water pump number 2 in one year. what am i doing wrong?

1986.5supra_kid

Veteran Member
Joined
Dec 7, 2012
Location
south Carolina
TDI
2010 jetta
this is the second water pump to fail at the seal for shaft. i noticed the pulley has just a hair of runout so im guessing i need a pulley too just to count that out this time. first pump was the original. this one was a bosch unit with metal impeller.
 

GTiTDi

TDIClub Enthusiast, Macht Schnell! Vendor , w/Busi
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Oct 18, 2010
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3 Spruce st Wareham, gateway to Cape Cod Massachus
TDI
'91 GTI CJAA swap,'02 Jetta wagon ALH swap, '03 GTI 1.8T rally car, '03 Sprinter 3500
I would blame the pump rather than anything you are doing incorrectly. Bosch has been putting their name on all kinds of stuff lately...I only use original VW, Geba or Graf pumps.
 

Abacus

That helpful B4 guy
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Nov 10, 2007
Location
Relocated from Maine to Dewey, AZ
TDI
Only the B4V left
How tight was the belt? I've seen people tear them out in no time because they had the belt cranked down tight 'so it wouldn't slip'. I leave mine just slightly loose and tighten as needed. Never had an issue. That it failed at the seal indicates to me it's a belt issue.
 

Ol'Rattler

Top Post Dawg
Joined
Jul 3, 2007
Location
PNA
TDI
2006 BRM Jetta
I would agree. on MK3's, it is very easy to get the water pump P/S belt tensioned to tight. The tensioner requires a very light touch.
 

kooyajerms

grocery getter
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May 5, 2004
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Pomona, Southern California
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97 B4V (mine), 11 x5 35d (hers) 04 V10 (that one you want), 2014 Q7 (mom's) 74 Shasta 1400
Bit misleading to say you had two fail in the same year when that first one has 200k on it. Leave that one out of the equation. I say it's overly tightened and or the Bosch unit. Get Graf/hepu/oem.
 

Ol'Rattler

Top Post Dawg
Joined
Jul 3, 2007
Location
PNA
TDI
2006 BRM Jetta
IDK about misleading so much. His 2nd pump failed prematurely. He never actually said that the 1rst W/P failure was premature.
 

MarsBar

Veteran Member
Joined
Apr 28, 2008
Location
San Jose, CA
TDI
B4V#2 "Flash", 2000 Jetta GL, B4V#1 "PaTuDI" (2008-2018 RIP)
I've always heard that the water pump gets changed every other TB job.
 

Steve Addy

Top Post Dawg
Joined
Aug 7, 2002
Location
Iowa
TDI
97 Mk3
I've always heard that the water pump gets changed every other TB job.
IDK of that's really the VW recommendation on these since the WP isn't driven by the TB there's really no threat to the valves / lifters from failure.

IMO I hate to change out a good non-leaking WP since the failure rate on some new ones is pretty high. I installed a Gates WP and it leaked from day one from the driveshaft. Can't say I was too happy about having to go back in and fix that.

Steve
 
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