How not to change out your coolant pipes......

[PKN]

I admit that my first mistake was to start this job when the Cayenne was my only vehicle. My second mistake was to do the job in the driveway with the temps around 90 degrees and the third was not letting the dealer do the work for $1300.

I got off to a bad start two weekends previously when I started the job only to discover that my 2006 TT does not have a radiator drain. I spent a couple of hours trying to convince myself that I just needed to take more parts of the car until I found it and ended up putting it back together.

This weekend I had all of the tools - even a Walmart special canopy to work under. I started by raising the air suspension to get underneath and remove the belly pan. After lowering the car I started the dismantling process. This went reasonably well but I quickly discovered that the plastic emission control pipes are very brittle - especially a "T" piece behind the inlet manifold and one of the re-circulation hoses at the front of the engine, both of which were early casualties. Pretty much everything made of plastic on top and behind the motor were as brittle as a fortune cookie.

Removing the fuel rail and inlet manifold were relatively straight forward except for the fact that I dropped one of the four fuel rail bolts behind the motor - more on this later. The plastic coolant pipes were in good condition. I drilled a quarter inch hole in each pipe and used a $10 hand pump from Walmart to suck coolant out into a bucket. About one gallon or so. An air powered cutting wheel and a beefy screwdriver were used to get most of the old coolant hoses out but all of them left a piece in the thermostat housing or distribution casting. Once again, thanks to advice from this forum, a mallet and screwdriver allowed me to remove the pieces in an hour or so. Most of the small amount of coolant loss (about a pint or so) came from the back center pipe which I believe comes directly from the reservoir. A quart oil container donated its cap which fit very nicely over this rubber pipe to stem the flow.

I uses a dremel with flap wheel to clean up all of the joints the aluminum pipes would mate to, then used a vacuum cleaner and an air line to clean out all of the plastic debris (and most of the spilled coolant). The larger aluminum distribution pipe was a tight fit - I had to shave off about one eighth of an inch of the flange and about a half inch off the rubber connecting hose but got it in by the end of the first day. So far it had taken me about 10 hours and I had dropped about 5 lbs in weight.

The next day I got the three piece pipe in without too much drama but the rubber "O" rings are a tight fit even when lubricated. I took a long hard look at the "T" shaped hose arrangement and decided that it would need a lot more energy and less hand than I had to replace them so I didnt.

I got the plastic clamping plates in place at the back of the motor and then discovered the forementioned broken connector. My neighbor was good enough to run me 10 miles to the nearest autopart store to get a new one which I broke during installation. Another 20 mile round trip and I found a brass version - that won't break. I replaced as much of the hard plastic tubing as I could with small diameter pressure (fuel) hose and re-assembled everything. Remember the missing screw from the fuel rail? First start resulted in the loss of about a pint of gas in a few seconds of cranking from two of the injectors. I searched all over the workshop for a replacement screw and after an hour or so found that the same size screw was used to connect the front panel under the hood. After making sure everything was tight and all injectors were clamped top and bottom I started her. She ran very weak and very rough until I remembered the busted breather pipe. (The one about 4" long top front of the motor). Too late to get a replacement, duct tape came to the temporary rescue and all is well again.

If you do this job on a vehicle 2006 or older, make sure you are prepared to replace any emissions piping you come across. The fancy clip in connectors at the end of many of the breather tubes are also prone to siezure, requiring a small screwdriver to release them. Better still, get the dealer to do it. It took me 20 hours, 10 lbs and I look and feel like I have been hit by a truck....

PKN

[LCE]

Brave man, I have been avoiding this job for the last 12 months, 2003 turbo on 85K so only a mater of time!

[PKN]

You wont get these parts from Halfords, but the weather will be a lot kinder to you. My age is against me too it would have been much easier 20 years ago. My plastic pipes were not brittle at all but the car was first regisered in California and brought recently to Florida so the climate has been very kind. The UK isnt known for wild extremes of temperature so you might just be lucky - (a fellow Brit)

PKN)

[jagman1]

I feel your pain. It took me 20 hours too. It's a ***** of a job. I spent 10 hours replacing the t-fittings at the back of the motor. I broke a breather line too. I spliced the two broken pieces together with some rubber hose.

[globalfun]

Brave man.. Apart from not having the space to work in I would probably not dare...

hm..my 04 CS has about 70 K km, still under warranty last year so hope it brakes before..if not I will just sell the car before the warranty runs out..Spoke to someone else here at the forum, no way of provoking the leak? If the parts crumble when you touch them perhaps a pinch at the right place will trigger this and I can get it replaced.. Not trying to scam here just force nature a bit -)

Edited May 25, 2011 by globalfun

[pcst]

Brave man, that's for sure!

Oh man,,,, I've been waiting to see the complete DIY write up or the Porsche shop manual to tackle this.

Thank got, I have an extra vehicle to run around & won't be doing this on my drive way.

If you know a site with a complete DIY write up or the Porsche shop manual, please let me know, I'm willing to pay $ for 'em.

[the assessor]

I have just completed the job.

My car is a 2004 4.5 non turbo, with lpg conversion, so even more stuff to take off.

the best advice i can give is to take it steady.

don't remove the fuel rail from the inlet manifold it will all come away in one.

take your time and log the parts you remove.

it should take a couple of days for a reasonably competent spanner thrower.

(I own a garage in Leeds so if anyone wants them doing local to me , just get in touch.)

Mick, Oaklands Garage.

01132 577603