2006 GTI SE Problem -- High RPM, low speed

[jtm]

Our 2006 GTI SE with 100 hours is experiencing higher than normal RPM (+500 RPM) and lower than normal speed (- 10 MPH and decreasing). One mechanic wants to replace the pump based on this description. Any other thoughts on possible causes?

 

[thejacksonkid910]

check the wear ring. and also check the impeller to see if its mushroomed or torn up? sounds like a wear ring though

 

[jtm]

Thanks for the quick and helpful response. The wear ring looks like it has been machined by the impeller. The impeller is not damaged, but about six vanes are broken. I think the housing needs replaced.

 

[thejacksonkid910]

no prob. if the distance between the ends of the blades of the impeller and the wear ring (which goes around the impeller is more than the thickness of a dime than it will need to be replaced also. (and or if it has deep gashes) this will allow enough water to go around the impeller that you will lose the power of the pump.

 

[thejacksonkid910]

also if the vanes of the impeller are broken, it will also need to be replaced. im gonna give you the benifit of the doubt and say if YOU say you need a new housing . get one