my 1999 with 105000 miles was feeling hot, then smelling hot, then steaming with no warning light or high temp gauge. On tear down all looks well, thermostat opens in boiling water, pump seems to spin free, and hose water will flow freely through all ports and radiator. I am replacing the plastic housing with aluminum, a new pump and thermostat and of course new fluid. I haven't found a replacement water rail in aluminum and I am not sure if I should use the old one or replace it with new plastic (mainly the gaskets that worry me).
Am I missing something?
I appreciate your thoughts as always.
Thx
MEM

 

Definitely replace that pipe. The plastic sometimes erodes and the hose pops off, or it can crack. A new temp. sender is included.

 

Remove the cover and look between the radiator and the AC condenser, there may be debris blocking airflow. I found mine loaded with junk.

 

I would be a little concerned that you did not apparently find a reason for the overheating.

 

If you still have the original water pump there is a good chance the impellor has disintegrated.

 

I live in SW FL and seldom run the heater, can I eliminate the thermostat to increase flow?
thanks again
MEM

 

You mentioned that it started to "steam", were you able to find out where the steam was coming from? Were you able to find any leaks or dripping coolant? Last month I also replaced all the plastic in my cooling system. It wasn't overheating, just more of a precaution job. I would also check your expansion and recovery tanks, and their hoses, along with your heater hoses.

Running your car without a thermostat is not a good idea. I live palm springs area where the temp is usually around 90+. When driving without a thermostat, you may notice a decrease in gas mileage or performance. This is because driving without a thermostat "tricks" your engine into thinking it is cold outside, causing it to adjust the gas mixing valve and push more fuel to the engine. Consequently, your engine can run too "rich" and performance will be affected.

 

+1 on the above. You need to identify and correct the cause of the issue.

Running an engine cooler than intended could result in other issues down the road including over fueling and more carbon fouling in various locations.

 

I will order a new water rail and thermostat, reassemble and double check for leaks. Where is the atmospheric recovery tank located? We should be together and tested mid week and will follow up with results.
THX
MEM

 

My crossover pipe failed. That's the water pipe that crosses in front of the thermostat housing. Zero warning, steam everywhere, no sign of running hot. I believe the material is micarta and it corrodes/breaks down from the inside out, you wont even notice it until it fails. I found mine online for about $36.00 (U.S, my region). Do a search on me in the forum and you will see photos of what happens. It's an easy replacement, takes under an hour depending on your mechanical abilities and tools. Nothing complicated and I think the four bolts are 8mm.

The awkward part is, believe it or not, deciding which side of the car to stand on to change the pipe...

 

all together and looking good. I found the waterpump had separated at a press fit joint and the evaporator tank cap was bad. changed all plastic parts, water rail and hoses. still have some air in system but I understand it will boil out soon.
Thanks again
Mem

 

After I finished replacing all the plastic on my cooling system, I let the car idle with the cap off, turned the heater on full blast, then squeezed the upper hose several times after the thermostat opened up. It released most of the trapped air in the system. I actually had to add additional coolant.