When water pumps attack!
06-12-2010, 02:42 AM
#46
Race Director
OK, No my propeller was fine. The job was done. it took a little more than 8 min like the video shows. But the video is perfect.
BUT I think I know why plastic impeller. I may get flamed for this but I called it as I saw it...
I put the pump on and the impeller was rubbing very slightly against the block.. Ever so slight. I could turn it by hand no problem.. and it even spun a bit when I turned it fast.. Like I said ever so slight... So silly me I pull it back out... Then when I got to looking at the old vs new, I could see where the old pump had rubbed also at one point. So I think this is the way it is designed. I figured a new pump was to rub a little and it would set into place after a min or two of running... and it did. I ran the car for about 2 min. shut it down and took the belt back off and turned the pump and it was fine.... No rub at all.. took the car for 40 mile drive and it was perfect. So I know I have a really tight tollerance in there to get the best pump action possible... Am I crazy or correct.
The job took about 3 hours.. But I did it twice..... I think I could do another in less than 1.5 hrs
BUT I think I know why plastic impeller. I may get flamed for this but I called it as I saw it...
I put the pump on and the impeller was rubbing very slightly against the block.. Ever so slight. I could turn it by hand no problem.. and it even spun a bit when I turned it fast.. Like I said ever so slight... So silly me I pull it back out... Then when I got to looking at the old vs new, I could see where the old pump had rubbed also at one point. So I think this is the way it is designed. I figured a new pump was to rub a little and it would set into place after a min or two of running... and it did. I ran the car for about 2 min. shut it down and took the belt back off and turned the pump and it was fine.... No rub at all.. took the car for 40 mile drive and it was perfect. So I know I have a really tight tollerance in there to get the best pump action possible... Am I crazy or correct.
The job took about 3 hours.. But I did it twice..... I think I could do another in less than 1.5 hrs
Upon looking at the tops of the impeller vanes I see signs the tops were touching the metal of the cavity into which the pump impellter fits. I had the pump replaced at the dealer so I didn't have a chance to look at the engine area where the impeller fit to see if I could spot any signs of the vanes hitting rubbing. Chances are though since it happened so long ago and we're talking plastic vanes now not diamonds any marking has long been removed by the corrosion that erodes the surface of the engine's coolant passages.
Still it is kind of interesting that the vanes would make contact. Should make for a very efficient pumping action to have such a close fit between the vanes and the opposite wall of the pump cavity.
Sincerely,
Macster.
06-12-2010, 05:33 PM
#47
Rennlist Member
Thread Starter
After reading your post I looked at a high res pic of my 02 Boxster's water pump that was replaced at 172K miles. No shaft fracture failure just noisy and a bit of a leak.
Upon looking at the tops of the impeller vanes I see signs the tops were touching the metal of the cavity into which the pump impellter fits. I had the pump replaced at the dealer so I didn't have a chance to look at the engine area where the impeller fit to see if I could spot any signs of the vanes hitting rubbing. Chances are though since it happened so long ago and we're talking plastic vanes now not diamonds any marking has long been removed by the corrosion that erodes the surface of the engine's coolant passages.
Still it is kind of interesting that the vanes would make contact. Should make for a very efficient pumping action to have such a close fit between the vanes and the opposite wall of the pump cavity.
Sincerely,
Macster.
Upon looking at the tops of the impeller vanes I see signs the tops were touching the metal of the cavity into which the pump impellter fits. I had the pump replaced at the dealer so I didn't have a chance to look at the engine area where the impeller fit to see if I could spot any signs of the vanes hitting rubbing. Chances are though since it happened so long ago and we're talking plastic vanes now not diamonds any marking has long been removed by the corrosion that erodes the surface of the engine's coolant passages.
Still it is kind of interesting that the vanes would make contact. Should make for a very efficient pumping action to have such a close fit between the vanes and the opposite wall of the pump cavity.
Sincerely,
Macster.
06-12-2010, 08:35 PM
#49
Poseur
Rennlist Member
Rennlist Member
Don't be suckered in by a mere image of a 997 instrument cluster. The 997 engines run hotter than the gauge reports. They are dumbed down water temperature gauges. The coolant gauge reports water temps at 175ºF well into the the higher temperatures until it finally moves to the max. There is little warning provided.
06-12-2010, 09:43 PM
#50
Race Director
Had coolant changed once around 2006 after I busted a radiator and coolant leaked out.
Then had it changed again when water pump done year or more back. Wait: car has 232K miles now so 60K miles ago... make that 2 years or so back.
Then had some added when coolant tank replaced a few weeks ago. (Not all coolant lost. Tech just had to top up.)
I mean most people aren't going to change the stuff more than once and risking saving a few bucks on some unknown coolant just seems senseless.
Anyhow, I believe the manual calls for phosphate free anti-freeze mixed 50:50 with distilled water. No additives.
Sincerely,
Macster.
06-12-2010, 09:57 PM
#51
Much missed
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My dealer told me they only make the pink coolant now. I topped off my green coolant with some pink when the cap had a leak, maybe 5 oz., and no problems 5k miles later.
