Author Topic: Could my water pump be broken? (Read 5589 times)

rallydiesel · « **on:** April 21, 2007, 04:24:00 pm »

My car tends to overheat gradually if left standing at idle. I tested the fan and it works but I have never seen/heard it come on, even at high temps. I replaced the thermoswitch and that didn't help. I know the thermostat works to some degree because I can feel the radiator get hot at a certain temp. Eventually the coolant starts to steam out of the reservoir.

Could my water pump be trashed? I haven't taken off the v belt yet to play with it but I can't see what else it would be. Is there any way to tell if the water pump is screwed? If I drive around then the temp stays relatively normal. Is there anything else that affects the fan like a fuse or something? Again, I have tested the fan wire with a jumper and power does go to the fan and the fan runs fine when power is applied directly to it.

:?:

rallydiesel · « **Reply #1 on:** April 21, 2007, 05:51:12 pm »

I'm starting to think this is due to the A/C. There is a lot of interconnection between the A/C and the fan. Maybe something is burnt out and preventing the fan from turning on. There is some sort of relay just above the fan that has the fan's power supply going into it.

jtanguay · « **Reply #2 on:** April 21, 2007, 08:06:27 pm »

i would suspect a faulty relay.

my water pump pulley seems to be slipping at high rpm (overheats on the highway, and sometimes in town :twisted:)

never let the coolant boil over though... at idle she keeps her temp perfectly, and the coolant fan kicks right on! also the t-stat opens perfectly at 87C

all of my wiring for my fan (and the fan itself) died.. i blame a/c! they are very prone to having issues due to the fact that the rad fan has a super high speed mode (on a nice hot day if it was on for long enough, it could slowly burn out the motor, and corrode the wires, or even blow the relay like on mine!)

best idea, is to just take out the thermoswitch connector (drivers side of the rad, bottom portion) and then there should be 3 connectors. take a wire and jump two at a time. the fan should kick on both high and low speeds depending on which ones you jump (only jump each side with the center wire... i hold no responsibility if you jump both outside wires... i have never tried it, and don't think it would hurt anything, but just a warning)

now if your fan doesn't kick on, then bingo! if your rad fan does kick on, then suspect the thermoswitch as faulty. i replaced mine with an acdelco i think... i don't think brand is as crucial as the t-stat. best part about changing that, is that if you do it fast enough, you won't lose too much coolant :lol: .

i will be changing my belt soon... probably tomorrow. it only has about 45 degrees of belt coverage, so that makes it a good candidate for some bad slippage at high rpm!

Good luck!!!

edit: forgot to mention... there is an a/c resistor located on top of the fan motor... you can't really miss it. mine was blown... had to replace it. it is for the a/c low speed. without this resistor, your a/c will overheat and cook itself real good, and all the gas will blow out one of the expanded o-rings (probably the one going from the compressor to the condensor... ask me how i know this :lol: )

so if you're keeping a/c, get everything fixed asap :wink:

rallydiesel · « **Reply #3 on:** April 21, 2007, 08:46:24 pm »

The A/C doesn't work. I really don't want it. Is there a guide to removing the A/C? I will keep the compressor so I don't have to change the alternator position. I would like to get rid of all the A/C hoses and annoying wiring.

A strange thing happened tonight. I went to double check the fan and now it wouldn't come on when I jumped the thermoswitch! It worked this morning! I checked the 30 amp fuse and it is not blown. I have no idea now. I just want to rip out all this stupid A/C wiring and have nice and simple wiring.

jtanguay · « **Reply #4 on:** April 21, 2007, 09:24:14 pm »

just rip all the a/c hoses off. the wiring isn't crucial, but you can disable the low speed & clutch by cutting power, or just simply removing the a/c relay (easier) to make sure that it doesn't get turned on accidently and burn out a belt...

sounds to me like the same thing that was happening before my fan quit on me. it worked intermittently, and then i had to 'kick' start it with my hand (carefully of course). by this point i had my a/c on full with a charge of that eco friendly stuff... it got real nice and cold! fan was hooked directly to the battery.. that might be what finally killed it, but oh well! ran for 2 mins before just quitting... probably just an internal contact! very robust fans.

