Coolant pipe corrosion

[Rs6Rob]

Do the coolant pipes under the front right wing corrode from the inside out or outside in?

I took the car drag racing on Thursday evening, after 4 runs I was waiting in the holding area and I could smell coolant and I noticed some steam. Switched the car straight off, the temp hadn't gone above normal and it didn't indicate low coolant. There were small dips of coolant from the under tray and it also looked wet inside the right front wheel arch, but it wasn't pissing out everywhere.

Got it recovered home and when I took it off the recovery truck there was a puddle left on the truck and it was now showing low coolant, I haven't had a chance to get it jacked up and start trying to find the leak. Hopefully its just going to be a loose clip or something - as it didn't dump the coolant it is going to be a small leak.

I have always dismissed the coolant pipe problem as I live in Dubai and just assumed they rotted from the outside in due to salt etc that you have on the roads in the UK.

[IanH755]

Outside in but there's a section where, even if the rest of the pipe looks OK, it'll rust extremely badly just under a clip - see these pics - viewtopic.php?f=47&t=122918&hilit=coolant+rust#p823821

[Jim Haseltine]

Doesn't need salt. The OE coating is poor to say the least - when I took my new pipes to be powder coated the guy took one look at them and said "It won't take long to strip this stuff off" and he was right - about 30 seconds in his stripping bath had them as clean as a whistle.

[DRN]

How much does it cost to get these pipes replaced and who does a good job, thank you.

[IanH755]

It depends on where about's you are in the country as to who is best for you to use but my current preference for any mechanical work is either Grizz at Unit20 near Ellesmere Port or Ricky at REPerformance in Swindon, however the actual work isn't that difficult for most garages to do to be fair as the current fix is to just chop out the rusty section and replace it with a new flexible bit then seal it all back up (which is what Grizz etc does) as a "cut/paste" fix.

I think MRC were one of the last well known indpendants to say, "no we'll replace the whole pipe instead" but even they may now have swapped to the cut/paste fix.

The cost for the cut/paste fix should be under £300 but the pipe replacement is big bucks as the engine needs to come out, hence the much more common cut/paste fix.

[Jim Haseltine]

It is possible to replace the pipes without removing the engine but it's a very awkward (and long, unless you're lucky) job and again unless you're lucky, cause slightly more than superficial injury* to the person doing the job. It took me around 50 hours spread over 5 days (including an oil change) - one day I only managed about 3 hours work because I was working outside with it raining on and off for most of the day. If I had gone about the job differently I could probably have knocked 8 hours off that total. A long flexible head 1/4 or 3/8 ratchet would have made dealing with a retaining bolt easier too.
A fair amount of time was spent trying to work out how to get to things so if I ever have to do it again (and I hope not) I suspect it'd be down to around 30 hours.
Anybody contemplating diy replacement:
1. you need to be stubborn. Very stubborn.
2. you need to be tall enough to be able to stand by the rh wheel arch and reach down behind the left hand side of the oil filter bracket with your left hand
3. you'll need relatively slim forearms and still be prepared to cut yourself to ribbons
4. you need to be able to spend a fair amount of time working by feel alone whilst trying to picture what you're doing
5. you need to be flexible in your approach and MacGyver some tools
6. you need to be stubborn. yes, I know this is point 1, but you really, really need to be stubborn
7. you have to have a plan in case the job goes tits up after you've got beyond the point of no return

What helped me was to repeat a mantra - "30 hours at Audi rates".

Two very useful tools - a magnetic pickup tool and a reel of strimmer cable. The pickup tool so you don't drop bolts you're removing and the cable to tie to tools in case you drop them into the engine compartment - and trust me, you WILL drop tools - luckily, the only one I dropped that wasn't tied fell all the way to the downpipe and I was able to reach it from below.

*it took over a week for the lacerations on my left arm and hand to heal. I suspect I'll carry the scars for the rest of my life.

Additional:
Was it the worst job I've ever done on a car? Probably not, but it's right up there near the top of the list.

