'94 Shadow heater hoses? Anemic heater!
JH32552
12-18-2006, 08:37 PM
If someone has a Shadow or Spirit w/ a 2.5 engine.......
Would you please check to see if the upper or lower hose coming out of the heater core goes to the water pump?????
I'm running out of options trying to get heat in this car. I was just wondering if someone accidently got the hoses to the heater core mixed up and that is the reason that it's not throwing much heat.:banghead:
I have changed the t'stat twice:banghead: .
" installed a new coolant temperature sensor:banghead:
" " " " temperature sending switch:banghead:
got new radiator cap:banghead:
radiator fan relay:banghead:
flushed and backflushed entire system (incl. heater core):banghead:
bled and burped the system :banghead:
Today, a guy at the dealership pressure tested the system and there are NO leaks, and it held pressure fine.
What else is there? Anyone know? :banghead:
Jackie :banghead:
Would you please check to see if the upper or lower hose coming out of the heater core goes to the water pump?????
I'm running out of options trying to get heat in this car. I was just wondering if someone accidently got the hoses to the heater core mixed up and that is the reason that it's not throwing much heat.:banghead:
I have changed the t'stat twice:banghead: .
" installed a new coolant temperature sensor:banghead:
" " " " temperature sending switch:banghead:
got new radiator cap:banghead:
radiator fan relay:banghead:
flushed and backflushed entire system (incl. heater core):banghead:
bled and burped the system :banghead:
Today, a guy at the dealership pressure tested the system and there are NO leaks, and it held pressure fine.
What else is there? Anyone know? :banghead:
Jackie :banghead:
KimMG
12-18-2006, 09:39 PM
Clogged or restricted heater core? Is the temperature of the heater hoses about the same? If so equipped, is the heater valve fully opening?
KManiac
12-19-2006, 12:17 AM
Jackie:
Here is a quick run down of the cooling system and heater core hose routing, at least this is the way it is in my 1991 2.5L.
Basic cooling system - The water pump sucks cold water out of the radiator from the lower radiator hose. The cold water is pushed into the engine block, where it picks up heat from the engine. Hot water is pushed through the thermostat, through the upper radiator hose, to the radiator.
Heater Core - Hot water from the engine block flows through a tap in the head just below and behind the thermostat. This hot water flows through a 5/8-inch diameter hose to the upper hose connection in the heater core, at the firewall. After passing through the heater core, cold water passes out the lower hose connection, into a 5/8-inch diameter hose, which wraps around the front of the engine and attached to an approximately 3/4-inch hose tap on the suction side of the water pump, at the same point that lower radiator hose attaches.
The quirky thing about this heater core return hose that runs between the heater core and the connection at the water pump is that it is a specially made hose with a 5/8-inch end at the heater core and a 3/4-inch end at the water pump. The original return hose in my Shadow had a Chrysler part number stamped on it. I had to replace mine with a special order hose from Chrysler at a cost of $61.00. Hopefully, someone did not try to replace this hose previously and then rigged something different because they were either too cheap to buy the correct, special hose or too confused to figure out what they were dealing with.
Make sure the hoses are routed as I described and let us know if they are different.
Here is a quick run down of the cooling system and heater core hose routing, at least this is the way it is in my 1991 2.5L.
Basic cooling system - The water pump sucks cold water out of the radiator from the lower radiator hose. The cold water is pushed into the engine block, where it picks up heat from the engine. Hot water is pushed through the thermostat, through the upper radiator hose, to the radiator.
Heater Core - Hot water from the engine block flows through a tap in the head just below and behind the thermostat. This hot water flows through a 5/8-inch diameter hose to the upper hose connection in the heater core, at the firewall. After passing through the heater core, cold water passes out the lower hose connection, into a 5/8-inch diameter hose, which wraps around the front of the engine and attached to an approximately 3/4-inch hose tap on the suction side of the water pump, at the same point that lower radiator hose attaches.
