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  #1  
Old 18-04-08
900T89 900T89 is offline
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Default over heating again

my car is over heating and im not sure why. The pass side fan (a/c fan) is broken and wont even spin by hand. I dont use the a/c at all, I even disconcerted it. During over temp situations does the a/c fan assist the main fan?
I ordered a new fan today to replace the broken one.

I changed my thermostat today and bleed the system with hopes that this would cure the problem. Clearly did not !!!

It might be the watter pump but I am leaning toward NO.

Any ideas. The blower does not really blow any hot air, not loosing any coolant.

Maybe I should just flush it out???

HELP need to fix ASAP
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  #2  
Old 18-04-08
philbert philbert is offline
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Is the other fan working when it gets up to temperature?

Is it boiling over or just reading hot on the gauge?
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  #3  
Old 18-04-08
900T89 900T89 is offline
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Quote:
Originally Posted by philbert
Is the other fan working when it gets up to temperature?

Is it boiling over or just reading hot on the gauge?
yes the other fan is working it gets up too temp and it turns on for a few seconds and then off for a few and then on again.

Today when i came back from a short drive the fan was on constantly and then did as stated above.

Its not boiling over as far as I can tell just reads very hot on the guage. like just below the red mark, which is way too hot.

This is really bugging me. I know there is a valve in the upper rad hose. could that be possibly not working right?
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Old 18-04-08
philbert philbert is offline
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That's not a valve in the upper radiator hose, that's a sensor that will cut off the a/c when the temp gets too high.

If the fan comes on when the temp gets almost to the red, the temperature sensor in the radiator (upper driver's side of the radiator) is probably shot. The relay (driver's side fenderwell) may be on its way out also if it cycles on and off every few seconds. Me personally, I'd bypass the relay (unplug relay, run a jumper between the yellow and yellow-striped connectors) and replace the radiator temperature sender. If you need one quickly, just go to your local auto parts store and get one...Saab 900/9000 and many VWs all use the same one. They're *maybe* $10.00.

AND I'd replace the bad radiator fan...soon.
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  #5  
Old 18-04-08
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Grizzly Grizzly is offline
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Default

Hi 900T89,

You wrote: The pass side fan (a/c fan) is broken and wont even spin by hand.

Not sure if it matters, but with my Saab, the main fan is on the right hand side (passenger side), and the a/c fan is on the left (drivers side). Perhaps you ment to say it the other way round, or perhaps your main fan is not working. That would explain why your a/c fan only kicks on once you are almost in the red zone, because it is supposed to activate itself, when the temp gets dangerously high.
Its possible that your main fan is indeed broken, or that the temp sensor needs replacing. The fact that you are not leaking coolant is good, and hopefully its just the temp sensor gone bad.
Griz
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  #6  
Old 18-04-08
900T89 900T89 is offline
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Quote:
Originally Posted by philbert
That's not a valve in the upper radiator hose, that's a sensor that will cut off the a/c when the temp gets too high.

If the fan comes on when the temp gets almost to the red, the temperature sensor in the radiator (upper driver's side of the radiator) is probably shot. The relay (driver's side fenderwell) may be on its way out also if it cycles on and off every few seconds. Me personally, I'd bypass the relay (unplug relay, run a jumper between the yellow and yellow-striped connectors) and replace the radiator temperature sender. If you need one quickly, just go to your local auto parts store and get one...Saab 900/9000 and many VWs all use the same one. They're *maybe* $10.00.

AND I'd replace the bad radiator fan...soon.
I have ordered a used fan from a junk yard and will have it in a day or two. Do you think its ok to just leave the relay jumed or is it tied into a bunch of other ****? it does cycle on and off every few sec. weither its really hot or just at normal temp.

tomorrow I am replacing the water pump to see if that makes a difference.

When I did the t-stat I had to remove a wire to that seemed to be the temp sensor. (single wire) You said there is also a temp sensor on the right side of the rad. that controls the on/off switch for the fan. Are there 2 separate sensors or are they related?

I just removed the a/c completely pump a few mins ago for access to the water pump and I would never use the ting anyway. Correct me if im wrong (the fan on the right is the main, the fan on the left is for the a/c) while sitting in the drivers seat.

Quote:
Originally Posted by Grizzly
Hi 900T89,

You wrote: The pass side fan (a/c fan) is broken and wont even spin by hand.

Not sure if it matters, but with my Saab, the main fan is on the right hand side (passenger side), and the a/c fan is on the left (drivers side). Perhaps you ment to say it the other way round, or perhaps your main fan is not working. That would explain why your a/c fan only kicks on once you are almost in the red zone, because it is supposed to activate itself, when the temp gets dangerously high.
Its possible that your main fan is indeed broken, or that the temp sensor needs replacing. The fact that you are not leaking coolant is good, and hopefully its just the temp sensor gone bad.
Griz
thanks grizzly
hahah im getting confused with the fans and what side they are on. i have a left side drive car. maybe the main fans are on the same side as the drivers seat...? I would like to think thats not the case though. I will replace the temp sensor tomorrow as well as the water pump and we will see what happens.

thanks guys for all the help. this car is totally alien to me being its a turbo and an automatic. I have never owned either in my life. but a good learning experience.
I really like the saabs and think im addicted
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  #7  
Old 23-04-08
900T89 900T89 is offline
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ok its been about a week now and I cant seem to get my car to cool down.
It is overheating and yesterday it boiled over.

