When water pumps attack!
06-10-2010, 11:47 PM
#32
Rennlist Member
Thread Starter
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
06-10-2010, 11:56 PM
#33
Rennlist Member
Was your original impeller plastic or metal? Sounds like the new one was plastic??
I wonder if the Boxster metal replacement mentioned earlier was tight enough to scuff the block?
I wonder if the Boxster metal replacement mentioned earlier was tight enough to scuff the block?
06-11-2010, 09:02 AM
#34
Rennlist Member
Thread Starter
Both are plastic.. I am not saying what I did was correct. But it did all seem to make sense after I got looking at things.
06-11-2010, 10:38 AM
#35
Parts Specialist
Rennlist Member
Rennlist Member
Jake can answer that best - BUT for me, the plan was to look in there (since its open while doing the retrofit) and see if there was anything I could tell, then decide to replace if available.
You can just set the motor to TCD and pull the tensioner and have a look too....if you saw the 2 parts (LNE's and OEM) on a bench side by side you would be shocked and in wonderment as to why the OEM part is in your car.
(sorry guys, just the truth)
I hope that Q was about the arm and not the WP.... if for the waterpump, I would not replace as a preventative item, Jake may have a differant opinion and maybe after hearing his I could be pursuaded to re-think my opinion) - I am easily swayed these days
06-11-2010, 12:49 PM
#38
sbpsu354:
"I've noticed that the water temp in my 997 hits the 175 mark and then the needle never moves from there."
If you look closely at the gauge you will see a small pin at the 175 mark. If you overheat a 997 you could bend the needle as it tries to pass that pin.
Wonder if Jake and 1999porsche911 know about this? I wonder how they keep the temp below the 180 thermostat? Porsche surly would not believe that a lower temp T- stat could help lower the operating temp? The 997 fans must run on high speed all of the time.
"I've noticed that the water temp in my 997 hits the 175 mark and then the needle never moves from there."
If you look closely at the gauge you will see a small pin at the 175 mark. If you overheat a 997 you could bend the needle as it tries to pass that pin.
Wonder if Jake and 1999porsche911 know about this? I wonder how they keep the temp below the 180 thermostat? Porsche surly would not believe that a lower temp T- stat could help lower the operating temp? The 997 fans must run on high speed all of the time.
06-11-2010, 12:56 PM
#39
Burning Brakes
06-11-2010, 02:57 PM
#40
Rennlist Member
Thread Starter
To remove the rear engine brace would have taken removing the exhaust. Just and FYI
06-11-2010, 04:03 PM
#42
06-11-2010, 10:10 PM
#45
7th Gear
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After I installed the pump I spun it by hand and it was indeed hitting about every 180 degrees, so twice per revolution.I moved the pulley back and forth over the contact points to "mark up" the offending impeller blades. I then removed the pump to have a look-see and sure enough I could see where two of the blades were making contact.I gently filed down a little meat on each one and reinstalled, Perfect! With that being said I am going to replace the w/p on my 996 because of age and mileage 99' w/90k It looks to be the original pump.My thinking is to go w/ the oem plastic impeller pump and if there is any interference I can file those blades as well.It's a fine line.Plastic impeller= blocked cooling capillaries or Metal impeller= Your own mini milling machine (If the the bearing fails) I choose Plastic!!