Rotmilky

Finally making my first post here...and already in need of some help. First a bit of backstory-- I'm in the process of restoring two '68 911 long hoods and spend most of my time over at Pelican so I rarely spend time on these forums. Basically I spend 99% of my time restoring the 68 cars--those two are quite the handful. If I see another spot weld that I need to drill out, I think I'll be ill. Anyway, I got tired of welding on my 68 911s and decided it might be nice to actually drive something that (a) starts, (b) has a solid floorboard such that you can't see the road between your feet and (c) doesn't have a heater that looks like a bad Rube Goldberg device. So, I picked up a 997 to drive...and to enjoy the heater and the air conditioner. I found a 2005 Carrera with 60k miles locally. It started and didn't seem to have huge rust holes in the rocker panels--that's enough for me to give it the thumbs up. Wow, she runs like a scalded cat. Amazing car--especially when you're comparing it to the 150ish hp motors that came in the 68. So that's the good part. On the down side, I really don't know much about these cars at all. They're quite different than the air-cooled longs hoods that I'm more familiar with. So, I'm looking for a bit of advice on this. I tried searching but didn't quite find the issue I've got at the moment.

I've owned the car a few months now. Since it's the middle of the winter, she tends to sit in the garage, tucked into her car cover. About every 2 weeks, I start to worry about the battery going dead. I take her out for a 50 mile trip to shake out the cobwebs. Last week, I noticed that she had decided to leak about a cup of 'coolant' onto the floor of the garage. Basically near the rear driver side tire--just below the water pump. I had not driven her in maybe 10 days--so the motor was ambient temperature when the leak started. After leaking a bit of coolant randomly for an hour or so, she just decided to stop leaking again. The motor was still ambient temperature when the leak stopped. Undriven before the leak started and undriven when the leak stopped. Odd. She sits inside an attached garage under a car cover. The temperatures that night weren't really particularly cold outside so I'd expect the temp in the garage to be somewhere around 45-50 degrees F. The location of the leak seems to be the lower part of water pump or maybe the rubber pipe just below it. I tried to upload a photo and it didn't seem to work. Just picture the lower part of the water pump and the rubber hose as being shiny wet. Once the leak stopped, it didn't leak for the next 4-5 days. I didn't drive her during that time. So all these leaking/leak stoppage happened on a cool motor that didn't move at all during the entire duration of the leak. The weather during this time outside and inside the garage were not changing drastically. I finally decided to take her out to see if heating the motor up would case the leak to spring again. Drove her 50 miles. No leak. Tube and water pump exterior is now dry.

Anyway, I've read that the water pumps can be a bit dodgy on the 997.1 models. Is there a way to tell if the leak is coming from the water pump or from the tube? Is there a way to tell if the water pump is original or if it's been replaced? My thought at the moment is to pick up a new water pump and install it just to be safe. Thought I might get a 2nd, and 3rd, and 4th opinion to see if people who knew more about these cars than I do agree with that.

A 2nd oddity was that the liquid coming out was orange-ish. I suspect that it should be green coolant color, although I admit I don't know what 'Porsche coolant' should look like. The air cooled motors don't bother with that watery coolant. They're perfectly content with something like twice the amount of oil the 997 needs...and a splash of air. So, yea, I don't know what color it should be. I suspect that the coolant needs to be flushed and refilled. I haven't gotten to that yet, but plan to in the next few weeks.

Thanks,

V.H. Whitley
Los Alamos, NM

acao

Probably the water pump. My coolant is pink.

Macster

A water pump can fail at any time. Most wait a while.

There should be no coolant leak. Now about that hose I'm not sure what you are talking about. AFAIK there is no overflow tube or hose to direct any coolant overflow because there should not be any. The cooling system is intended to be sealed to hold/retain pressure as the coolant gets hot. It is this pressure that prevents the hot (I've observed it reach ~226F under extreme conditions) coolant from flashing to steam with potentially expensive ramifications.

It might be -- this is more a WAG than anything -- it might be, it could be the heater core or a hose or a fitting is leaking coolant and this is running down the drain hose the carries any water that can collect in the heater/AC regions, that could even be from the A/C evaporator which can develop a goodly amount of condensation under some conditions. We've all seen and probably been scared by the sometimes large puddle of what proves to be plain old water under our car after shutting it off after a drive in hot weather and the A/C was on.

