overheating after water pump change

[san rensho]

I just changed the WP on my 2004 base and now the temp slowly creeps up and up, no matter if I have the ac on or not. Before i changed the water pump, the temp stayed right next to the 180 hash mark no matter what, It didn't move.

I thought it might be that there's air in the system so forum Guru Meir graciously hooked up his uview to my car and still it overheats. We used the uview when the coolant was hot and full. We couldn't get a vacuum in the green zone of the guage, but it wouild hold vacuumin the red zone. after pulling a vacuum, Meir was able to get the coolant system to pull coolant into the system,. And he did it a couple of times until it wouldn;t take any more coolant. It pulled about 2 quarts of coolant.

After purging with the uview when i'm driving the guage stays between the 180 hash mark and the next mark, about where the zero on 180 is, But if I stop and just let the car idle with the ac off, both fans run on high and the temp won't stabilize. the temp slowly eventually creeps up past the last wihite hash mark on the guage, between the last hash mark and the red hash mark. Durametric shows 120 C coolant temp.

Any Ideas?

[Steve Tinker]

Before anything else, I would ensure that all air has been expelled.
Lift up the pressure relief valve for 2-3 complete heat/cool cycles (cold to running temp back to cold). Just lift the chrome D ring @ the valve and leave it there, then check the coolant level after each cool down period.

[thstone]

Air still in system...

[san rensho]

Originally Posted by Steve Tinker

Before anything else, I would ensure that all air has been expelled.
Lift up the pressure relief valve for 2-3 complete heat/cool cycles (cold to running temp back to cold). Just lift the chrome D ring @ the valve and leave it there, then check the coolant level after each cool down period.

Ive done that several times. Nothing. What used to work was raising the bail when the car was deadcold. It would burp and pick up at least two quarts. But not this time.

[san rensho]

Originally Posted by thstone

Air still in system...

So whats the fix. Drain coolant and refill with uview?

[nicecar]

Had the same problem and read on here to park on decline or back up on ramps and run thru burping cycle. Worked for me. Good luck

[Steve Tinker]

Originally Posted by san rensho

Ive done that several times. Nothing. What used to work was raising the bail when the car was deadcold. It would burp and pick up at least two quarts. But not this time.

San...
Did you drive the car enough to open the thermostat when you flipped the lever open? Usually that takes at least 5 miles before all the coolant starts to circulate -if the thermostat doesn't open fully, the air can still be trapped....
If its not trapped air causing the overheating then it must be something else, like the new water pump you have just installed. I'm assuming that the pump is new and that if you now remove the belt you can turn the pulley and feel the coolant resistance against the impeller.
Stranger things have happened than faulty new pumps.....

[madmodz]

I was overheating too. I accidentally left the bleed lever open for a day while I drove it. That fixed my problem.

[san rensho]

I've driven with the bail wire up for a couple of days and no difference.

One thing i did notice is that when it starts to heat up at idle, if I raise the idle to about 3k, the needle starts to go down.

[Gelbster]

"One thing i did notice is that when it starts to heat up at idle, if I raise the idle to about 3k, the needle starts to go down.[/QUOTE]

Sounds like the w/p is not efficient at low rpm. Had a previous(metal) w/p failure gouged out the crankcase half and caused excessive clearance between the impeller blades and the housing?
Have plastic impeller fragments from a previous failure blocked the system? Try looking in the heat exchanger.

[san rensho]

Originally Posted by Gelbster

"One thing i did notice is that when it starts to heat up at idle, if I raise the idle to about 3k, the needle starts to go down.

Sounds like the w/p is not efficient at low rpm. Had a previous(metal) w/p failure gouged out the crankcase half and caused excessive clearance between the impeller blades and the housing?
Have plastic impeller fragments from a previous failure blocked the system? Try looking in the heat exchanger.[/QUOTE]

The water pump that came out was the original water pump and all of the impellers were perfectly intact. So I can't think that the previous water pump cause any problems. I'm going tobleed the system again with the u view And see if that makes any difference.

[chaiyz]

I still think you've got a big air bubble in the system. Vaccum at the reservoir should help.

[Gelbster]

The only hack you have not tried(??) is to use the UView with the rear of the car up on tall jack stands.Since all else has failed ,why not try it?

[steved0x]

Do you have an under drive pulley on the new car? After I installed my UDP I noticed if I was idling around town the temps would go up, but as long as I was moving (and therefore RPM around 3000 or so) the temps would come right back down.

[nicecar]

Originally Posted by Gelbster

The only hack you have not tried(??) is to use the UView with the rear of the car up on tall jack stands.Since all else has failed ,why not try it?

mentioned in an earlier post that it worked for me however it is ignored sooo....good luck to him

[Gelbster]

Originally Posted by nicecar

mentioned in an earlier post that it worked for me however it is ignored sooo....good luck to him

No, you said "ramps".
I said "Tall jack stands".
Big difference.
You can get another 12"+++ with the jack stands and that extra height is the critical difference.
Ramps are not tall enough. That is why I said "Tall Jack stands".
I use these for my truck but the work well for this specific job on the Boxster:
12 Ton Steel Jack Stands
Don't forget to chock the front wheels really securely! And use two long frame jacks to get the car high enough to place the Tall Jack Stands. Alternatively I use two arms of my ultra sturdy Mohawk lift with the wheel adapters.

[Gelbster]

Wow that is interesting UDP =sub optimal coolant circulation at idle rpm. I have read some hand-wringing about that but never seen a specific instance reported. Thanks for sharing.

[steved0x]

Originally Posted by Gelbster

Wow that is interesting UDP =sub optimal coolant circulation at idle rpm. I have read some hand-wringing about that but never seen a specific instance reported. Thanks for sharing.

To add a data point to my post, I just found out that my left side low speed fan ballast resistor is out. So maybe it is that. But I did notice a difference right away - after the UDP if I am sitting in traffic the temps go up. I don't recall them doing them before the UDP. Anything above just idling and it was fine.

[san rensho]

So no solution yet.

As long as I'm moving and not caning the car hard, temp gage stays around the middle of the guage. But Durametric shows the temp stabalises around 114 Canadian which is kinda high for me.

Then if I stop, leave the car running and turn off the a/c , the high fan never shuts off and the temp creeps up to the last white hash mark on the guage. At that point I turn off the car but it will keep climbing if I kept it running.

I put some UV die in the coolant and at the back of the car where the WP is theres are no leaks but I have lost some coolant, not much.

So the next plan is to take off the spoiler and clean the radiators and take a look at the hoses up front to see if they are leaking.

Another thing I've noticed is that the air coming off the rads doesn't feel really hot hot.

Anyway, thanks all and if you have any ideas I would appreciate it.

[Gelbster]

"but I have lost some coolant, not much"
That could be just a few big bubbles being expelled ?
Cleaning the radiators/condensers - great job !
Remember to modify/relocate the emergency release for Frunk?