water pump/idler pulleys issues? What say you?

Hello all. So not long ago I noticed my coolant light flashing. It would also happen only after the 2nd time I drove the day (that day, after warm). Noticed my coolant was a tad low , so I refilled w/ distilled water and kept on trucking. So a week or two later, same problemo- filled her up a bit more and now it has kept steadly past few weeks. I also would sometimes hear a bearing-going-bad type sound at start ups sometimes comming from the water pump area. I noticed no coolant leaks anywhere. (100% positive it's not the SAI) So small coolant leak+ whiny-bearing sound from WP area + Car is at 119xxx miles (right on schedule for WP replacement) So I automatically assumed water pump going bad, so I ordered a genuine Porsche pump & coolant from the good folks at Sunset. Well today I begain to perform the work. I removed the belt , and noticed that the water pump bearing feels smooth, the pump looks very clean (pretty sure it's been replaced before) no visible leaks, and makes no noise when spun. However my idler pulleys and tension are very chatty. I included a short 20 sec. video-maby you guys can confirm what I suspect. Might as well replace all 3 right? Could it be these pulleys that were fooling me into thinking it was the pump. Or could the WP bearing be going bad lil by lil and only noisy sometimes? Should I run the engine to confirm the noise? Or would the MaF not plugged in cause a CEL that I won't be able to remove later w/o OBDII scanner? To watch the video just click the top blue bar where it says "photobucket" . Sorry I couldent figure out how to imbed it. http://i45.photobucket.com/albums/f80/kickassskater01/Mobile%20Uploads/3CBDD620-B2EE-4692-80F4-EB38F4C3C561.mp4 Regarding the water pump? What do you guys think ? Should I replace the pump anyways since I already bought it as PM? Wait for the existing pump to start getting noisy or leak before I replace (I'm not a fan of fixing what's not broke, especially things that can leak). On the carfax report it shows its last "Maintenece inspection completed" at 93,2xx on 6/30/12 at woodland hills auto gallery. Last shown vehicle service was @ 80,2xxx Beverly hills Porsche bout 4 yrs ago- but dose not specify what was done. I'm wondering if the pump has been already replaced. Car is at 119xxx now. The question still remains where the coolant is getting lost. I found this hose that I find very suspicious . All that build-up is pink. I haven't driven the car for the last week, for fear the water pump might fail and the last thing I wanna do is overheat the heads or destroy that impeller into pieces. I don't plan to drive until the pulleys are fixed- but how risky would it be driving the car around town like that? Any help, advice , is appreciated

For sure replace the pully(s) and tensioner that are marginal. If you cant verify that the WP has been previously replaced, I think it makes sense to do it now. As far as starting the car without the drive belt attached, you would probably find that the pully noise you heard before is absent, but you still wouldn't know whether it is the pulleys or the WP that were making noise. I don't believe starting without the MAF attached will throw a code that cant be cleared. The car may not idle well though.

You have the water pump, why wouldn't you just replace it? Better to know for sure than perpetually worry. The pulleys should spin smoothly and without noise. If they are suspect, do them while you're in there. I would be more concerned about where your coolant is going.

Have you looked at the AOS, or the overflow tank? The part you showed in the first picture is about a 7 dollar part, and they are prone to breaking, you can either order a new one, or go to Home Depot and get a brass piece that will fit between the two hoses, than zip tie it to the bolt that held the original plastic part in place. If you do want to get the original part, the part number is on the plastic piece.

Quotes source post: 11874616

Sorry I must have worded it incorrectly, I meant running the engine w/ the drive belt on (but w/o air box & MaF) Figured if it's not broke then why fix (the pump) but maby I will just go it to get it out of the way, though I'll probably wait till the new pulleys come in to do it all at once. Also noticed the video doesn't work unless you click where it says "photobucket" on the top blue bar. Thank you guys.

