Coolant expansion tank split pics

[akt4rgtr 0]

Hi,

I'm new to this website and new to Porsche ownership and was hoping that I could get some help with an issue that's just occurred with the coolant expansion tank of my 04 Cayenne Turbo.

I recently purchased this vehicle back in June after selling my range rover. At the time I did quite a bit of research and discovered the issues with the coolant pipes, carden shaft bush, ignition coils etc that were prevalent with the early Cayenne models. After viewing a few vehicles that were less than desirable I eventually found a Cayenne in pristine condition, and more importantly with all the aforementioned work carried out by the dealer. I've been using the Cayenne everyday since and can not fault it.

Yesterday as I arrived home I heard a loud popping type noise when I was parking the vehicle. After stepping out I noticed a pool of fluid on the floor, located at the right hand side of the vehicle. On inspection I realised that it was coolant fluid and refiled the expansion tank to try and locate the leak. At first I thought it might have been one of the rubber hoses in and around that area. After removing the airbox to gain access to the area I found that it was the expansion tank that had split (see pics below).

Is this a common problem with the cayennes and has anyone else had this issue? I've got to say that I expected a lot more from prestige manufacturer such as Porsche. The expansion tank was only manufactured in Sept 2003 and it should really last the lifetime of the vehicle!!

Now, this is were I need your help; I've ordered the part and should get round to fitting it this weekend. Can anyone tell me if the cayenne has a bleed screw of some description and if so where is it located? What is the process for refilling the coolant?

[JFP in PA 694]

Like most OEM's Porsche prefers to refill these systems under vacuum to eliminate any air pockets, which can be very problematic in alloy cased and headed engines. Some DIY'ers say that you can do it without vacuum, but the vacuum system leak tests the entire system, refills the system, prevents any retained air, does it all in about 5 min., and does not require any future coolant level top up, so it is hard to argue with. We use vacuum on literally everything that comes through the shop. We premix the Porsche OEM coolant (only) with equal amounts of distilled water (only), then refill the system.

The vacuum tool will cost you about $100, as long as you do not buy it from Porsche...........

[wvicary 87]

This is not a common problem on the Cayenne and yours is the first I have seen. There is no bleed valve on the Cayenne and they do self bleed through the expansion tank rather well. I would also verify operation of the thermostat, cooling fans and that the water pump is actually circulating coolant and doesn't have a damaged impeller.

[akt4rgtr 0]

Like most OEM's Porsche prefers to refill these systems under vacuum to eliminate any air pockets, which can be very problematic in alloy cased and headed engines. Some DIY'ers say that you can do it without vacuum, but the vacuum system leak tests the entire system, refills the system, prevents any retained air, does it all in about 5 min., and does not require any future coolant level top up, so it is hard to argue with. We use vacuum on literally everything that comes through the shop. We premix the Porsche OEM coolant (only) with equal amounts of distilled water (only), then refill the system.

The vacuum tool will cost you about $100, as long as you do not buy it from Porsche...........

Thanks for the advise, do you have a link for this tool? Looking at the design of the expansion tank this tool should also work on other VW/Audi/Porsche Vehicles?

This is not a common problem on the Cayenne and yours is the first I have seen. There is no bleed valve on the Cayenne and they do self bleed through the expansion tank rather well. I would also verify operation of the thermostat, cooling fans and that the water pump is actually circulating coolant and doesn't have a damaged impeller.

Thanks for the advise. There car didn't appear to be overheating when the expansion tank failure occurred and has been running fine without any issue for the last few months until now. Where is the thermostat located on the engine and is it easy to get to? Any pics or workshop diagram would be very helpful.

[Loren 2,334]

http://astore.amazon.com/renntechorg-20/detail/B0002SRH5G

[JFP in PA 694]

The link Loren provided is for the unit that includes adaptors for everything from lawn tractors and motorcycles to your Porsche; we use the UView tools on literally every water cooled vehicle that comes into the shop.

[akt4rgtr 0]

http://astore.amazon...tail/B0002SRH5G

The link Loren provided is for the unit that includes adaptors for everything from lawn tractors and motorcycles to your Porsche; we use the UView tools on literally every water cooled vehicle that comes into the shop.

Thanks for the link. Don't think I'll have this by the weekend but may just buy one as it seems a good tool to have.