The quirky thing about this heater core return hose that runs between the heater core and the connection at the water pump is that it is a specially made hose with a 5/8-inch end at the heater core and a 3/4-inch end at the water pump. The original return hose in my Shadow had a Chrysler part number stamped on it. I had to replace mine with a special order hose from Chrysler at a cost of $61.00. Hopefully, someone did not try to replace this hose previously and then rigged something different because they were either too cheap to buy the correct, special hose or too confused to figure out what they were dealing with.
Make sure the hoses are routed as I described and let us know if they are different.
JH32552
12-19-2006, 08:30 PM
Kim..... I have flushed and back flushed EVERYTHING on this darn car. I have "warm" but don't have "heat" coming from my heater. I don't think the car has one of those valves. If it does, I have no clue where it is... do you?
KManiac,
I understand that your car has the water coming OUT the bottom hose on your heater core. I just checked my '94, and the upper hose goes OUT to the water pump area... the opposite of yours. Do you think this would make a difference?
Plain and simple.. the car is running much colder than it should. I think I am going to get a real water temperature gauge (with numbers) and install it to see what the car is really running at.
The car is getting TERRIBLE gas mileage too. I'm sure the computer is getting a signal that the car is running too cold and it's feeding way too much gas.. hence the rough idle. I filled the car yeaterday. Drove it about 90 miles, and only have 1/2 a tank left!!!!!!
Jackie
KManiac,
I understand that your car has the water coming OUT the bottom hose on your heater core. I just checked my '94, and the upper hose goes OUT to the water pump area... the opposite of yours. Do you think this would make a difference?
Plain and simple.. the car is running much colder than it should. I think I am going to get a real water temperature gauge (with numbers) and install it to see what the car is really running at.
The car is getting TERRIBLE gas mileage too. I'm sure the computer is getting a signal that the car is running too cold and it's feeding way too much gas.. hence the rough idle. I filled the car yeaterday. Drove it about 90 miles, and only have 1/2 a tank left!!!!!!
Jackie
KManiac
12-19-2006, 09:50 PM
Hey Jackie:
By now you are probably going bald dealing with the cooling system. Hang in there.
The temperature slide control on the dashboard controls the opening and closing of the heater control valve. This valve regulates the flow of heated water into the heater core. Open the valve (slide to hot), you get heat. Close the valve (slide to cold), no heat. When the hoses are routed correctly, water passes through the valve first before it enters the heater core.
I suspect that your heater control valve is not opening and may be disconnected from the slide control on the dashboard. With the hoses turned around, hot water can slowly enter the heater core, giving the luke warm effect, without the water actually flowing through the core.
Here is what I suggest to test the integrity of the valve. Disconnect the hoses from the heater core connections on the firewall. Next, install lengths of 5/8-inch bulk heater hose on each connection. With the temperature selector on the dashboard in the full hot position, stick a garden hose in one hose, turn on the water and see if water comes out the other hose. If not, the valve is stuck shut.
I know that the valve is under the dashboard somewhere, but I have never tried to either find or replace one in the Shadow. Try the test I described above and let us know what you find.
By now you are probably going bald dealing with the cooling system. Hang in there.
The temperature slide control on the dashboard controls the opening and closing of the heater control valve. This valve regulates the flow of heated water into the heater core. Open the valve (slide to hot), you get heat. Close the valve (slide to cold), no heat. When the hoses are routed correctly, water passes through the valve first before it enters the heater core.
I suspect that your heater control valve is not opening and may be disconnected from the slide control on the dashboard. With the hoses turned around, hot water can slowly enter the heater core, giving the luke warm effect, without the water actually flowing through the core.
Here is what I suggest to test the integrity of the valve. Disconnect the hoses from the heater core connections on the firewall. Next, install lengths of 5/8-inch bulk heater hose on each connection. With the temperature selector on the dashboard in the full hot position, stick a garden hose in one hose, turn on the water and see if water comes out the other hose. If not, the valve is stuck shut.
I know that the valve is under the dashboard somewhere, but I have never tried to either find or replace one in the Shadow. Try the test I described above and let us know what you find.
JH32552
12-19-2006, 10:23 PM
Here is what I suggest to test the integrity of the valve. Disconnect the hoses from the heater core connections on the firewall. Next, install lengths of 5/8-inch bulk heater hose on each connection. With the temperature selector on the dashboard in the full hot position, stick a garden hose in one hose, turn on the water and see if water comes out the other hose. If not, the valve is stuck shut.
