I recently had to replace the radiator return hose.

I lost about a gallon of coolant because of the leaking hose and after I replaced it and refilled the system, I checked under the radiator cap to make sure the coolant was flowing normally. I seem to remember the coolant flowing pretty quickly from right to left (looking at it from the front), but now I don't see any flow going on at all.

I managed to get some air out and another half gallon of coolant in there, but I'm still not seeing that normal flow. The heater vents do blow hot air but I'm worried there's still air in the system and it might cause me some problems on my 1,200 mile trip I have planned this weekend.

The temperature gauge doesn't work. It never has worked and I don't know why. I already checked the wiring at the back of the gauge and it looks fine. If the damn thing would work I wouldn't be so paranoid about the possibility of having air in the system. The spedo has been working sporadically ever since I got the van as well. I recently had to replace the Engine Control Module because the battery wasn't getting charged but it's charging now and that may have been the reason my spedo wasn't working (it was dropping in-tune with my blinker on a low battery). I haven't had a chance to drive it around yet because my plates are expired from having it sit around while trying to find the ECM. This is probably not related to the temp gauge though.


So,

Should the coolant be flowing from right to left when looking under the radiator cap? Is there a burp valve somewhere to purge the air from the system? Does anybody have any suggestions from their experience on this subject?

Thanks,

Kevin

 

You won't see any coolant moving inside the top tank of the radiator until the thermostat opens, and the thermo won't open until the engine reaches operating temperature. If the radiator is full you can go ahead and start the engine again and leave the radiator cap off.

Make sure the heater control is set to hot and turn the fan selector to low speed. As the engine warms up you should see the coolant level begin to go down from the top tank and you can add more 50/50 mix if you need to bring the level back up -- this is when you should see flow in the top tank.

 

I just go for a drive around the block and that usually gets the air out.

 

The way air is removed from the coolant is through a few heating and cooling cycles which burps the air into the coolant overflow bottle. When the water heats up it expands and the air gets trapped in the top of the radiator, then a properly operating radiator cap opens and the air is expelled into the the bottle. When the engine cools and the water shrinks only coolant is sucked back into the radiator. These heating and cooling cycles will burp all air from a system providing the system is sealed, the radiator cap is operating properly, and the coolant overflow bottle system has no leaks.

 

It's not burping itself like it should so I'm going to replace the radiator cap. I'm also going to replace the thermostat sending unit. Will let you guys know how it goes.

 

Agreed, start with a new radiator cap. Also check or replace the overflow hose. I recommend using small hose clamps. If that hose isn't air tight the coolant won't siphon back into the radiator.

 

I replaced the radiator cap and the sending unit.
Using a multimeter I tested the two wires that plug in to the sending unit. One is with about 4.5volts the other is grounded.

I'm still not getting any reading on the temp gauge.
All it does is go from slightly above cold, to rock-bottom cold.

I finally renewed my license and plates and I got a chance to drive it around. Now It's not shifting into 4th gear. Any suggestions?

 

I will try putting zip ties on the overflow hose as well. Thanks for the tip.

My spedometer used to work intermittently, now it's not working at all. I checked the connection behind the instrument cluster and I can't see any obvious problems. All of the lights come on, just the gauges aren't working.

Upon closer inspection I can see that parts of the copper strips on the green circuit board are slightly dulled, like maybe the board got hot at some point.

Since I couldn't find any other reason for the temp gauge to fail and my spedo has completely failed as well, and they're both on the same circuit board.. I think the problem might be the board itself. Then again maybe it's a grounding issue. How do I track down a faulty ground wire on the cheap? I have a multimeter somewhere around here but no money for a shop or expensive diagnostic tools.

I talked to my dad's friend Alex up in Idaho and he suggested that my missing 4th gear might just be due to stuck valves. I think he might be right because the thing has just been sitting there for 3 months and it worked before I parked it. My uncle here in Colorado Springs also said it might be stuck valves and I didn't even mention what Alex said to me earlier.

I need to make a 1200 mile trip from here in CO Springs to northern Idaho here in the next few days to deal with a family emergency. Failure is not an option here, I have to make this trip happen.

So any help from you guys would be greatly appreciated.

Thanks,

Kevin Hyatt

 

I drove it around the block a couple times this morning and noticed my odometer isn't working either. But my turn signal indicators which are on the same panel are working.

Tranny still won't shift to 4th. Coming from a complete stop in 1st gear if I'm heavy on the gas pedal, it seems like it's shifting in to the passing gear or something because the engine will rev higher than normal for a moment.

 

You might have loose pins on the circular connector on the back of the cluster assembly. It is fairly simple to fix -- take a look at the following thread for my solution to this annoying problem:

https://dodgeforum.com/forum/dodge-r...ghts-help.html