Porsche Boxster Water Pump Issue

[onlineformals]

I have a 2005 Boxster S with 17K miles. I purchased the car last April with 13,500 miles.

At around 14K the water pump went out. (bearing sounds and coolant loss)

I had the pump replaced under an aftermarket warranty at my independent Porsche shop. (This shop is highy qualified and very active within the PCA)

Since this time I have been through 4 water pumps. After they replace the pump I will get a small drip out the weep hole and have to add a very small amount of coolant to keep the fill tank in the middle.

This is nothing major - I am talking about 1 bottle of water's worth over the course of a month.

The water pump is OEM and made by Lasco.

Does anybody know of any other pump that is more dependable than the OEM?

Any thoughts or suggestions?

[JFP in PA]

I wouldn't use anything but the OEM pump. We have installed a lot of the OEM's over the years, never had an issue with them failing prematurely, but have seen many aftermarket units crap out in very few miles. Are you sure that the system was properly filled (under vacuum)? Has the car been pressure tested to see if there is any other issues (blown head gasket, cracked head, etc.)?

Edited November 12, 2010 by JFP in PA

[wvicary]

Only use the OEM pumps. I have also installed aftermarket pumps and had some with problems straight out of the box. Some coolant weeping from the pump is considered normal as the mechanical seal uses coolant as lubrication and does not indicate a failed unit.

Sometimes the basics are overlooked and I always start with them. Have the common faults been investigated such as the coolant tank leaking into the trunk area or the correct operation of the cooling fans?

[onlineformals]

I wouldn't use anything but the OEM pump. We have installed a lot of the OEM's over the years, never had an issue with them failing prematurely, but have seen many aftermarket units crap out in very few miles. Are you sure that the system was properly filled (under vacuum)? Has the car been pressure tested to see if there is any other issues (blown head gasket, cracked head, etc.)?

I do not think the car has been pressure tested.

When I first had the car towed to the shop it was obvious the water pump failed. Heard the bearings and then a massive leak.

After the shop replaced the pump they did tell me the system (burps) and I may need to top off the fluid in a day or two.

Again - the thing that I have noticed is a small drip off the center of my skid plate. I had to add a little coolant over the last month, but a very small amount.

Since I am not a mechanic what would happen is the system wasn't filled under vacuum?

I did call another shop today and they told me they have never heard of a pump failing this many times and did suggest I bring it in for a pressure test and to check other things like the fans etc...

[1schoir]

I do not think the car has been pressure tested.

When I first had the car towed to the shop it was obvious the water pump failed. Heard the bearings and then a massive leak.

After the shop replaced the pump they did tell me the system (burps) and I may need to top off the fluid in a day or two.

Again - the thing that I have noticed is a small drip off the center of my skid plate. I had to add a little coolant over the last month, but a very small amount.

Since I am not a mechanic what would happen is the system wasn't filled under vacuum?

I did call another shop today and they told me they have never heard of a pump failing this many times and did suggest I bring it in for a pressure test and to check other things like the fans etc...

If the system was not filled by use of a vacuum tool, you will usually get one or two (or more) "coolant dumps" as the coolant overflows. Sometimes it's forceful enough to overflow the edges of the top of the coolant tank, other times it will just flow down the drain hole that is at about 9 O'clock to the left of the coolant cap and then exit down the drain hose which has its outlet just to the inside of the front of the right rear wheel.

You can help burp the system by driving around for a few days with the silver rectangular lever of the pressure relief valve in the vertical position (click on the photos to enlarge):

It wouldn't hurt to check the underside of your coolant tank for any coolant or caked-on coolant residue, in case the tank has a slight crack or the level sensor under there is leaking:

Regards, Maurice.

Edited November 12, 2010 by 1schoir

[RFM]

The level sensor can not leak Maurice, he has no contact with the cooling water.

[1schoir]

The level sensor can not leak Maurice, he has no contact with the cooling water.

RFM:

Thanks for pointing that out. The coolant level sensor itself has no direct contact with the coolant, but the coolant tank can crack in that hidden area.

Here is a photo of one of my old coolant tanks that sprang a very tiny leak on the corner of the receptacle for the coolant level sensor:

Regards, Maurice.

[RFM]

OK, i see what you meant Maurice, they still have some weaknesses after a certain number of cold/hot cycles.

[onlineformals]

Thanks to everyone for their input.

I took the car to a Porsche master mechanic.

He pressure tested the system, torqued the water pump down and replaced some hoses that had a slight leak and used some screw down clamps.

It's been dry as a bone for the past few days.

[coleta]

RFM,

If the sensor has no contact with the coolant how does it know what the level is?

[JFP in PA]

Black magic.................