Aux. Turbo pump checking

[russ.s.southerlin@den.mmc.com]

Guys,
After Dave Head's commenst about the turbo pump I rigged up a light 
(just used a old tail light bulb) to the elec. connector of the pump so 
that when the pump would be running the light will come on. It looks 
like the pump runs whenever the fan runs after shutdown, it also runs 
for a couple seconds when the engine is started. Therefore I think all 
the other electricals are ok even though the light probably doesn't have 
the same elec. load as the pump.

One question I have is how do you know that the pump is working (i.e. 
bad relay or switch) since you can't tell if it is actually pumping.

My old pump would run when connected to 12V but the impeller was frozen 
up. The impeller is magnetic coupled to the motor so that the motor can 
be running but the impeller is sitting stll. I think the only way to 
check for sure would be to disconnect the coolant hose and look down 
into the plastic housing while connected to 12V and see if the impeller 
is turning.