Water Pump Question

[luc]

how many miles on the pump?

You said that the car "overheat" when you step on it.
What's the temperature?
Assuming that when you step on it,you are not doing that in neutral at a stop,that's pretty well remove the fan clutch from the equation.(when you move you have air flow)

Pump.most of the time when a pump go bad it is the bearing/seal that is the problem.
Pumps usually have what is called a "weeping hole" basicaly a 1/16 hole where you will see some coolant leak coming out from it if the seals/bearing are bad.

180 thermostat do nothing to change the temperature of the engine.
That's only mean that it is fully open at 180 and that the engine cannot run cooler than 180.
On a rare case the pump impeller can get loose, int his case there is no water circulation in the engine.
Since the viper don't have a regular radiator cap, the way to check it would be to start the car cold and with your hand on the upper radiator hose see if sudenly, when the thermostat open the hose become hot.
If it does you can assume that the problem is not with the pump.
That leave you with a stuck thermostat, incorect timing(don't know if is possible with the computer)or a cloged radiator.
Good luck.
Luc,

 

[JonB]

You already have my vote: WATER PUMP IMPELLER

I consulted w/ Ben "Dyno ****" Treynor numerous times, while he was meticulously diagnosing EXACTLY your condition, when EXACTLY your mods were in place (mostly from PartsRack, Tnx.) I was therefore concerned, and the WATER PUMP proved the culprit.

 

[Doug Supercharged Vipers]

FastFreddie -

Have you tried pressure testing the <u>cap</u> and cooling system yet?

...And later on down the line (when you rectify your overheat problem) upgrade the cooling fan.

Keep us posted,
Doug

 

[treynor]

FF,
Your symptoms sound exactly like mine. Car would be fine as long as I was just putting around. As soon as I got the revs up, it would go into massive overheat mode -- coolant puking, red temp light, heater would stop working -- the whole works. Sometimes if I kept driving [normally] the temp would suddenly plummet, sometimes it would stay hot and I'd have to pull over. Ted May @ Valaya diagnosed the problem as a bad water pump, and showed me where the impeller had cracked along the pump shaft. It would spin with the shaft as long as there wasn't much force being exerted, but once we passed the static friction boundry (i.e., when I revved) it would start to freewheel and I'd lose coolant circulation.
Ted replaced the water pump, and it's been dandy ever since. I'd strongly suggest looking there as well.

 

[99 R/T 10]

Hey FF,
This may sound like a stupid question, but did the overheating problem start just after you replaced the thermostat?

Mike

 

[99 R/T 10]

Hey FF,
This may sound like a stupid question, but did the overheating problem start just after you replaced the thermostat?

Mike