fannitti

So I flushed my heater core the best I could. There is prob still **** in there but whatever I'll replace it, it's better then the no heat I have had forever. I switched from colored to open cooling system on my 89 renix. I added a new model year tstat housing on it with the temp sensor fitting for the electric fans. After I flushed heater core my temp gauge was reading better then it ever has. Before the flush it would go to read and I'd have no heat but the jeep never over heated! When I played with the flushed of the heater core and tryed running it and adjusting fan controller I got better readings from gauge. You think it's worth just replacing heater core and seeing what happened. Will a clogged heater core cause flow issues for temp readings? I've tryed multiple sensors in the back of the head and even a diff gauge all together thinking the cluster could be wrong. Any help would be great thanks guys.

cruiser54

Heater core should't cause bad readings.

fannitti

Really I donno what I got going on then.

SteveMongr

Perhaps a tool is needed to assist with diagnoses. Infra-red temperature gun can pinpoint temperatures in the cooling system.

fannitti

I'm gonna do heater core anyways as I don't think everything got out and go from there. How hard is it on a renix to do? After I replace it I'll use our BG coolant flush machine at work and pull a vaccum and suck all the coolant out and fill it with new stuff hopeful that helps next step is head gasket I see that leaking on the outside of the block but don't see anything in the coolant or engine oil

toasterknight

Stop throwing parts at in and actually do some diagnosis. The heater core is a huge job the requires taking the whole dash out. Have you verified if your gauge is actually correct?

fannitti

Yea two diff sensors and a auto meter one.

toasterknight

Have you burped the system to remove air? The heater core has little effect on the temperature of the coolant.

Oswalla

Air bubble is what I was thinking too .

Did you take hoses off core and flush it in reverse with a garden hose ? Seems to work for me that way over the years on various rigs I've owned.

When you did the closed to open conversion did you leave the heat control valve or eliminate it ? Might have a bad heater valve not opening if its still there. Easy enough to open or close by hand to see.

Radi

+1

You can't fix the problem until you determine whether it's a gauge issue, or an actual temperature issue. Well you can, but it's the hard and expensive way.

fannitti

No heater valve. I wasn't sure if heater core being clogged controlled the flow in the system. I got the hose from the tstat to the bottom of heater core and top of header core to water pump.

fannitti

Ok so a little update. I didn't some more dish. I used a heat gun and all the hoses are reading as they should. At the tstat house by the sensor it's reading 195 cuz that's what I have in there and that is where the sensor for the fans are. I'll check in the am on a cold start and see what temp at the tstat housing where the sensor is that the fans come on cuz the fans stay running and never cycle off.my head gasket is leaking down the engine block but it's not leaking into the oil nor do I see oil in the coolant.im gonna hold off on the heater core for now. Any ideas cuz I'm running of of them. Why do my fans stay running and what dose the gauge always read red and fluctuate. Cuz somthing by blocked in the coolant passages?