MazdaRx7Power

my car doesnt overheat unless i punch it. someone told me that if the waterpump housing is all rotted and corroaded inside that its probably that. so what do you guys think? i have all new radiator hoses, water pump, and clutch fan with an addition 17" cooling fan mounted on the radiator. but it still starts to overheat. i dont mean like all the way up but the needle goes about 3/4 of the way up. but i still dont want it running that hot. so can anyone help me out.

MazdaRx7Power

i also have the 2 sleeve alternator pulley that has two belts so it makes more contact with the water pump and their tightened. no cats so they can't be clogged.

1FastT2

iTrader: (1)

Have you flushed the entire coolant system lately? It probally isn't the prolbem but it certainly wouldn't hurt.

MazdaRx7Power

yup i flushed it about a week ago. new cap and new stat.

1FastT2

iTrader: (1)

You may just want to take the water pump housing off and see what it looks like, that way you could eliminate that or fix the prolbem.

SureShot

On my 200,000 mile 87 the aluminum casting behind the pump was eroded by the turbulence of the high revving pump. The bypass valve seat under the thermostat had about a 4mm chamfer eroded away, and there was a 6mm hole eroded through the wall between the inlet and outlet side. I finally spotted the problem when the back side of the housing sprung a leak. I fabricated repairs with Bondo Marine Epoxy Putty Stick. The stuff is great.

Ryde _Or_Die

Ya i thought this may have been my problem as well for a while. Then one day the car started to run really cool again. All by itself without doing anything to fix it. It ran perfect for about a month then started to overheat again. Then the battery went dead. Now my car is a lawn ornament. I wanted to take the water pump off to see if thats what is was but I wouldn't even know what the housing looks like good. By running hot it makes the alternator not work as efficiently, right?