Water pump pulley walking off

[83ChevyK5Blazer]

In 30 miles Ive lost 2 water pump pulleys due to the pressed on flange walking off the shaft.

First pump has been on the truck 3k plus miles, driving down the interstate i lost the belt and accessories, swapped the pump, and it did the same thing 30 miles later...

Engine is stock 454, kwik preformance serpentine adapters, with 1994 tbi serpentine brackets and serpentine accessories.

I'm at a loss.

 

[83ChevyK5Blazer]

Could it be the harmonic balancer?

 

[83ChevyK5Blazer]

It looked fine, no rubber moving

 

[Wes Harden]

I thought the 1st was a fluke, I'm sure I have seen it b4 but I can't remember when. I can't think of any reason the belt would due this. all the pulleys line up? You've no fan on there to pull it off.
My only advise at this moment is to zap that hub with a mig welder. a spot or 2 on the front should do the trick.

edit wrap the pump snout in wet towel to keep the seal cool, when you zap it.

 

[83ChevyK5Blazer]

We made it to a hotel after playing the run it to 210, cool it off let it run to 210 game for a couple hours to get 1.5 miles

 

[Wes Harden]

sucks man, rest well and get your old pump welded and swap it. After seeing you 2nd failure went looking, it seem to happening more across many makes and models. The consensus is weld it

 

[Wes Harden]

if you didn't have to fight to get the new the belt on, or loosen the alt or something like that, then that 1/8" shorter is not causing this.
A scenario has accrued to me since earlier posts.
What if the impeller was dragging inside the pump. Serpentine belts have good grip on the pulley, impeller stops for a second, and pulley doesn't slip= hub turns on shaft. Then spins off a few miles later. IDK if I'm grasping here or not.
When you get to your destination, I would like to see the insides of these pumps.

 

[83ChevyK5Blazer]

I'll def take apart the original to see if there is a failure. I'm hoping some daylight will help in figuring it out

 

[nvrenuf]

Same brand on each pump?

Such a bizarre failure, could something be pushing the belt forward? Is there a lip on your pulley for the belt to push against?

 

[fourwheelerjeff]

any answers???
get it figured out??
on the road?

 

[83ChevyK5Blazer]

First was a napa, second was acdelco. Just leaving willomet motor and fab with a welded pump.

 

[83ChevyK5Blazer]

@AgDieseler threw 4 welds around the flange, and fitted the pulley a bit better.

Huge shout out and thank you to @AgDieseler for the help and hospitality!

 

[nvrenuf]

That’s awesome! CK5 brotherhood for the win!

 

[AgDieseler]

@AgDieseler threw 4 welds around the flange, and fitted the pulley a bit better.

Huge shout out and thank you to @AgDieseler for the help and hospitality!

Only too happy to help. Good meeting y’all.

David

 

[83ChevyK5Blazer]

I think its the crank pulley causing the problem, we are going to try again.

 

[83ChevyK5Blazer]

Broke the water pump in half, 144 miles from Shreveport

 

[sweetk30]

something WAY out in another place to be causing all this trouble . . .

15+ years in a shop and since then i have never seen a pressed on pulley come off .

 

[nvrenuf]

Good lord man!

 

[Wes Harden]

Is this factory GM tbi serpentine set up, or is it aftermarket?
Sometimes is easy to miss route the belt, esp if the sticker is missing.
I have to ask is the belt turning the pump in the correct direction ?

 

[83ChevyK5Blazer]

It's factory 94 tbi brackets, with kwik performance adapters for the big block