When I thought I was backflushing the heater core (I was only flushing because the hoses are backwards) I was shooting water into the top hose connection and the water was coming out just fine. Wouldn't that be a good test as to the integrity of the valve?
I am genuinely afraid of playing with the heater core's inlet and outlet pipes too much, fearing leaks. I actually cut the top hose off when I flushed the heater core since the hose was long enough to waste a couple of inches.
Did I mention that the car sat idling in a friends driveway the other day, and the radiator fan never came on once? I was actually able to hold on to the upper radiator hose for quite a long time before it became too uncomfortable. It just seems to be running much too cool. The gauge will start going up at times, but then drops in the space of a few seconds.
I'm beginning to think this little bugger is POSSESSED! :disappoin
Jackie
When I thought I was backflushing the heater core (I was only flushing because the hoses are backwards) I was shooting water into the top hose connection and the water was coming out just fine. Wouldn't that be a good test as to the integrity of the valve?
I am genuinely afraid of playing with the heater core's inlet and outlet pipes too much, fearing leaks. I actually cut the top hose off when I flushed the heater core since the hose was long enough to waste a couple of inches.
Did I mention that the car sat idling in a friends driveway the other day, and the radiator fan never came on once? I was actually able to hold on to the upper radiator hose for quite a long time before it became too uncomfortable. It just seems to be running much too cool. The gauge will start going up at times, but then drops in the space of a few seconds.
I'm beginning to think this little bugger is POSSESSED! :disappoin
Jackie
KManiac
12-20-2006, 12:12 AM
Gosh, Jackie, this has me baffled, as well. ...and I don't have that much hair to start with!
What you continue to describe sounds like there is either no thermostat installed or the thermostat is stuck open, causing continuous circulation of water through the radiator and not allowing the water to warm up. But given the fact you have replaced the thermostat more than once makes this scenario unrealistic. The only way I can see you installing the thermostat incorrectly is by putting it in backwards, because it will fit in the outlet housing pointed in either direction. But the stampings in the thermostat tell exactly which direction to point it. And even if you did install it backwards, it should still cause enough of a restriction to flow to allow the coolant to heat up or even overheat. Did you verify that 195F was stamped on the thermostat? Anyway, I am out of ideas. Its hard to move forward with this without looking at it with my own eyes. Maybe then I might see something that I cannot visualize in my head. Let me know if you have any questions.
What you continue to describe sounds like there is either no thermostat installed or the thermostat is stuck open, causing continuous circulation of water through the radiator and not allowing the water to warm up. But given the fact you have replaced the thermostat more than once makes this scenario unrealistic. The only way I can see you installing the thermostat incorrectly is by putting it in backwards, because it will fit in the outlet housing pointed in either direction. But the stampings in the thermostat tell exactly which direction to point it. And even if you did install it backwards, it should still cause enough of a restriction to flow to allow the coolant to heat up or even overheat. Did you verify that 195F was stamped on the thermostat? Anyway, I am out of ideas. Its hard to move forward with this without looking at it with my own eyes. Maybe then I might see something that I cannot visualize in my head. Let me know if you have any questions.
JH32552
12-20-2006, 09:11 AM
KManiac,
Obviously you feel my frustration with this problem. I, and everyone that looks at this car, are baffled as well. I read an article last night that states a problem such as this is the result of air in the system. I will try bleeding the air out via the bleeder on the t'stat housing again today. Oh, and by the way.... the t'stat is most definately installed correctly.
When and IF I ever find the problem, I will certainly post it for you. Thanks for all your efforts my friend!
Jackie
Obviously you feel my frustration with this problem. I, and everyone that looks at this car, are baffled as well. I read an article last night that states a problem such as this is the result of air in the system. I will try bleeding the air out via the bleeder on the t'stat housing again today. Oh, and by the way.... the t'stat is most definately installed correctly.
When and IF I ever find the problem, I will certainly post it for you. Thanks for all your efforts my friend!
Jackie
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