Parts Catalog Accessories Catalog Tech Info Tech Forums
 
  Search our site:    
View Recent Cars  |   Cart  | Project List | Order Status | Help    
 >  >
Porsche 911 Carrera Water Pump and Thermostat Replacement
 
Bookmark and Share

Pelican Technical Article:

Porsche 911 Carrera Water Pump and Thermostat Replacement

Time:

2 hours2 hrs

Tab:

$450

Talent:

**

Tools:

Swivel socket set

Applicable Models:

Porsche 996 Carrera models (1999-05)
Porsche 996 Turbo, GT2, GT3 (2001-05)
Porsche 997 Carrera models (2005-12)
Porsche 997 Turbo, GT2, GT3 (2007-13)

Parts Required:

Water pump, thermostat, and gaskets

Hot Tip:

Install the low-temp thermostat for better performance

Performance Gain:

Protects your engine against overheating

Complementary Modification:

Replace radiator hoses

The modern water-cooled Porsches have been known to have troublesome problems with their cooling systems. Two of the principle areas of failure are the thermostat and water pump.

Begin the replacement process by jacking up the car (Pelican Technical Article: Jacking Up Your Porsche 911 Carrera) and removing the lower plastic tray that covers the front part of the engine and the coolant hoses. Disconnect the lower hose that is attached to the water pump (see Figure 4), and let the coolant empty into a five-gallon or larger bucket. If you are replacing your thermostat, too, then now would be a good time to disconnect the hose attached to it as well.

The next step is to gain access to your water pump. This requires the removal of the main belt (see Pelican Technical Article: Replacing Belts on the Porsche 911 Carrera). With the belt removed, the back of your engine should be relatively accessible. Unfortunately, the engine mount bar is still in the way and needs to be removed. Place a floor jack underneath the engine and gently raise it to support the weight of the engine. Don't actually lift the car or the engine, simply place the jack under the lower engine cover until it lightly makes contact. In general, you should never lift the engine from the bottom sump. But for the purposes of simply supporting the weight of the engine while replacing the engine mounts, the cover should suffice (see Figure 1 of Pelican Technical Article: Porsche 911 Engine Mount Replacement). Begin by removing the brackets that hold the catalytic converters to the engine mount bar (Figure 4). Next, loosen the bracket from the engine by removing the nuts shown in Figure 5.

Seven bolts attach the water pump to the engine, and access to some of them may only be achieved from underneath the car. I recommend using a flex 10mm socket to get into the tight spots.

When the engine was assembled, Porsche installed the coolant manifold and the water pump together. Therefore, they use a shared gasket, which you must cut apart in order to remove it from the engine. Figure 2 shows the gasket removed from the water pump housing on the engine, and Figure 3 shows where you must clip it in order to remove it. The new gasket must also be modified prior to installation (see Figure 3). With the pump removed, check the inside bore where the water pump fits for debris or corrosion. With a wire brush, remove any corrosion or debris that may have built up there. Clean off the water pump mounting surface on the engine and install the water pump with the new gasket. Tighten down the bolts to 10 Nm (7 ft-lbs).

At this time, I also recommend that you remove the thermostat housing (located below the water pump) and replace the thermostat as well. The thermostat is a relatively cheap part that can fail quite easily, which leads to your engine overheating. Simply disconnect the thermostat hose if you haven't already, and unbolt the thermostat from the engine. The thermostat used to be sold separately from the thermostat housing, but now Porsche and the aftermarket suppliers simple sell the whole assembly as one integrated unit.

The factory thermostat starts to open at about 187 degrees F (86 degrees C) and only fully opens at almost 210 degrees F (99 degrees C). This means that the engine needs to get very hot before it starts sending its coolant to the front radiators. For this reason, I recommend installing a low-temperature thermostat in place of the factory one. LN Engineering has developed a thermostat that starts opening at 160 degrees F (71 degrees C) and is fully open at about 180 degrees F (82 degrees C). Lower coolant temperatures translate into lower oil temperatures, and the dyno tests that LN Engineering has performed on the cars with the low-temp thermostat installed have revealed a small increase in horsepower (typically about 5 horsepower). It is my guess that Porsche designed the thermostat to open a bit later in order to help the cars run a bit hotter, which typically helps with emissions testing and the burning off of water out of the oil, which can then lead to longer oil change intervals. Installing the low-temp thermostat is a smart idea for engine longevity--it's available for about $175 from PelicanParts.com.