[douglas96]

It is possible to replace the pipes without removing the engine but it's a very awkward (and long, unless you're lucky) job and again unless you're lucky, cause slightly more than superficial injury* to the person doing the job. It took me around 50 hours spread over 5 days (including an oil change) - one day I only managed about 3 hours work because I was working outside with it raining on and off for most of the day. If I had gone about the job differently I could probably have knocked 8 hours off that total. A long flexible head 1/4 or 3/8 ratchet would have made dealing with a retaining bolt easier too.
A fair amount of time was spent trying to work out how to get to things so if I ever have to do it again (and I hope not) I suspect it'd be down to around 30 hours.
Anybody contemplating diy replacement:
1. you need to be stubborn. Very stubborn.
2. you need to be tall enough to be able to stand by the rh wheel arch and reach down behind the left hand side of the oil filter bracket with your left hand
3. you'll need relatively slim forearms and still be prepared to cut yourself to ribbons
4. you need to be able to spend a fair amount of time working by feel alone whilst trying to picture what you're doing
5. you need to be flexible in your approach and MacGyver some tools
6. you need to be stubborn. yes, I know this is point 1, but you really, really need to be stubborn
7. you have to have a plan in case the job goes tits up after you've got beyond the point of no return

What helped me was to repeat a mantra - "30 hours at Audi rates".

Two very useful tools - a magnetic pickup tool and a reel of strimmer cable. The pickup tool so you don't drop bolts you're removing and the cable to tie to tools in case you drop them into the engine compartment - and trust me, you WILL drop tools - luckily, the only one I dropped that wasn't tied fell all the way to the downpipe and I was able to reach it from below.

*it took over a week for the lacerations on my left arm and hand to heal. I suspect I'll carry the scars for the rest of my life.

Additional:
Was it the worst job I've ever done on a car? Probably not, but it's right up there near the top of the list.

Well done Jim for getting this done!

[Jim Haseltine]

The next 'big' job on the cards is the oil seal. I'm still in two minds as to whether I attempt it or not.
One curious thing I've found is that Lamborghini list the pump drive shaft seals at half the price that Audi charge - same part numbers, same dimensions.
Not that a fiver is going to make much difference......

[DJ Kill]

These pipes even officially replaced w/o engine removal. 8 hours according ELSA
Officially you need just unmount intake manifold.
Unofficially you can do it even with intake manifold on the engine.

I did this exercise in October with intake manifold removing cause I decide to clean the intake.

P. S. I don't know any coolant pipes that requires engine removal on RS6.
P. P. S. One garage in Nederland now familiar with that procedure.

[douglas96]

These pipes even officially replaced w/o engine removal. 8 hours according ELSA
Officially you need just unmount intake manifold.
Unofficially you can do it even with intake manifold on the engine.

I did this exercise in October with intake manifold removing cause I decide to clean the intake.

P. S. I don't know any coolant pipes that requires engine removal on RS6.
P. P. S. One garage in Nederland now familiar with that procedure.

Perhaps the routing is different on LHD cars compared to the RHD vehicles making it less/more difficult respectively?

[DJ Kill]

Perhaps the routing is different on LHD cars compared to the RHD vehicles making it less/more difficult respectively?

ELSA shows the same 8 hours for all cars.
All parts are the same. Steering column goes lower.
So, I don't expect many difference in procedure.

[Jim Haseltine]

These pipes even officially replaced w/o engine removal. 8 hours according ELSA

Took me 8 hours just to release the return pipe from the heater hose - breaking the seal from 8 years of a hot rubber/metal interface by feel and the fingers of one hand.

[timthetooth]

Chaps,
I have just had the coolant pipes in my 2008 C6 at my local garage in Epping Essex. It was not booked in for that (was having Service, MOT, and front suspension arms), the mechanic noticed some weeping from the drivers side wheel arch. When they phoned to tell me, they had already done the job (they have a mechanic with small hands who got the job!). You know the type of phone call, voice like somebody had died, but I was delighted, as the bill of £800-900 was a quarter of that quoted by MRC (they still prefer to remove the engine as of Sumer 2017).
I would thoroughly recommend the garage, they have dealt with various cars for me over the years, and one of the owners, Peter, used to own a C5 RS6. They use Audi parts, unless you have another preference, and are honest.
PMW is their name, usual disclaimers, I am just a customer.
Tim

[daviehannah]

Hi there, what garage was this please, have this problem now

[Doug_RS6]

Suggestion for people with only corrosion in the wheel arch area. I cut out the corroded section about 8 inches on each pipe. Using a small pipe cutter (needs to be small to be able to turn it) then pushed rubber hose on about 3 inches onto each pipe to get a tight fit as the pipe isnt flared. I then used a good quality clamp on each end. I also made some protective pads up and secured each hose together. I then liberally coated the metal sections with wax oil. Been good for 10 months so far and cost me around £8 for the hose and clamps. Wax oil I had in the house.