is not one of them.|
|05-13-2010 10:04 PM|
|My03Rubi||ya i didnt think there was any way it could be the winch.gonna give all these suggestions a shot over the weekend.well all but maybe that laser thing.will see what i can come up with...there goes my weekend thanx for the help will post results!|
|05-13-2010 10:04 PM|
|yburn||Yes go with what jpdoc say make sure you can see light throught the fins !!! I blew up a 660 grizzly atv after muding it and filling the rad. full of mud on the back side!!!|
|05-13-2010 09:19 PM|
|jpdocdave||naw, if the winch has been there that long, thats not it, and tons of people have them, that won't cause it alone. i'm more referring to dirt packed in the radiator fins. removing it is best, but i think you can just hose it out real well in the jeep and see if a bunch of dirt and crap comes out.|
|05-13-2010 09:02 PM|
Yeah, use the correct thermostat. Maybe a new one in a good idea.
Since the winch has been there 3 years, it should have acted up 3 years ago.
Stand behind it while someone revs it up. Listen to the exhaust - whistle? A plugged or partially plugged exhaust can do it. Put a vacuum gauge on manifold vacuum, rev it to 3000 unloaded. It should hold above 12 inches - if it's free.
Beg, borrow or steal a laser type thermometer - check that the radiator does not have cold spots - indicating it's plugged.
Let us know what you find.
|05-13-2010 08:32 PM|
|03 RUBI||IMO I doubt it's the winch. I have one on the front of mine and have slogged thru the desert sands when it's 95+ with no problem - the gauge stays at 210.|
|05-13-2010 07:46 PM|
ok 195 is going back in this weekend geesh i ffeel like a fool for swaping that out.shroud is in good shape and all hoses are firm.electric fan is in the plans but going to be a while.want new fan more for the extra power than anything.
i was thinking about the winch n bumper restricting airflow.dont think thats an issue.had them on for 3 years and cooling prob just started not to long ago.i am starting to wonder if maybe the old thermo was just sticking??? or maybe air pocket in system? or maybe i have absolutely no clue and am just going to try everything everyone suggests!
|05-13-2010 07:39 PM|
X3 on going back to the 195 Thermo
its what your jeep needs.
check as said by dave
I think a elec fan is a good upgrade
|05-13-2010 07:12 PM|
put the right thermostat back in, no question there. the lower t stat will not make yours overheat, but the engine and computer system need the right engine temp, but thats beside the point.
it does sound like poor air flow through the radiator. make sure the shroud is still in tact. i ripped the bottom half off on a trail before, and it will overheat without it.
second thing is clean out the radiator fins. i've seen many vehicles with dirt and crud clogging up the fins, restricting the air, and it is possible between that and the winch you are not getting enough air flow.
|05-13-2010 07:11 PM|
|Atthehop||Going to a 160 is not a cure all it does is open up earlier. The 195 is what you need to run. Look for other problems. One that most never see is the lower rad hose should have a spring in to keep it from collapsing. Swueeze it in the middle and if you can coolaspe it replace it. I would only buy OEM but that's me. There are other things but I would look there first.|
|05-13-2010 06:38 PM|
Cooling Problem - Help Please Im Desperate
Well I am new here and I really didn't want my first post to be begging for help.
But with that said I have a cooling problem in my 03 Rubi.
System was tested,pressure check, flushed and all that good stuff.Everything was said to be perfect.
Went wheeling few weeks ago and over heated.Checked everything over and could find no problems.No leaks,wp is pushing a good flow etc.
I put a bigger thermostat in,160. Now when in the city and stop and go driving it runs cold..@ 160-165.But when I get on highway and run at 60-70 mph it jumps up to about 220 or so.Gradual climb.It's acting the exact opposite of what it should be with a cooling issue,I think.
Stopped at Trails West (My local 4x4shop) today and talked with them about it.They are telling me to put a new 195 thermostat back in it see what it does.For some reason they insist I never should have put the 160 in.But it had a 195 in it when it overheated.Go figure.
Any suggestions? I thought maybe the stinger combined with the winch was blocking to much air flow but I find that hard to believe.
Before I go buying a new radiator or high flow water pump or an electric fan I hope someone could nail this down for me.
Oh ya the fan clutch is brand new as well and belt is good and tight.
Any help will be massively appreciated.