Cayman / Boxster Cooling System Reliability Improvement


Cayman / Boxster Cooling System Reliability Improvement

Posted: Monday, December 22nd, 2014, 1:15 AM

Much ado has been made of the Porsche M96 / M97 IMS bearing issues.  But it is often overlooked that the cooling systems on these impressive little cars is also a sore spot.  

Many a Boxster and Cayman owner have walked out to their babies only to find a puddle of pink fluid on the garage floor.  Uh oh... what do I do now?  Well, more than likely your waterpump has gone into failure mode.  You may have heard the grinding or you may have had the tunes turned up a little too loud to really notice.  The performance of the engine didn't change, but the telltale sign of a leaky waterpump is there.  You really don't want to drive the car any further after you have found coolant on the floor.  We recommend you call your local service shop and ask them for the best way to get it to them for some needed TLC, or maybe you are going to jack it up and tackle it yourself!  Either way, here are a few things for you to consider as you tackle this endeavor (there are a ton of DIY articles on the web, if you are tackling this job yourself, go ahead and Google the procedure):

1.  The latest and greatest pump starts with a 997 part number and is Rev. 5 (as of Dec 2014).  Make sure you are installing the latest revision of the waterpump design possible.  Porsche spends a ton of money making sure they get the engineering as close to perfect as possible.  You should take advantage of this.  Revisions are very expensive and Porsche only makes them when deemed necessary.  If you have a choice, let someone else deal with the older version of the pump and ask your service provider to ensure you have the latest.  BreitWerks only uses original equipment (OE) parts that are fresh stock from the Porsche warehouse. 

2.  Insist on Porsche brand coolant.  Porsche states that there are additives in their coolant that help to extend the life of the pump.  It will cost you a little more, but this is an area where an extra $25 or so really should be considered.  A 50/50 mix of the Porsche coolant and distilled water will work for most of the US.  You may need a 60/40 mix if you are in an extremely cold area.  As far as the distilled water, insist on it!  Hose water can have many impurities that will contaminate your very expensive OE coolant so for a few dollars more, a few gallons of true distilled water is extra insurance.

3.  Now is a good time to change your drive belt.  You have to have it removed anyway to R&R the waterpump so you might as well put a fresh belt on there.

4.  There are three main hoses that need to be removed while replacing the waterpump.  Now is a good time to consider changing these hoses.  Take a look at the ends of the hoses and assess their condition.  For less than $100 you can have all three hoses replaced with brand new rubber!  When replacing hoses, it is also a good idea to replace the squeeze clamps.  I have had more than one old squeeze clamp that decided it did not like it's new hose partner and failed to place proper pressure on the joint.

4.  If you are doing it yourself, take your time and be sure to torque all of the bolts on the waterpump mount to the factory specified torque values.  These pumps already have enough problems.  No need to introduce additional stress on the pump by warping the mounting surface with improper torques.  If you are having it done by someone else, ask them if they torque the bolts!

5.  This is also a good time to consider a change to a lower temp thermostat.  While certainly not required, it may give your motor, with your particular driving style, just a little extra added insurance.

I lived through the 944 era of Porsche's first real try at water cooling.  944 waterpumps were notorious for failing.  It took years before they figured out that the turbo version of the pump was sufficiently robust enough to last many, many more miles than the original design.  Hopefully revision 5 is the last revision that Porsche will have to make to the M96 / M97 waterpump!

As always, if you have any questions, give us a call at 321-806-8664!


Back to Breit-Blog