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CMac89
11-09-2009, 03:55 PM
In the past 2-3 weeks, I have had two different hoses blow on me. The first was the heater return hose, that connects from the hard line to the ECT-to-Intake manifold junction and the second was the thermostat bypass hose. After I replaced the heater hose, all was well, no problems. The thermostat bypass hose blew on my way home and I'm not sure how much coolant was lost (I'm thinkin about half.)

After I replaced the thermostat bypass hose, I have an overheating problem now. Before this hose blew, the gauge would hover right around N-O. Now it heat cycles from M to a little past it.

The fan is coming on and I have cracked the bleeder several times. One thing that I did notice is that there isn't any pressure in the upper radiator hose. There aren't any leaks anywhere and the heater works. I was thinking head gaskets, but the heater doesn't smell like exhaust in the least and I'm not losing any coolant.

This is a '94 SC, by the way.

thirdbird
11-09-2009, 04:09 PM
One thing that I did notice is that there isn't any pressure in the upper radiator hose. There aren't any leaks anywhere and the heater works. I.

T stat snafu or backwards?

paul

fastsc92
11-09-2009, 06:01 PM
T stat snafu or backwards?

paul

He's a rebel....he doesn't run one at all

CMac89
11-09-2009, 06:56 PM
I have a thermostat in my '94 (the car that I am talkin about on this thread), but not the blue one. I actually daily drive this car, so I need a thermostat in it.

My gauge could be wacky, so let me ask this. What temperatures do the fans come on and shut off on a stock '94 car? The puller fan is coming on and shutting off, so that leads me to believe that the car may not be as hot as the gauge says. If someone knows that information, then I can rule it out.

My '89 says the stock fan goes to high speed at 228*, which is still too hot.

XR7 Dave
11-09-2009, 07:11 PM
but the heater doesn't smell like exhaust in the least and I'm not losing any coolant.

This is a '94 SC, by the way.

Why would your heater ever smell like exhaust? :confused:

CMac89
11-09-2009, 07:26 PM
The blue car did whenever the head gaskets were leaking. I can only guess that combusted gases enter the coolant system. All I know is that problem went away after I put new HGs on it, at the time.

decipha
11-09-2009, 08:07 PM
i never cracked open the gen2 bin file but the gen1 supercoupes ecu is set to turn the fan on at 220 and shut it off at 216 for the low speed, high speed comes on at 228.

fturner
11-09-2009, 08:13 PM
i never cracked open the gen2 bin file but the gen1 supercoupes ecu is set to turn the fan on at 220 and shut it off at 216 for the low speed, high speed comes on at 228.

That means we have 4 generations of the ECU ;).... and they all have the same settings as you said.

Fraser

decipha
11-09-2009, 08:20 PM
lol true i was just summarizing the sc's as i do

89-93 gen1
94-95 gen2

CMac89
11-09-2009, 10:11 PM
Well, I suppose I'll just change the thermostat and see what happens.

fturner
11-09-2009, 10:21 PM
Since you have a QH and the software, swap it over and see what is really going on in there... JJJJEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE EEZZZZZZZZZZZZZZZZZZZZZZZZZ!!!!!

Get er done! :D:p;)

Fraser

90turbo1
11-09-2009, 10:23 PM
get cap pressure tested.

also there might be air trapped in the system some where, it just needs to be worked out or its trapped some where other than were the bleed screw is.

i know this is not a bmw but they do that similar thing when they have air trapped inthem some where.

CMac89
11-10-2009, 02:29 AM
Since you have a QH and the software, swap it over and see what is really going on in there... JJJJEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE EEZZZZZZZZZZZZZZZZZZZZZZZZZ!!!!!

Get er done! :D:p;)

Fraser

I don't haaveee theeee CZAW0 fiiiiilllleeeeeessssssss!!!!!!! :)

http://www.modularfords.com/forums/images/smilies/blowup.gifhttp://www.modularfords.com/forums/images/smilies/blowup.gifhttp://www.modularfords.com/forums/images/smilies/blowup.gifhttp://www.modularfords.com/forums/images/smilies/blowup.gif

MrSnow
11-10-2009, 02:41 AM
Mines been doing about the same thing.... But it was a loose connection on bottom of the rad then the one next to the throttle body.... :mad: Super been pissing me off I should change the thermostat but it seems like Advanced Auto doesn't know what one is on this car.... Working on the Power Steering tomorrow anyway. :mad:

Mike8675309
11-10-2009, 09:21 AM
Are you sure you got all the air out of the system? Next is a bad thermostat. If the thermostat was exposed due to low coolant levels it's possible that it corroded slightly and now is limited in how much it can open.
I've gone through 3 thermostats in the last 8 months, and I've noticed that the design of the stock replacements are not ideal.

CMac89
11-10-2009, 11:17 AM
Are you sure you got all the air out of the system? Next is a bad thermostat. If the thermostat was exposed due to low coolant levels it's possible that it corroded slightly and now is limited in how much it can open.
I've gone through 3 thermostats in the last 8 months, and I've noticed that the design of the stock replacements are not ideal.

I have cracked the bleeder with the thermostat open and I have done it with the thermostat closed. I'm not exactly sure I have all of the air out.

I drove the car last night (about ten degrees cooler out) and it the hottest it would get is the R. If you're at a low speed, or an idle, it will go a little past the M. The water temperature is responding to outside temperature. I have checked several times and there still is very little pressure in the coolant system. I have one of the caps with the pressure relief valve on top of it and very little air is being bled off.

David Neibert
11-12-2009, 12:00 PM
I have cracked the bleeder with the thermostat open and I have done it with the thermostat closed. I'm not exactly sure I have all of the air out.

I drove the car last night (about ten degrees cooler out) and it the hottest it would get is the R. If you're at a low speed, or an idle, it will go a little past the M. The water temperature is responding to outside temperature. I have checked several times and there still is very little pressure in the coolant system. I have one of the caps with the pressure relief valve on top of it and very little air is being bled off.

Casey,

Easy way to check the cap is squeeze the upper radiator hose while watching the coolany recovery tank. If coolant or air bubbles circulate in the recovery tank when squeezing the hose, then the cap isn't sealing. I had to put a second rubber gasket on mine to get it to seal.

David

CMac89
11-12-2009, 06:03 PM
Casey,

Easy way to check the cap is squeeze the upper radiator hose while watching the coolany recovery tank. If coolant or air bubbles circulate in the recovery tank when squeezing the hose, then the cap isn't sealing. I had to put a second rubber gasket on mine to get it to seal.

David

I tried this, once I got home, and there aren't any bubbles appearing or being heard after I squeeze the upper radiator hose.

I also noticed that there was pressure in the upper radiator hose, so I'm leaning towards a bad thermostat. Temperatures are higher than I like, but they don't trail off towards the no fly zone.