Heat gauge is alway's hott

[speedfreek500]

Hello my heat gauge is alway's hot and have very little heat.put a new head on and i replaced the rad.I have cycled the cooling system about 5-6 time's and still run's almost pegged over.Also replaced the coolnt temp sensor also.I know i need to flush the heater core,cause i had oil going into my coolant system.

[speedfreek500]

Sorry for got to mention the fan come's on also.I seam to have the problem when driving normal down the highway.

[Clay]

if your heater core is plugged, then that is the reason you have very little heat in the car.

now when you say the heat gauge is always hot, do you mean its in the red all the time? When the fan comes on, does it stay on for very long periods of time? Is your coolant staying clean? or did you change it 5 or 6 times because it kept turning into mud?

[turbovanman²]

What he said. If the fan is cycling on and off, then its not overheating and the guage/sending unit is bunk.

Go here for advice on cleaning out the heater core-

http://www.turbo-mopar.com/forums/sh...ad.php?t=20785

[speedfreek500]

well how come going down the highway at 50mph it still pegg's over to hott?I know the heater core is plugged not worried about that now just want to solve the running hot problem now.

[turbovanman²]

well how come going down the highway at 50mph it still pegg's over to hott?I know the heater core is plugged not worried about that now just want to solve the running hot problem now.

Are you sure its overheating and not a guage issue. Have you pulled over quickly and verified the overheat condition?

[IROCNOROLL]

Hello my heat gauge is alway's hot and have very little heat.put a new head on and i replaced the rad.I have cycled the cooling system about 5-6 time's and still run's almost pegged over.Also replaced the coolnt temp sensor also.I know i need to flush the heater core,cause i had oil going into my coolant system.

This could also be a sign of a headgasket, cracked head scenario. The cyl. pressure loads and locks the heater core circuit with air and prevents circulation.

[Turbodave]

Does it only do it on the highway?

Are your running a stock cooling fan? Is it wired correctly? If you're not sure take a piece of paper and hold it in front of the rad when the fan is on, it should get sucked to the rad.


Just suggesting this because I had experience where the hacked wiring on my neon had the fan polarity wrong. On the highway at 50mph the car would start to overheat. If I slowed down or sped up it was fine. Turns out the fan was fighting the airflow when the car was moving causing very little movement past the radiator.

[denviola]

This could also be a sign of a headgasket, cracked head scenario. The cyl. pressure loads and locks the heater core circuit with air and prevents circulation.

Check the oil for signs of water (looking at the dipstick), although it is probably ok. If the temp gauge rises rapidly, goes very high quickly and then goes back almost to normal with up and down ticks, you have a head gasket or head issue. Pressurize the coolant system, that pump tool is cheap or you can rent it inexpensively.

Denny

[mwrenn]

A easy way to check your temp gauge is to pull the wire off the send unit on the block, it's the single wire on the right front of the engine, not the two wire plug on the t-stat housing. Anyway, ground the wire and turn your ignition on, the temp needle should peg full hot if the gauge is good. If it doesn't peg, you've got a bad gauge.
Your t-stat might be sticking, or you could have an air bubble trapped in the housing. If the t-stat is working the radiator fliud should be really hot if the gauge is showing hot. Just touch the top tank to check temp. (Don't get burned) LOL. To bleed the t-stat housing, pull out the top allen plug in the housing and make sure coolant (a little) comes out there.
A good way to check your water pump is to see if it's able to circulate fluid through the heater core, a weak or defective pump won't be able to push fluid through the heater hoses to the core. Hope this helps.

[4 l-bodies]

how come going down the highway at 50mph it still pegg's over to hott?I know the heater core is plugged not worried about that now just want to solve the running hot problem now.

I think you should diagnose the overheating problem before you start throwing parts at it. Before you replace the radiator consider this. If you know your heater core is plugged, then how is the coolant supposed to circulate? The waterpump needs to pump the coolant somewhere, otherwise it doesn't work. In other words, you are driving the vehicle around without any bypass. Your water pump would be just cavitating until the thermostat opens. This alone can cause overheating. Try bypassing the heater core (it doesn't work anyway). Run the line beneath the thermostat water box (hard-line) back to the bypass located either at waterpump inlet or radiator (depending on what type of car you are driving). See if there is any difference.
Also make sure you have the correct waterpump and or pulley on the vehicle. In 89' they started using a waterpump at spun backwards. I've seen both of these this done before, which caused overheating (or running very warm) in both cases. Also make sure you have a thermostat installed in the car. Without the restriction, the motor can circulate coolant so fast it doesn't have enough time in the radiator to remove any heat. Seen that before too.
Todd