what I have done ;
replaced the thermostat
discovered the water pump is nearly brand new
flushed the entire cooling system, rad. and engine and heater core.
I have bled the system and now get nothing but coolent coming out.
replaced the broken a/c fan with a good one now and it was working on the way home today .

removed the a/c pump

I was driving home today with all the mods done as stated above with both fans running and it still was over heating.
my next thought it to replace the fan switch on the rad. (upper right side)
please help this is my daily driver for about 3 hours a day. all help is apprecaited.
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  #8  
Old 23-04-08
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jglavin jglavin is offline
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Are you sure the rad is not clogged?
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  #9  
Old 23-04-08
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Default

Quote:
Originally Posted by 900T89
ok its been about a week now and I cant seem to get my car to cool down.
It is overheating and yesterday it boiled over.
Did it need a lot more coolant after overheating? Maybe the system wasn't completely bled and was short a couple of litres -- easy to do, ask me how I know.

EDIT -- just noticed you haven't replaced the fan thermoswitch yet. As philbert said a few days ago:
Quote:
If the fan comes on when the temp gets almost to the red, the temperature sensor in the radiator (upper driver's side of the radiator) is probably shot.
That was good advice!
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Old 23-04-08
900T89 900T89 is offline
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is it possible im not bleeding it right ???? I just let it warm up and crack the bleeder???


i am replacing the switch tonight. I have been waiting for it like 5 days now and am ready to see if that works. thanks
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  #11  
Old 23-04-08
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Grizzly Grizzly is offline
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900T89,

You can never be to sure when priming the system. Here are the instructions that I borrowed from Townsend.

Originally Posted by Tom Townsend
make sure the temperature control for the cabin heat is set to hot.

Then locate the brass bleeder nipple on top of the thermostat housing. Hold the bottom part of the bleeder with an 11 mm or 7/16" wrench and open the top portion of it with another same size tool. This allows air to exit the system as you add the coolant. leave the bleeder open until a steady stream of coolant comes out and the reservoir is filled to the MAX line.

Close the bleeder temporarily and start the engine. You will probably notice that the level in the reservoir has fallen a bit and will see a few air bubbles coming up in it. Open the bleeder screw again and let it stay open until it flows a steady stream of coolant again. Shut it tight this time.

Drive the car until the fans come on and then park it and once more open the bleeder screw until no air is expelled. Top up the level in the reservoir to the max line and let the car cool off.


Griz
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  #12  
Old 23-04-08
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Hu Flung Dung Hu Flung Dung is offline
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Default

Quote:
Originally Posted by 900T89
ok its been about a week now and I cant seem to get my car to cool down.
It is overheating and yesterday it boiled over.

what I have done ;
replaced the thermostat
discovered the water pump is nearly brand new
flushed the entire cooling system, rad. and engine and heater core.
I have bled the system and now get nothing but coolent coming out.
replaced the broken a/c fan with a good one now and it was working on the way home today .

removed the a/c pump

I was driving home today with all the mods done as stated above with both fans running and it still was over heating.
my next thought it to replace the fan switch on the rad. (upper right side)
please help this is my daily driver for about 3 hours a day. all help is apprecaited.
OK not to cause any more confusion, but I don't recall BOTH fans running on my Saabs unless the A/C is turned on. It's passenger side = coolant/antifreeze cooling fan, radiator hose above it houses thermo switch that shuts the A/C off if the engine overheats. Driver side fan = A/C fan that came on ONLY when I would turn the A/C on. Right above it, in the radiator itself, is the thermo switch that tells the radiator fan (not the A/C fan) to turn on because the antifreeze/coolant is too hot. I remember going through this back when my '86 had overheating problems, but in my case it was just the coolant/antifreeze fan was dead so I replaced it.
Also there's a relay that leaves the coolant fan running after you turn off the car, if the fan had been running already...the relay is timed to stick shut for a certain time period then open and the fan will shut off. Sometimes that relay dies and makes the fan stay on, people walk away into the house after coming home from a drive, and the fan runs until the battery dies. At least that's what happened to me on one occasion.
Double and triple check the water pump, belt, fans, thermostat (take it out if you have to and drive it like that for a day, I did a couple times).
I know it's a pain but hang in there and hopefully you'll figure it out!
Good luck - HFD

one more thing - that thermo fan switch in the radiator on the driver's side (not the A/C one located in the hose on the passenger's side) was HIDDEN under the air intake duct on my 8V NA. I couldn't see it or the wire going to it unless I pulled that intake duct away! On the 16V I can see it plain as day, nothing in the way. It's also an NA engine. I think basically if you don't run your A/C, forget that thermo switch in the passenger's side radiator hose altogether for this troubleshooting! I don't know what else it's used for except to turn OFF the A/C if the engine overheats!
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  #13  
Old 24-04-08
900T89 900T89 is offline
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ok i think we are working here. I replaced the switch and have not had it over heat yet. Will find out for sure today on the ride home though. hu flung
I did notice last night when i came home that the fan stayed on for a few extra sec. after I shut the car down. (never happened to me b4) must have been b/c of the new stitch.
I am currently running the a/c on even though I dont have any pump just for the sake of the fan for added cooling.
thanks guys, will report more this afternoon.
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  #14  
Old 24-04-08
900T89 900T89 is offline
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sucksess

drove home today for 2 hours and had no over heating issues. it got warm when i got on the highway and then it came down and ran at a normal temp. I guess the switch did it.

thanks again for all your help saab cental rules !!!!!!!
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