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Water pump advice

@denata
The one Twisted Steel Performance (Chris) shows at the bottom of the list is the correct one.
88894035 - 251-603 - ACDELCO 6.5 water pump-screw on fan, stamped impel.
(19168609, 12456231)
Send him a pm for how to order it and be done without worries.

@n8in8or Can you describe how you made your restriction fitting for the water pump please. I remember your method seemd much easier than how I did them.

Denata- All your hummer is missing for the complete balanced flow system is that restriction fitting. Provided you use the AC Delco spin on pump like it had originally.
But I seriously suggest adding a high quality after market engine temperature gauge and install the probe in the passenger head to the rear easily accessed once the engine cover is off. The factory hummer gauges used for temperature from 1996 and newer were total crap for accuracy.
I found the post in my thread.

 
Again I'm late finding this out..lol...I upgraded to the screw on fan and pump from the 4bolt when the truck had overheating issues .. and I have dual thermostats.. I believe I got 170 degree or 175 degree stats... someone on here told me the part numbers and brand but damned if I remember what they are.. just bought what I was told... But I THINK I got the pump from AutoZone...I honestly don't remember now... Don't remember anyone telling me about putting the other thing in the pump... In hindsight I should have changed the timing chain while I had it apart or switched it to the gears.... Way too much work to pull it back apart just to find out... She don't run hot anymore that's what I cared about at the time..
 
Got a pump today..
Ordered "ACDelco 251-603"
The number 2555711 is cast on the pump.exactly the same as on the Hummer.
View attachment 70188View attachment 70189View attachment 70190
Check that pump over good, I just noticed the sticker on the box showing AC Delco and the year 1995! all the newer delco labeling has a qr code that identifies it not to be counterfeit. if it just has simply sat on a shelf somewhere for that long I would be weary of the internal seals and such. if you look on the ac delco site they show the new labeling types.
 
Check that pump over good, I just noticed the sticker on the box showing AC Delco and the year 1995! all the newer delco labeling has a qr code that identifies it not to be counterfeit. if it just has simply sat on a shelf somewhere for that long I would be weary of the internal seals and such. if you look on the ac delco site they show the new labeling types.

The year is the copyright date for the AC Delco name:

ACDelco[edit]
1995 saw a re-branding of AC-Delco. The hyphen was dropped and ACDelco received a new logo and marketing initiative. The "AC" bullseye and semicircular Delco logo disappeared from product packaging
 
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