You need to know for sure. It is not much fun to replace the water pump if it is not needed. However, it is risky to continue to drive the car if the water pump is leaking and from your description leaking pretty bad.

Oh, how to tell...

Well, you can thoroughly rinse the area -- you can use Simple Green or something similar (a mild detergent) to help remove dirt, grime, any coolant residue, then start the engine let it idle and get warm. It probably won't get warm enough just idling so you'll have to drive the car around. Avoid using the A/C as this causes the radiator fans to run which keeps the engine cooler.

Ideally you'd like these to come on on their own because this tells you the coolant is at 212F.

As soon as the fans come on shut off the engine. Raise the car. With considerable caution get under the car and observe the water pump / hose areas and try to note where the coolant appears first, if it appears at all.

To know if the water pump is original... Often when a car, in this case an engine is assembled the assembler marks the engine in various ways -- a paint pencil for instance -- putting a blob/dap of paint of a certain color on fasteners as he finishes the final tightening sequence, or in the case of the water pump when the bolts are tightened. This is a way to help him not miss anything and if at final check out the water pump leaks the color of the paint tells the manager who might be responsible.

If you know what these water pump bolts look like on an engine that is as it came from the factory you might be able to spot signs the water pump bolts have been disturbed because someone was at them with a wrench.

In other cases you can note the bolt heads are a bit chewed up, so signs of having been loosened. In the factory they are only tightened.

Another tell tale is sealant having been slopped on the water pump gasket, or non-factory hose clamps used or signs the hoses/clamps having been disturbed.

Rotmilky

Thanks for the replies.

Let me try to attach a photo again of the area that I found to be wet showing the black tube I was talking about:


That area is on the lower driver side part of the motor that is where I think the leak occurred. The photo was taken from the rear of the car. The serpentine belt makes a pass over what I'm assuming to be the water pump just above the wet area. However, I don't know what a water pump is supposed to look like on a Porsche motor. As I said before, the air cooled motors don't have a water pump.

I was going to order the Porsche Workshop Manuals to help guide me through changing out the water pump. I've found the manuals to be extremely useful for the 68. However it seems that everything is online these days and needs to be accessed through PIWIS. <Shrug> I turned up a nice descriptive thread here that I think will suffice as a guide to change out the water pump. https://rennlist.com/forums/997-foru...-part-1-a.html Looks like i'll order the parts and change both the pump and the coolant tube just to be safe.

BED997

There was, I believe a coolant color change sometime around 2006ish. The current color is redish-orange.

Check here for some coolant (no affiliation) and replacement parts. They say Porsche coolants can be mixed regardless of color...

http://www.suncoastparts.com/product..._Enginecoolant

USMC_DS1

That's the right color for the coolant... pink or red/orange for some. I wonder if someone attempted a WP replacement but did not torque all the screws properly then you'll get leaks over time. It's a very tight area to get into with a torque wrench so I can easily see a mech and/or DIYer cutting corners during this process. Here are two DIY posting which may give you some insight. https://rennlist.com/forums/997-foru...-part-1-a.html or https://rennlist.com/forums/997-foru...placement.html

You may want to just check the torque value off each of the 7 screws on the WP. Checking the torque values of the WP screws would be the cheapest approach parts cost wise but at that point you've already done 1/2 the work... I believe suncoastparts may still have the WP listed for ~$250 if you want to replace it. YMMV but the WP's are known to give up at ~45K miles or sooner... GL and let us know what you find.

Macster

Based on the photo it looks like the water pump is leaking. The fluid comes from behind the pulley.

You do have to check/look *above* the water pump to make sure the leak isn't higher up. What it could be from I do not know but above the water pump wants to be dry and dusty.

The hose is wet from the coolant from the leaking pump.

You can replace the hose if you want, of course.

Be sure you test the old and new T-stat in hot water on the stove to ensure the new T-stat opens at its rated temperature. You can compare too the amount the new and old T-stat open.

plau

the black hose attached to the thermostat which attached to the water pump,the first thing to hope for is the hose,if not change the water pump and remember to change the thermostat gasket,very good diy piece here in rennlist.i changed mine lst week in my 06 (30,000),the wp started to make noise.good luck