Sheared water pump

Hi, installed a magnuson sc to 1 gr fe good for a month then it sheared the water pump off….. mechanic put new one on and tested same thing happened????
Any tips n tricks before I start crying!

simon

 

It sheared the pump off?
I’d expect a belt failure first, very strange?

@Torspd you ever seen/heard anything like this? BTW it’s a Hilux if you didn’t notice.

 

I've never heard of that happening, only thing I can think of is the belt being to tight maybe?
Got any pictures of it?

 

somehow routed the belt in a way that it shouldnt?

Side note: The way that the belt drives the pump/pulley is kinda odd

 

Is the tensioner seized?

 

My mate said maybe too much tension on the belt but one would think the installer and a1 mechanic would be on to this…..no belt breakage on both times

 

Forgive me for second guessing you.
Definitely sheared, more like “ripped off”. Impressive, but sucks.

Hopefully you get that figured out.

 

I've never seen anything like that before, I've seen shafts shear off when the bearing goes out but not the whole pump broke off.
I wonder if the fan was maybe out of balance (obviously it is now) and that led to the failure?

 

Tensioner not seized

 

Wow. That’s something.

My guess, something the belt rides on is seized. Or incorrectly routed belt. But one would think immediately after starting the belt would break or jump off or at least make a horrible screeching noise first. I’d give every pulley a spin, including the supercharger pulley. Confirm the belt that comes with the supercharger is correct, assuming it doesn’t use the original belt.

 

Usually if over tightened you'd hear the alternator howling long before damage like that.

I'd be looking at the install for alignment.

The belt arrangement on the 1gr is a bitch with superchargers.

 

I can’t imagine a belt overpowering a cast housing of water pump. Something else is afoot there. What brand water pump and did you follow the proper torque specifications?

 

Obviously the only solution is to trade my stock manifold for your current wheely one that's too heavy.

 

Impressive to say the least.

I've never seen a water pump ripped apart like that.

 

Wow. Never seen anything like it.
Question. Did you modify the S/C pulley? Did you reduce it from its original design?
If that's not the case, I would chuck the viscous fan and convert to electric fan. I think that boat anchor fan that attached to the WP is the root of your shear WP.
You can try a new viscous fan, the old one probably too much play in the bearing.

 

I'm thinking maybe a little (ok, a lot) too much tension on the belt.

 

can probably play the banjo on that belt.

 

This has my vote. Long ago my girlfriend had a late 70s Toyota that had a bad fan clutch, and it was tearing apart water pumps in a few hundred miles. Leaking, not the catastrophic failure described here. After I replaced it, problem solved.

OP’s may be setting up a really strong vibration at a certain RPM and causing this failure mechanism. You’d think anything that bad would be felt in the cab, tho.

 

There are no signs of damage to the belt and all pulleys spin freely? If so, as a former racing engine builder and student working his way through college in an aluminum die casting plant, here an improbable, but possible scenario.
The water pump was probably die cast. As the molten 1400°F aluminum flows into the mold under pressure, water flows through the mold and cools the aluminum to a solid state. If the aluminum is cooled too quickly, too slowly or unevenly, the part can be significantly weaker. An experienced inspector would probably be able to tell. Critical things can be checked by pressure testing, not water pumps.

 

What are the odds that two in a row are due to this?