QuestionQUESTION: How Do you get to the thermostat of a Chrysler 1999 LHS? Mines keeps running hot and theres no bubbling or anything. The temp goes down really fast once I turn it off. Do you have ANY suggestions?
ANSWER: Hi Cameron,
I will assume a 3.2 or 3.5L. The thermostat housing is located close to the oil filter (above and to the left, about 10 o'clock). Here are the steps to changing it out:
Disconnect - jumper post wire (I would consider that optional)
Drain cooling system
Raise vehicle
Remove connectors from nearby oil pressure and power steering pressure switches
Remove radiator and heater hoses from thermostat housing
Remove housing bolts
Remove housing, bolts, and gasket
Clean gasket interfacing surfaces, Use new gasket, Install thermostat so bleed hole is at 12 o'clock
Tighten bolts to 105 inch-pounds
There is a special cooling filler funnel so let me know if you need info about how to use that.
It could be that your thermostat is sticking closed. It also could be a partial blockage of the radiator. Does it feel equally hot on the manifolds on either side of the the radiator?
Roland
---------- FOLLOW-UP ----------
QUESTION: Now I've replaced the thermostat, put in a new radiator, and even put in new fans. Now it runs hot randomly. The temp. gauge stays in the middle instead of under like it use to and it'll rise up and drop down and sometimes it'll run hot with the fans on. What does that mean. I have a Chrysler LHS 1999 3.5L V6
ANSWER: Hi Cameron,
So long as it doesn't boil over, the gauge going up and down is normal and reflects the expected variability of the temperature at the sensor. The fans come on when the temp reaches the point that the sensor calls for fan action, and that will normally bring the temperature, but not instantly. If you aren't loosing coolant and it never boil over and the gauge doesn't reach the full H position and stay there I would not worry about it. Randomly going hot is normal, depends upon the air temp, how fast you are moving, whether you are running the AC among other things. Did you refill it with the aid of the special filling funnel?
Roland
---------- FOLLOW-UP ----------
QUESTION: What is the special filling funnel and what does it help do? Because i didnt use one of them i just re-filled everything.
AnswerHi Cameron
The funnel (special part No. 8195) has a sidevent to release air from the pressure chamber portion of the bottle while you are filling it, and also a hose clamp to pinch off the hose that sends overflow to the rear cavity of the bottle for collection and subsequent return to the system on cooldown. The idea is to fill the pressure side and have little or no trapped air, and to have the overflow side nearly empty when you are done filling the system.
The other 'detail' involved with refilling the system after draining it or servicing the thermostat is to use the bleed valve of the engine part of the system which is located on the front upper part of the engine to allow air trapped in the system to be expelled as you add the coolant. On the 3.5 you will find that valve to be on the lower section of the intake manifold (left of center) and below the upper intake manifold. You put a 1/4" hose about 4' long on the nipple and route it out in front of the grille to a catch container, open the valve, start refilling from the pressure side of the filler bottle usind the special funnel. You keep adding coolant (and catching the overflow) until you get nothing but coolant coming out the hose which assures you that there is no more air trapped in the cooling system inside the engine. Then close the bleed valve (and remove the 1/4" hose) and continue filling via the funnel until the pressure side of the bottle is filled and to the top of the funnel. Then you remove the clip on the return line, allowing the little bit of extra in the funnel to go into the overflow chamber (the overflow chamber should not have much fluid in it). Then remove the funnel and put the pressure cap on the bottle.
Roland
So do i have to use the specialling filler funnel? Is that gonna really help?
Hi Cameron,
If you can fill the pressure side of the bottle without putting air unnecessarily into the cooling system in the process, and you remember to clamp off the return hose on the pressure/overflow bottle while you are doing it, and you use the bleeder valve and collection hose to bleed air out of the system successfully as you add coolant to the bottle per the instructions, and you end up with as little air in the system as you can, and with the level in the pressure side between min and max, and there is space in the overflow container to accept any significant expansion when the system heats up, then I would say that you don't need the funnel. So let the functioning of the system when you are finished be the answer as to whether you need the filler funnel. It may make it easier to do but it probably isn't going to be absolutely necessary.
Roland