[wvicary 87]

They are a very good tool and highly recommended.

[TTLee 0]

How on earth do you remove the coolant tank ?????

I've removed the air filter housing and the plastics around it but can't see where the coolant tank is bolted in

Mine is a 2005 cayenne tt thanks in advance

[hahnmgh63 32]

My Coolant tank also split at the friction welded seam last fall. The parts guy at Sonnen said he had sold quite a few of them and that he stocked extras becaue of the volume of sales. The part # was superseded so we thought that Porsche may have improved the original part.

[akt4rgtr 0]

How on earth do you remove the coolant tank ?????

I've removed the air filter housing and the plastics around it but can't see where the coolant tank is bolted in

Mine is a 2005 cayenne tt thanks in advance

I have the split expansion tank in my office. I can take some pics of back and underside to show the mounting locations.

IIRC I think we had to remove the entire airbox to gain access to the expansion tank? My brother was the one who did most of the work, so I'll ask him.

Edited April 14, 2012 by akt4rgtr

[hahnmgh63 32]

To remove the Coolant tank it is in the service manual. You remove the bolt that can be seen by the Engine Tq. arm (may be easier with Tq Arm removed from body side and swung out of the way. Then you need to remove the right headlight to access the larger holding bolt with a socket & extension. Then there are the two hoses that need to be un-clamped when you get it loose.

[woodslayer 0]

do check your cooling system... when my cooling tank went is was due to a faulty waterpump... Hard to work out as the motor ran a little warm but no too hot.. finally worked it out but wasted a week messing with it after work.

[jonsmiff 0]

my header tank on my 2006 turbo s has split in the same place, it is not necessary to remove a headlight to remove the tank.

[voodoocat 2]

To remove the Coolant tank it is in the service manual. You remove the bolt that can be seen by the Engine Tq. arm (may be easier with Tq Arm removed from body side and swung out of the way. Then you need to remove the right headlight to access the larger holding bolt with a socket & extension. Then there are the two hoses that need to be un-clamped when you get it loose.

I had the same problem, a slow leak at bottom of expansion tank and coolant ran down with a small puddle near right front suspension. I first thought it was trx fld because it's red, but coolant. Need to remove bracket that hold the to arm, and need HL out to access the 2nd bolt. Just loosen and swing up the tq arm no need to remove. It holds almost a gallon so order Porsche coolant (and new tank cap) when ordering the tank.

Edited May 28, 2012 by voodoocat

[stevie s 1]

I have also experienced this over the weekend. Took it to Porsche in Walnut Creek and am being charged $670 to replace.

[stevie s 1]

Forgot to mention that I have an '05 Cayenne Turbo with 67K miles.

[hahnmgh63 32]

Sorry to hear the cost stevie s, the tank itself new from Porsche is only around $50 and is fairly easy to swap out.

[stevie s 1]

hahnmgh63, wish I had known but when I saw coolant leaking, I thought it was the coolant pipes and figured that I needed to get it to the shop right away. I try to DIY as much as I can.

[hahnmgh63 32]

I thought the same thing when I saw mine as my Coolant pipes were done but they didn't do the Plastic "T's at the time but after doing a little looking around discovered it was just the Coolant tank thankfully, what a relief.

[royxaxa 4]

mine was actually cracked on the bottom after i replaced the pipes and the T and I thought the T went off again LOL

[Davern1 0]

My expansion tank just blew up last weekend while I was pulling my Airstream up a long, hot grade in the Eastern Sierras. I had had the water pump changed two weeks prior due to a leak. I pulled over within a mile and the car overheated. Had it towed to a local mechanic in the area who replaced the expansion tank and now has found a leak in the water pump that was just replaced. He thinks the new water pump was defective and probably leaking which built up too much pressure and blew the tank. It was completely in two pieces. Any thoughts?

[wvicary 87]

Was it a OEM pump?

[Davern1 0]

Yes, it was new OEM pump. Fuel pump was also found to be bad after putting the cooling system back together. I wonder if the fuel pump started failing on the grade, the engine leaned out which quickly raised the pressure and then it blew the expansion tank and seal on the water pump?

[deilenberger 34]

I'd be looking at replacing your reservoir cap. It has a pressure relief in it to avoid that sort of problem. It's also cheap - any car parts store has one for about $7.. (it's a common VW part..)