my suggestion: go get a used fan and swap it out... take out the condensor as well (this will give much better cooling in the summer around town)

if you keep the a/c hoses intact, you may be able to re-sell them to someone who's looking for a specific hose... a buck is a buck :wink:

jimfoo · « **Reply #5 on:** April 21, 2007, 10:10:53 pm »

The a/c condenser would probably make a nice oil cooler :wink:

jtanguay · « **Reply #6 on:** April 22, 2007, 01:22:11 pm »

Quote from: "jimfoo"

The a/c condenser would probably make a nice oil cooler :wink:

you might be on to something there... although old corroded a/c refrigerant turns very acidic and starts to eat the the condensor from the inside :shock: if the system was previously charged, then it probably hasn't started to pit much... mine has pitting on the lines, and a little bit of rust, but it still cools...

has to hold 300 psi or so of pretty hot gases, so i'm guessing it would be able to handle the oil no problems

rallydiesel · « **Reply #7 on:** April 22, 2007, 01:34:56 pm »

I tested the fan by jumping it directly to the battery and it worked. I think there was an incomplete ground connection. I still don't know why the fan doesn't come on while the car is running. The coolant starts overflowing and still the fan doesn't switch on, despite a new thermoswitch!

:x

jtanguay · « **Reply #8 on:** April 22, 2007, 01:56:55 pm »

well i can almost guarantee that the relay for the fan is super corroded into its connector. if you can work it out of the harness with some wd-40 or lube, make sure to clean the contacts... that might fix it.

if jumping the thermoswitch wires does nothing, a new thermoswitch won't fix your problem...

you really shouldn't let your coolant overflow... drive with the heater on if you must, but do not let the coolant overflow!!!! just asking for HG problems there.

oh btw, if you manage to get the relay cleaned up, get some dielectric grease and slop it on! she won't give ya any trouble for another few years after that...

rallydiesel · « **Reply #9 on:** April 22, 2007, 04:52:26 pm »

OK, the problem has been solved. I found the disconnected ground wire. The fan finally came on at quite high temps. The coolant was steaming out of the overflow bottle pretty good by the time the fan came on. I will get the lower temp thermoswitch next time I order stuff because this one waits too long before it kicks in.

I found out the relay has nothing to do with the fan if the A/C is broke. The relay makes the fan go to the higher speed if the A/C pressure gets too high. Since I have no gas in the A/C, the relay has no purpose on my car. I am sick of reading wiring diagrams now. :?

jtanguay · « **Reply #10 on:** April 22, 2007, 09:05:28 pm »

actually the relay near the fan has everything to do with cooling your car without a/c... (unless you were talking about the a/c relay...)

the a/c relay under the dash controls the fan's low speed (via the resistor wire). only if the resistor is blown will the fan not come on, and this is usually why the a/c system fails... BUT there are a few safeguards that help keep the system in check... sort of! there is a low pressure cut off for the compressor.. meaning that if the pressure is too low, the compressor will shut off... the pressure will get too low if it overheats and bursts a seal! there is also a high temp switch next to the low pressure cut off, which will actually turn up the speed of the fan to cool the hot refrigerant better, and reduce the risk of blowing your compressor from overheating. if your wiring or fan fails at this point, the system will be basically trying to kick on high speed for the fan in order to save itself... eventually it overheats, kicks a seal and the refrigerant blows out, low pressure kicks in and the a/c system cannot be turned on. this pretty much saves whatever life is left in the compressor.

when the car requires cooling, it receives the additional speed bypassing the resistor until it reaches its desired temp. once that temp is reached, the circuit opens and then the a/c resistor takes over again.

still my advice to you is to pull the a/c relay under the dash and just forget it.

i would also recommend you replace the overflow cap... it shouldn't be spewing any coolant unless it's super hot.

even the hottest thermoswitch will still keep the engine cool enough so that it doesn't spew its coolant.

you might need to flush your whole coolant system too... that usually seems to do wonders! I flushed mine... but i did it incorrectly as i did it without the t-stat installed :oops:

what i do is run the car with the cap off and a digi temp monitor in the bottle... i was able to determine that the t-stat opened at 86.5C (most likely hotter inside the motor) and the coolant temp dropped to around 85-84C, then started to level out at around 86C... a minute or so later it reached 90C... i didn't let it get too hot because of the fact that it was steaming off quite a bit of water....