TomEGun wrote:
Hi Everyone,
Just picked up a 2005 Jeep liberty CRD. I am looking forward to owning a diesel and the guy I bought it from did a lot of upgrades to it. I do have to replace the front cooling fan. It doesn't turn on when the ac is running and the temp gets between 1/2 and 3/4 on the guage when I am stopped. Once I get moving the guage goes right back to the 1/2 mark. I have herd of the over heating problems, but I am thinking that this is not the case on this one.
Tom
Hello, Tom and welcome to the LOSTJEEPS.com online forum.
You are likely correct that the front cooling fan is the cause of your overheat events when you are stopped. Did a replacement front fan cure the problem?
If not, look to see if your fan clutch has failed. Do this by going for a drive and taking along a heavy pair of gloves with you. Once the vehicle is fully warmed up and you KNOW it is hot, find a safe place to park and shut off the engine after giving the turbocharger time to cool. Pop the hood, reach down between the radiator and the engine with gloved hands and try to move the fan. If it can move without a lot of effort, then your fan clutch has failed and you will need another. WWDiesel found G.M. parts, (a fan clutch and 11 blade plastic fan), that fit exactly, cost less than the Mopar parts and are heavier duty. WWDiesel can supply the part numbers and provide a link to this topic if you ask him.
Another problem might be a clogged radiator stack; either inside the radiator OR more likely outside debris clogging the fins of the radiator, the A/C condenser or the intercooler, (or all three). Clogging inside the radiator is likely caused from using the wrong coolant or some outside contamination and will require a professional cleaning or replacement if it is bad enough. For outside debris, remove the stack, separate the three coolers and giving them a thorough wash with a garden hose or a pressure washer adjusted to a VERY light setting will take care of that problem.
Also check to see if the previous owner stuck a thermostat valve in the upper radiator hose to get the engine operating at a higher temperature. This is a VERY BAD modification and can cause serious damage to your engine down the road. It also causes overheat conditions. If there is one there, REMOVE IT!
There is a small chance your O.E. engine temperature gauge is malfunctioning and giving you inaccurate readings, (the O.E. gauge is always inaccurate, but I am talking about temperature fluctuations and readings that are way off; more so than the normal inaccuracies observed with the O.E. gauge). This could be a malfunctioning temperature sending unit. To find out, go for another drive and take along an OBDII reader and a quality, (read that as accurate), infrared temperature laser gun. Hook up the OBDII reader to the OBDII port under the steering wheel so you can get an actual temperature reading in degrees, not a needle pointing to some spot on a gauge. When the vehicle is fully warmed up, find a safe place to park and keep the engine running and take a last look at the OBDII reader. Pop the hood, grab your IR gun and shoot the laser at the bottom of the thermostat assembly. The two readings should be exactly the same or within a few degrees of each other. If the readings are far apart, (10 degrees or more), then your temperature sending unit is malfunctioning and needs to be replaced.
The least likely problem would be a worn out water pump. They have plastic impellers that wear down over time which is why the water pump is replaced when the timing belt is replaced. there is an upgrade pump that uses a bronze impeller and should last a much longer time than the O.E. spec water pump.