Contour Enthusiasts Group Archives Forums General Troubleshooting Water pump- white impeller?

I have noticed that my car runs a little warmer at idle since having the water pump replaced. It is, however, in the normal range and turning on the fans via the AC makes it run on the cool side.

Good news is I guess this means I have the metal impellor. I guess it's fine as long as it doesn't run too hot. It was okay the other day in nasty stop-and-go traffic and approx. 80 degrees, so it should be fine. I may find and check any and all bleeders, though...

Cason Grover
Houston
Silver E0

I got one at AutoZone at Hillcroft and Bellaire, and the impeller was black plastic. I was in a hurry (wanted to have a spare in the trunk before setting off on a long road trip), so I didn't open the box before leaving the store... :rolleyes: I'll check the part number later.

The earlier water pumps are the ones that failed. SO??? have any 1999 owners have one fail? "Cuz the later ones are 'sposed to be ok... so I hear.
And I wonder about a metal impeller and hydro-corrosion: (where little bubbles form from the high speed of the blade, and eat up the metal...) My paranoia gland set on "High Alert"

The 'corrosion' you speak of is called cavitation burn. I experienced it on my Yamaha 200 outboards as I had gotten a couple of small nicks on my props, which caused bubbles to form, and now my props look like they rusted, which is not possible since they are high-grade stainless.

I just pulled apart my old waterpump that I had replaced in my 99 SVT, which was built before 12/98, and it had the tan impeller. Hope my new OEM pump lasts as good as the 1st one!

Elizabeth,

If cavitation occurs, plastic won't hold up any better than metal. The bubbles that form can generate 1000's of psi impact pressure when the burst upon contact of the impeller surface. I seriously doubt that this situation generates bubbles of that magnitude (pressure and flowrate dependent.)

I would think/assume that the manufacturers would use a meterial like aluminum, or a stainless alloy to prevent corrosion cracking (but only an issue if you decide to run salt water in the coolant system.) BTW, I replaced the water pump in my Honda Magna and it used a metal impeller. 6+ years sitting in coolant solution with no deterioration to the impeller blades. The mechanical seal failed causing it to leak out of the weep hole (only driven 600 miles/year before I picked it up,)

Just my blind $0.02

Later,
David

I just replaced the WP on my '99 with the Autozone model. It apears that the impeller is a cast aluminum piece with machinined vane faces. My '99 had a rather good looking white ABS plastic unit. I almost wish I did not do it since the stock one looks plenty beefy to me...

I replaced the WP on my E0 SVT over the holiday weekend using the GMB AutoZone pump.

Looks like I caught it just in time too at just over 30K. The stock unit w/ black impeller had just started to scrape against the back of the pump housing and a hairline crack was starting to form on the impeller.

My car has always run cool usually between the letters N and O and never over the half way mark during extended idling in hot summer traffic.

With the new pump, new Ford thermostat and new Ford temp gauge sender, the needle on the gauge sits just below N and sometimes just barely in the normal range scale.

Obviously the new metal pump does work, but are the lower temps caused by the pump? Can anybody concur these findings on their cars? Yes, I am using the same 50/50 concentration as before using Ford premium coolant along with a bottle of Red Line Water Wetter. BTW, I was already running Water Wetter before the pump change.

IIRC, the stock black had only 6 blades on the impeller and the GMB unit has 7 or 8.

Thanks
Steve

I replaced mine at around 38k and opted for the metal impellar WP from Autozone. I wish now I had gotten the plastic impellar cause I don't think that the metal one pushes enough water through at idle. Mine ran just about the left to the middle of the O and now it runs about a letter warmer and if i'm sitting in traffic....it will go to the A unless I turn on my A/C which I HATE to do because the RPMs hang when i let off the gas for about 3 seconds. Someone mentioned about air being in the system.....how do you check for that? When i replaced my pump...i replaced the thermostat as well. Old one looked good but figured since i had it apart already....may as well go ahead and replace it. SVTcop@aol.com Email me if anyone has any suggestions. Thanks.

The one from Autozone should have a metal impeller. It can be installed without removing anything else in the car if you have a short handle ratchet, and you're willing to do it from underneath.

As for the temperature changing by a few letters, it could be the temperature sender. Had mine replaced under warranty around 38k miles. The guage had changed from reading around 'o' to reading around 'm'.

Go with the metal impeller GMB unit. I own a '95 with the black plastic impeller that lasted over 50K . My car does run cooler now, but that is because I noticed the black plastic was wearing away over time. I only had a noticeable increase in water temperature at failure, when the plastic impeller fractured in half seperating from the drive spindle.