The newly redesigned BMW 330i does away with the belt driven water pump. New electric water pump standard. Something to think about for those doing conversions.

I know a few V8 guys are running e-waterpumps so it's not too new, but others have been too shy to use them.....

The nice thing about these pumps is you can do away with the thermostat and just control the speed of the pump, based directly on water temp. The pump will always spin fast enough to provide adequate flow (no problems with idling after a high-load run causing overheating because the pump is spinning too slowly), and never so fast it cavitates.

It will be interesting to see how long these pumps live. The early Davies-Craig electric water pumps had relatively short lifespans (20K miles or thereabouts).

Gm plans to go to electric pumps. These will be run at 42volts DC. I was just reading about some of the new things we will see from GM.

QUOTE (BIGKAT_83 @ Aug 4 2005, 12:08 PM)

Gm plans to go to electric pumps. These will be run at 42volts DC. I was just reading about some of the new things we will see from GM.

car manufactures have been talking of higher voltage use for years......we'll see when it really happens

QUOTE (lapuwali @ Aug 4 2005, 11:58 AM)

The nice thing about these pumps is you can do away with the thermostat and just control the speed of the pump, based directly on water temp. The pump will always spin fast enough to provide adequate flow (no problems with idling after a high-load run causing overheating because the pump is spinning too slowly), and never so fast it cavitates. It will be interesting to see how long these pumps live. The early Davies-Craig electric water pumps had relatively short lifespans (20K miles or thereabouts).

What I normally observe with mine is that after sustained high-speed driving, then getting off the off-ramp into stop & go traffic, the engine temperature actually goes down a few degrees. Dedenbear's product engineer gave me a life expectancy of several thousand hours, I forgot what the specific number was. I remember estimating it to exceed typical lifespan of a stock Chevy waterpump. I asked him what failed on these pumps based on warranty repairs. He said that all had failed due to foreign material wrapped around the impeller causing it to stall. That material was either teflon thread tape or radiator leak stop. I have an electric water pump on my solar water system and it's still running after 20+ years, usually 6-8 hours a day. For sure it's a different application, but that's good reliability for a hostile environment (160-180F water at high pressure).

I can't wait until they get rid of the belt-driven alternator in favor of an electricly driven one