Couple of things. You have a new water pump and you can use this to judge if the "old" one has too much play. Another sign of a worn accessory drive is the belt develops a sharp edge as it makes contact with the side of the pulley. It does this because the accessory drive has too much bearing play and this allows the pulley to get out of alignment. The water pump may still have no play but still be bad. But it should show signs of a leak. If you see dried anti-freeze residue on the water pump housing that's a good sign the pump is bad. Idler/tensioner roller bearings can go bad at any time. While the ones in my Boxster (288K miles) haven't gone bad the ones in my 03 Turbo (125K miles) have had to be replaced twice now. If there is no sign of a leak at the water pump the coolant leak can be anywhere. Most common locations are the coolant cap and the tank. However, that picture of that hose "fitting" sure looks suspicious and I'd address that regardless. Then check the cap. Unless the cap is new I'd just replace it. Be sure you clean the tank cap threads off and where the cap seats against real good. Be sure you put the cap on properly and tighten it down correctly. Keep an eye on the level. If it continues to drop then there is a leak. The coolant tank has to be suspect or if you haven't been diligent on keeping the trash out of the radiator ducts suspect a radiator leak. Oh yeah, and with the 996 the AOS can develop a coolant leak too. Which reminds me: Be sure you clean the car of all that plant trash and check the body water drains. I bet you'll find they are full of leaves and such. This stuff can develop a foul odor, but even worse it can cause water to back up and overflow into the cabin and this can cost you a lot of hair pulling and a very expensive security module.

The first sign of my water pump failing was not a noise but a tell tail egg cup of water on the garage floor.This was a DIY job of mine at 70,000 miles. The actual pump looked dry but the water was directly under the pump on the garage floor. I could not feel any play in the pulley but it did give out a slight scrape noise when I spun it. Nothing like as free as the new one. However, in your case, I would be more concerned in changing the hose before the pump. Also change the other 2 noisy pulley's. Check your belt if it shows wear. Keep an eye on the coolant level. If it still looses then change the pump. The Pump DIY was not easy. It's a fiddly time consuming job with the bolts. I would at least leave it until next summer when I could work in warmer weather. Be very careful when removing the 7 pump bolts as 2 of them are longer than the others and need to go back in the correct order. No need for any sealant on the gasket. Make sure you clean both flanges and do not over tighten the bolts. I also changed to the low temp thermostat at the same time.

That fitting is plastic. Be ready for it to "disintegrate" if you touch it. Many of us have replaced it with a 1/4" brass double barb fitting. You can drill out the integral plastic engine bracket to allow the brass fitting to pass through before you put the hose on. check this post: https://rennlist.com/forums/996-foru...e-is-this.html

Proactively replaced water pump and low temp stat. Very glad that I did. Preparing to take the car to the track, so also installed a 3rd radiator. After I replaced the water pump, noticed the inside fins were starting to deteriorate. Excellence magazine published an article talking about how time, not miles, actually is the determining factor for these stock water pumps to be replaced. I ordered an OEM pump that has a composite material for the fins inside that I am hoping will last longer. The original stock OEM water pump fins seemed to be made out of a simple plastic material, I am guessing came from the factory in 99. With new coolant, low temp stat, new water pump, and the 3rd radiator, I am now noticing a huge difference in being able to drive the car hard and for the cooling system to keep up. I don't think the coolant should be left in the car for "lifetime", and am going to do a coolant flush every 3-4 years depending on how hard the car is driven and # of track days. Maybe every 4-5 years, but not lifetime Any others had luck with the 3rd radiator/water pump/low temp stat mod and really notice a benefit from the car being able to cool more efficiently when driving hard?

Quotes source post: 12224468

I replaced my pump at 65k - no noise but I was getting significant coolant leak after a hard run. Before that I had minor leak that was not visible at front of engine (back of car) - turned out to be oil cooler o-ring which you should be able to see on a lift - I chnaged that when I did rms and aos (and ims while in there) ...if you are not sure when wp was replaced - good idea to do preventative on that plus thermostat ...