Disconnect the main hose to the thermostat, as indicated by the red arrow.
Figure 1

Disconnect the main hose to the thermostat, as indicated by the red arrow. In order to gain enough clearance to remove the thermostat, you typically need to disconnect the water pump hose shown by the yellow arrow. For the tight spaces near the thermostat, I recommend using a swivel-foot socket (green arrow and lower right inset photo).

Here's what the engine looks like with the water pump removed.
Figure 2

Here's what the engine looks like with the water pump removed. For the 1998-2005 Carreras, you need to cut the old metal seal in order to get it off, as part of it is still trapped in the engine off to the right (it's a dual-purpose gasket). With the new gasket properly trimmed, it should fit into place (lower left).

The water pump seal needs to be trimmed prior to installation (1998â€
Figure 3

The water pump seal needs to be trimmed prior to installation (1998-2005 only). The part off to the right is separate from the water pump and is typically only used when rebuilding an engine. Trim the seal at the yellow marks and use the part on the left. The upper left photo shows a brand new water pump. The lower left shows a new thermostat and seal. The newer-style Carrera thermostat is integrated into its aluminum housing.

The water pump (red arrow) is located next to the crankshaft on the left side of the car.
Figure 4

The water pump (red arrow) is located next to the crankshaft on the left side of the car. In order to remove the pump from the engine, you need to remove the engine mount bar (yellow arrow) from the back of the engine photo.

In order to gain the necessary access to remove the water pump, first loosen the brackets that connect the catalytic converters (green arrows).
Figure 5

In order to gain the necessary access to remove the water pump, first loosen the brackets that connect the catalytic converters (green arrows). Next remove the two bolts that connect the bracket to the engine mount (red arrows). Now loosen but do not completely remove the 15mm bolts on the engine carrier bracket (blue arrow, not all are shown). Finally remove the small M6 centering bolt (Yellow arrow). You should now be able to wiggle / push the bracket out of the way, giving you clearance to remove the water pump.

Install the new thermostat in place using a new gasket (lower left).
Figure 6

Install the new thermostat in place using a new gasket (lower left).

Bookmark and Share
Comments and Suggestions:
rich Comments: hello what's a resonable labor time to remove & replace a water pump on a 2004 Carrera 4s Cabrolet..

appreciate your time... thx Rich
August 27, 2016
  Followup from the Pelican Staff: 2 or 3 hours. - Nick at Pelican Parts  
Riggzee Comments: How often does debris from the worn impeller get in the water jackets of the heads and cause damage? i.e. blocking coolant flow/overheating
July 14, 2016
  Followup from the Pelican Staff: Impossible to say, as not many engines get tear downs when an impeller fails, and who is keeping track anyway? I would say if it came apart, it is jammed in the cooling system somewhere. - Nick at Pelican Parts  
gregor Comments: I just had my '01 996 IMS bearing replaced, along with a bunch of other things. Water pump/thermostat was replaced while engine was out of the car. Shop charged 3 hours labor for this, which seems really high. Anybody have a clue on how many REAL hours this would take with the engine out?
May 4, 2016
  Followup from the Pelican Staff: three hours seems fast.

I don't have any info on what a shop would charge. You can try calling a Porsche specialty shop and asking. - Nick at Pelican Parts
 
zenithblueC2 Comments: Also, what is the correct hose and clamp for the water pump? What model do I order? I have a 99 C2 Carrera. Thanks.
April 23, 2016
  Followup from the Pelican Staff:
I’m not the best with part numbers.

Give our parts specialists a call at 1-888-280-7799. They can figure out what part or repair kit you need.
- Nick at Pelican Parts
 
