TantricScorpio

Ok, now I've taken out my thermaostat, I just spent $70 to get the radiator flushed and cleaned and add a new gasket, for some reason when it idles it's fine, but when I start to drive it, it starts burning up. What's the deal. Should I go get the whole system flushed and try to eliminate all the air in the system? What should I do next? -Steve

TantricScorpio

I just went outside and after 5 minutes of idling it overheated, what's the freakin deal!!! This thing is starting to really **** me off.

Roy James

Not too sure, it could be lots of things. There is a "wheep hole" on the top of the WP that is usually a good indicator of when the WP goes bad. You should bleed the system anyways, air is bad. And if you took your thermostat out that could be your problem completely, the water flows too fast through the radiator before it has a chance to cool down and just heats everything up. Check the clutch on your fan (saying you have shaft fan on still). Does your car smoke any? Good Luck

DomFD3S

Water pumps as with most mechanical items do wear out after a while. You're talking about a 10+ year old car. Things are going to go out after some time.

When was the last time the water pump was changed (if you have this information)?

Also, what do you mean by "it starts burning up"?

Lastly, you may have some REALLY BIG air bubbles caught in the cooling system if it is not properly flushed out.

TantricScorpio

so would it be wise to get the whole system flushed, I don't know when the pump was replaced, the motor is rebuilt so I hope they didn't give me a bad pump.

TantricScorpio

when i say it's burning up i mean it overheats

Crionics

Just as kind of a basic test, start the car up and get it at least warm if not poerating temp. Turn on your heat. if it doesn't get warm, your pump isn't circulating water or a bad heater core. If it does work, take off the fan and check the weep hole. There will just be hints of coolant.

But before you do any of this, flush and bleed your coolant system. It's very easy and quick, and you are prolly due for a change anyway, especially if your collant is anything but green, like brown. And check how much anti-freeze to put in. If you are in a warm climate, you don't need to put as much in.

TantricScorpio

For starters my heat doesn't work, what is a weep hole and where is it, why would i check this weep hole?

SureShot

Just because the fan is spinning, doesn't mean it's working good enough.
The fan clutch will start to wear out after 100000 miles.
When your car is warmed up, the fan speed accelerates directly with the engine speed, up to 4k.
The fan clutch slips to maintain ~4k as the engine revs higher.
If yours is starting to slip at 2500, you will overheat.

Also check that you have the right thermostat.
Besides the stat's main valve disc, there is another (spring loaded) disc that closes a bypass port inside the pump housing.
If the bypass port is open, you will overheat.

TantricScorpio

check it, I have a 16 inch electric fan that I put in, I totally eliminated the stock fan and clutch. How do I know that I have the right 'stat?

SureShot

If the fan is running like it was before the overheating, then it's OK.

Replace the stat - it's cheap.

Crionics

like I said earlier, it could also be your heater core that is clogged or a bad thermostat. I would change my thermostat with a MAZDA replacement (dont buyt one from pep boys or autozone because it wont last) and flush my system first.

But, if your heat doesn't work, then it may not be a bad idea to check the weep hole. In order to look at that, you will need to get a mirror on a stick (you can pick up a cheep one by the cash registers at autozone-I made on with an old compact case) and grab a flash light. If you cant get one of these, then you will need to take off your fan and shroud, which is pretty easy too, assuming the nuts aren't too stuck.

The weep hole is on the bottom of the water pump. It is easy to see, since it is the only hole down there, but it is on the part that juts out from the main pump body, kind of in that bend. basically., what happens, is after l a long period of use, the tension of the belts on the water pump pulley causes the bearing to give out and the shaft begins to "bend" down. This is how every water pump that I have had to change failed.

SureShot

The Mazda stat has a small bleed hole through the mounting plate, with a loosly fitting rivet in it.
(And of course the spring loaded disc sticking down below.)

christi

Did you buy a mazda thermostat? If not, take the one you have in now, and go buy a mazda one. It's only about $15.

TantricScorpio

the one that I bought was from Checker, when I compared the two they look completely different. I noticed that little dangling thing through the bleed hole. the 'stat from checker doesn't have that. Fact is that the whole system was overheating before when I had the old motor in, now with the new motor it's still overheating. So it may be the 'stat. I also am going to take it down to get it flushed out today. -Steve

TantricScorpio

Crionics, if I see green in the weep hole the pump is good?

christi

IMO, I'd just do a entire coolant flush, switch it to a mazda thermostat (recommanded by alot of folks on here. Aftermarket thermostats don't do justice with our cars.), get a new WP (doesn't have to be mazda, I don't think. I didn't use a mazda one, and mine hasn't overheated since..besides a bad main cat).. and try it that way.. if it is still overheating.. Well I'm not too sure after that point.

TantricScorpio

I'll give it a whirl. Thanks Christie.

Crionics

A green weep hole = bad pump. ou don't wanna see anything that would indicate water leakage.

OC_

funny thing when i changed my water pump...

Its a pretty big job the first time you do it since the whole assembly the water pump is on has to come out.

but check out this pic...

you can fit a 6'4" man inside the engine bay, with the engine still in there. this is my bro..

you can close the hood too....

easy p-cheesy

christi

hahah! I knew that was coming.. nice job, easy.

GatorRX

Don't mess with non-Mazda water pumps. If you compare the two side-by-side (cheapo and Mazda) you can easily see the difference in the quality and the design of the impeller...

Electric fan is running, I assume? Check that its wired right! If it is wired backwards, it will move a lot of air, but in the wrong direction, and you might not notice it. If you have it hard-wired, without a thermostat, this would cause a problem at speed and maybe at idle, depending how you have it mounted.

And throw a Mazda thermostat at it, no harm done there if it doesn't fix the problem. Make sure you really soak the nuts holding the t-stat housing with penetrating oil for a few hours before you work on it, though, they have a habit of corroding and snapping (ask me how I know).....

Your heater core wouldn't be an issue because its a separate circuit for the cooling...