Just reserected a 94 Wrangler 2.5. Not runnin When I started. After electrical and minor drive repairs got her started and found temp to fluctuate. Looked inside found that prev owner dumped some sorta leak fix and gummed it all up.So? Drained and flushed with Garden hose, not pressure type.Installed New Rad, Cap,Pump,Fan Clutch,Thermo(195),Heater Core(which was filled with the gum)Both Control and Send Sensors ,All Hoses . Filled Burped and Checked system found it to come up to temp and Heat was a Blastin! For a bout a week. Was drivin one morn and found heat to be warm at best and temp was real low like 100 to maybe 130.At first thought stat failed open (safety flow type) and replaced with Mopar 195. Still same low temps. Hit various locations on unit with lazer temp . From block to hoses and all in between (this after a good highway and local run 30 mins) 80 to 105.Replaced Fan Clutch again...Still the same... Minor flow in Rad (stat not openin ) Bottom Hose cold top warm Air bound? Blocked ? I need Ideas and thanks in advance..
Make sure the radiator is full to the neck. Start the engine and let it come up to temperature. You should see coolant on top of the tubes. Then have someone accelerate to about 2500 rpm and back off, You should see the liquid drop and then come back up. It will drop typically as the water pump suckes it into the engine. then it will fill back up as the water pump pushes it up through the top radiator hose. This will tell you how well it is flowing through the system.
If you think the termostat is bad, you can do that with a cold engine. If the liquid drops in the radiator, then the tstat is not controlling the flow.
If the motor is running cold it has to be in the thermostat area.......its the only thing that regulates the heat unless the heater core is cooling everything off and I can't see how that is happening unless its bypassing the engine.???
Only other thing I can think of is make sure you have the right pump but then that would have shown up right away..??
2013 WRANGLER SPORT 2 DR., V-6 ,AUTO,HARD TOP
(Sold)1994 Jeep Wrangler 2.5L, Bestop top
/w steel half door and slider windows
5 speed, 2.5" lift, 31" tires,rack lights
Thermostats Have been Changed 3x Had 2 safety flowsWhen inspected found them to be in closed position if they fail they fail open (I by them in sets of 2 just in case) Now has a Mopar 195 ..Pump was tested and is Correct and Functioning Prop.After 30mins of drivin or sittin still runnin Does not bring temp up to operational level. Hit the block with a lazer temp and found all areas cold Top hose get luke warm at best bottom cold. open rad cap can stick my finger in forever. Cold.Hit the first fan clutch(which was new)with a timing light thought it was possibly stuck in acceleration Mode Still Cold. Next when the rain stops I'm gonna remove the clutch then the fan see if temp raises . Ive done this type of work on many other cars this one wants to be special I guess.I have heard these vehicles get air bound but wouldn't it over heat? What is frustrating is after I completed job first week up to temp and burnin Heat. Thanks for all Your Ideas and responses Guy's! Keep em comming.
You all have been Great.
Well here goes. Drained and refilled system and back filled thru heater hose. Bled. Run for 15-20-mins Low temp reading 100d to115d. next ,pulled fan and clutch assembly. Now running for 10-15-mins I get 210d Steady and perfect temp for like 2o mins. !? Runnin nice(out of warm up mode) and smooth.. Mind bogglin! Now keep in mind this is the 2 replacement of new clutch. Reinstall fan clutch assembly. Temp now sittin at 160d.Start and run .Temp drops down at 100-120 .... Hada see it for Myself I guess.Now I know what I got .looked into the clutch and it turns out that the one that this jeep and many others call for is a "Replacement Update" which For many with a high temp problems is great. Could go non themo More gas more strain and stress in higher water . End Result ??Gonna install Elec Fan . Already lookin for a host in the shop. I am that type that even if they are old I keep my Guns and Cars straight.Couldn't just block my rad (will do now) and go. Had to true it out. More work but mind resting. Thanks All for Your help. If ever I can return the favor don't hesitate ..
Will be very interesting to see what mileage you get with that engine.
From what I can figure out from the posts, the fan clutch is engaging enough that the fan blowing air over the engine is enough to cool it while it is idling. I have seen this in really cold weather with the 4cyl and having the heater on full blast. The heater core is enough to keep temp below the thermostat opening. But never seen it with the heater fan off and in moderate temp.
Since the burning fuel is the only source of heat, it indicates that the vehicle is using a lot less fuel than normal. So, will be interesting to see what you get for mileage. Please keep us posted.
Sounds like it could be a temp gauge that isn't reading correctly. You can take any thermometer that can read to 200 deg and has some kind of stem. Maybe a cooking thermometer. Tape it to the upper radiator hose where it comes out of the thermostat housing. See what temp it is working at.
Of course there are more sohpisticated ways, such as heat detector guns, etc.
At Ballistic.Yep. Was Usin a lazer Thermo thru the whole investigative process. Eveything I hit was cold.Took off the fan Assy. Ran it and temp came up to normal running levels. Hit it for temp again and all up and steady . Now partly blocked with thin duct(cardboard one side thin tin layer on other) material. Thought I had that tape in the shop but I guess someone had Ideas of their own for it's use .Temp up and cosmeticly better than plain cardboard.. Not the Correct way but gonna have to do for now anyway. Still gonna inst. electric fan ASAP. At Dawg. Interesting .When Ya did the wtr pump did Ya replace the fan clutch as recomended ? That's where I found my Problem. The New style Clutch is what I narrowed it down to ..I did all the same work listed on a 1.8 VW last year (minus the Electric fan fan ) plus head gasket and lotsa other stuff.And Down the road She went.That's what made me kinda crazy when this stuff started on such an easy to work on Vehicle. A real Pissa!