Low Temp Guage/No heat

On my Mazda:

I flushed and filled the cooling system. I ran the car for a LONG time with the cap loose, then tightened the cap and ran it some more. I took it for a drive yesterday, and, figuring the temp was rising and the fan was kicking on while idling, everything was OK.

When the car is in motion, the temp guage barely moves above Cold. If I let it sit and idle, it builds up heat, but drops again as soon as the car starts moving.

I got a new thermostat, and installed it using the old thermostat, the instructions on the box and my Haynes for instructions. Refilled, let the car get good and HOT, sealed the system and went for a drive. Barely above Cold again!

I used Peak anti-freeze, a new gasket, Hi Temp gasket compound, etc, etc.

I believe the system is bled out...ran the car until warm, ran it up to about 2500 RiPpeMs for about 5 minutes, idle again till the fan cam on,

2500 RPMs again, then sealed the system and ran it until the fan came on.

Other than sticking a piece of plastic or cardboard in front of the radiator, any other ideas?

BTW, the last time I ran the car, I left it idling for 5 minutes after a

10 minute drive, and anti-freeze was dripping out of the overflow bottle...
Reply to
Hachiroku
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So both the new and old thermostat are doing the same thing? I'm not quite sure which one you used by your saying: "> I got a new thermostat, and installed it using the old thermostat"

Somethings to check: direction of the thermostate, position of the jiggle valve that lets air out. You probably have a big air pocket that pushes the coolant out after 10 minutes of running.

In general, too much cooling can point to a stucked-open thermostat, but overflowing can point to a stucked-closed thermostat.

Hachiroku =E3=83=8F=E3=83=81=E3=83=AD=E3=82=AF wrote:

Reply to
johngdole

Should have said "...using the old thermostat as a guide" I also did what Haynes told me to...

Wouldn't that cause overheating? And, the way I did it should have bled the system out.

As far as the 'jiggle valve', the old one didn't HAVE one! Usually the 'jv' goes to the top, so that's where I put it.

Yeah! I don't get it!

Reply to
Hachiroku

What is the opening temperature on the replacement thermostat? In most cars, the thermostat spring should be oriented down.

I forget whether your car has a transverse-mounted engine, but if it does, check to make sure the electric cooling fan is not stuck on. If it has a longitudinally mounted engine, make sure the fan clutch is disengaging. Coolant mix should be 50-50 - straight coolant causes problems like freezing and overheating.

Reply to
Ray O

Wow...the one I took out didn't have a 'jiggle valve' in it (lunched through the cooling system?) but the holes where it would go were at the top. I put the new one in the same way.

I also replaced the cap today. I know on some Caravans/Voyagers, if the cap is shot the same thing happens. No go...

I had a two-hour wait for tires today ($29 each...woo hoo!) and I let the car run for about 40 minutes. I think perhaps the mistake I was making was opening the radiator cap to top it off. I started using the overflow bottle and it seems to be getting better, but, I noticed a big puddle of coolant under the car, that wasn't seeming to come from the overflow bottle. I believe a new (reman'd) water pump might be in order, too.

I chickened out! I'm having the belt and the pump replaced Friday by a local garage, and the struts done all the way around by another. AutoZone has a tool loaner program, but I didn't like the looks of the spring compressor they were loaning out...

Reply to
Hachiroku

Hachi - When you let it idle until it 'warms up', what does the temperature gauge read? And when you drive it and it cools off, does the gauge go all the way back to cold?

Reply to
mack

A bad radiator cap usually causes overheating, not lack of heat.

Yup, after you get the radiator mostly full, top off from the overflow bottle and let the radiator suck it in.

Look for the source of the puddle under the car. You could go from lack of heat to meltdown pretty quickly.

I would tackle the t belt and water pump if there is a reasonably warm place to work on the car.

I don't do struts because doing them without a wall-mounted professional strut compressor is very dangerous, and you need to get an alignment afterwards anyway.

Reply to
Ray O

I have a heated garage. Get your ass out here! ;)

Reply to
Hachiroku

Goes up to halfway, the fan kicks on, and as long as it idles, it acts OK. When you drive the car it goes down almost all the way to cold.

Reply to
Hachiroku

That's tempting!

Reply to
Ray O

You know where I live (basically!)

It'a actually been kind of nice here lately. Saturday was about 48, and Sunday was *almost* 60. Today got over 48. Pretty good weather for being outside at this time of year!

Reply to
Hachiroku

We had single digit temps over the weekend, but close to 50 degrees today around here. Of course, nothing ever needs fixin' when the weather is nice!

Reply to
Ray O

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