OK, we've all been seeing waterpump thread failures recently, however, no on has really answered what is the technical reason that waterpumps fail?
That is of course always a consideration, but I have to believe that GM provided the mechanical design and the design paramaters. And I would be surprised if the manufacturer built things that are likely to fail like the seal. The seals and many (most?) of the parts making up the pump come from second and third tier suppliers.Or it could just be GM sourced their pumps from the lowest competitive bidder?
While I am sympathetic with your statement, I have no evidence other than the current failure rates that its a good design or a bad design. The water pump loading is not a particularly challenging environment, nor are the loads all that high. I guess I would like to understand better what is the basis for your statement.I have to say it's poor design....the undue stress that is put on a direct drive pulley. Has anyone looked at the '02 Vette (I think). They had a direct drive alternator and A/C compressor. Wondering if their failures are as numerous.
BINGO!!! digalingaling!! and the winner is Da Ghost...:thumbs: Whatcha want fer ur prize buddy..:willy:I have to say it's poor design....the undue stress that is put on a direct drive pulley. Has anyone looked at the '02 Vette (I think). They had a direct drive alternator and A/C compressor. Wondering if their failures are as numerous.
Good points.In response to GS' comment re: "lowest bidder" - it is incredibly rare that a domestic car maker does anything BUT grant the work to the lowest bidder. It's been a while since I've supplied anything direct to an OEM but a few years back it was common for them to select the lowest price, require annual price reductions, AND have the supplier commit to covering warranty costs. In many cases the supplier will also design the component or system.
The theory is that the supplier knows his business so he's going to design something that is cost effective to build and if he's responsible for the warranty cost, he's not going to produce something that is prone to failure. The problems start when the supplier has to reduce his price every year for 3 to 5 years. That requires greater efficiencies in his process and/or reduced material costs. Remember the Ford/Firestone tire failures? Nobody will admit it, but Firestone left out a wind of wire in order to get their costs down.
I think the thread is headed in the right direction though. There must be an environmental or mechanical reason the Kappa goes through water pumps more than other vehicles. I'd be shocked if the seals and many of the components are not common across many different water pumps and vehicles - possibly even non-GM vehicles.
Shock loads, heat, etc as many of you have brought up would be suspicious. It would be interesting to see a breakdown of GXP versus N/A, auto versus manual, etc.