zenithblueC2 Comments: What size torque wrench do I use? I'm concerned about buying one that won't fit in the very tight space. Also, what is the torque spec when tightening the new pump back in place??
Thanks.
April 23, 2016
  Followup from the Pelican Staff: 1/4 drive for in-lbs. 3/8 drive for ft-lbs. 3/8 should fit in most.- Nick at Pelican Parts  
Blaze-n-James Comments: My 996 had the coolant tank replaced and recently the cap replaced with the redesigned coolant cap... Even though it has over heated a few times. No Leaks, Gadget and Head are fine! What would be your next move considering! Really don't want to pull the water pump and thermostat and find out they are OK! Think I should Jack car up at angle and run motor as it being filled until is gone before installing the new coolant cap. Could I be missing something?
February 24, 2016
  Followup from the Pelican Staff: IS the engine running normal now, or is it still overheating? - Nick at Pelican Parts  
jmj996 Comments: Should I use any gasket sealant on either the water pump or the thermostat housing?
September 21, 2015
  Followup from the Pelican Staff: No, the gaskets will be enough. - Nick at Pelican Parts  
Rich Comments: Is on a 2001 C2 Cab. Seems like the thermostat housing needs to come out to give enough clearance. Ordered a new low temp one anyway. Going to remove the exhaust header to get to the top bolt of the housing. Hoping that nothing else will need to be taken off.
May 14, 2015
  Followup from the Pelican Staff: Yes if your car is a Tiptronic car I have found on a few cars that the thermostat had to be removed. If you can use a wrench instead of a ratchet for the removal of the tightly squeezed in bolt on the thermostat housing you won't have to remove the exhaust manifold. - Casey at Pelican Parts  
Rich Comments: Do you pull the old pump from the top or bottom of the car? I have the pump lose, but can't get the pump out from the bottom or top. Any tricks to this? Have the motor mount plate lose and it still will mot clear.
May 13, 2015
  Followup from the Pelican Staff: WHat vehicle? on a 996 the water pump is removed from the bottom. - Nick at Pelican Parts  
Richierich951&996 Comments: It would be beneficial to also include which bolts are the long bolt positions as well.
February 7, 2015
  Followup from the Pelican Staff: Thanks for the feedback...I remember the first one I ever did, and I wanted to know that too. The long bolts go where the dowels are in the case. - Casey at Pelican Parts  
wildbilly32 Comments: Nick: Thanks. I will be most interested in seeing the failed pump to see if original or replacement. Do the pumps fail to the point where the impeller cavity in the engine could be damaged by a metal impeller or is that just irrational fear? p.s. new to the Porsche family as you can tell!
September 16, 2014
  Followup from the Pelican Staff: I wouldn't sweat the metal one failing that way. I have seen some makes where the shaft fails and the impeller will scrape the water pump housing, but not on Porsche. - Nick at Pelican Parts  
wildbilly32 Comments: Nick: Reason I asked is my 2005 996 C4S just lost the water pump and I noticed the two pumps designated OEM and sold by Pelican show composite. I had my guy order composite from you guys! Did I mess up badly? What's the advantage/disadvantage of the two? New to Porsche and application seems metal could be hazardous in failure as it could compromise the engine block??
September 11, 2014
  Followup from the Pelican Staff: No, not badly. The composite models are fine, they are equipped from Porsche like that. When they come apart, plastic can remain in the engine creating hot spots, so I err on the side of metal ones when available.- Nick at Pelican Parts  
wildbilly32 Comments: Replacement water pump impeller: composite or metal??
September 9, 2014
  Followup from the Pelican Staff: Metal. - Nick at Pelican Parts  
Kenny @ Mars Motoring Comments: If possible it would be great to include the torque spec for the thermostat bolts here as well :
November 23, 2013
  Followup from the Pelican Staff: Coolant thermostat housing to crankcase: 10 Nm (7.5 ft-lb) - Nick at Pelican Parts  
Kenny @ Mars Motoring Comments: That is a nice write up! I do have couple comments that makes the install easier if you don't mind:

1. When remove/install the thermostat, it is actually easier to remove the header and the bolt that holds the coolant line before removing the bolts. Using a swivel-foot socket is a good alternative, but doing so making it close to impossible to tighten it to the spec torque.

2. It is strongly advised to refill coolant back and do a coolant leak test after the water pump, thermostat, and hose install and before putting belts and exhaust back. Doing so would ensure the system is seal, otherwise one would need to spend extra time in removing the per-requiste components again in order to fix the leak from, say water pump or thermostat.
November 23, 2013
  Followup from the Pelican Staff: Thanks for the additional info. We appreciate it. - Nick at Pelican Parts  

  Search our site:    

View Cart & CheckOut | Project List | Order Status |  Help    

 

[Home] [Customer Service] [Shopping Cart] [Project/Wish List]
  [Privacy Statement]  [Contact Us] [About Us] [Shipping] [Careers]

Copyright © Pelican Parts Inc. -    DMCA Registered Agent Contact Page

Page last updated: Wed 12/7/2016 02:32:23 AM