robt964

Well, what started as a simple task has just got a whole lot more complicated.

I bought my C2 in December 2012 and the oil level gauge has never work. So the new one arrived in the post and I thought I quickly swap them over this morning.

That was the plan...

The sender was so heavily corroded, that with all dome nuts removed it wouldn't shift. It was completely stuck fast :-(
I spent ages chipping away at the base of the 6 studs trying to free it. In the end I had to start levering the sender which I was very cautious of doing. I had to lever it as hard as I dared before it started to move, but only the corner being levered. The others wouldn't move together. In the end it took me nearly 2 hours to get the frickin thing off and had to destroy it in doing so.




This distructive measure caused a few other issues. I couldn't be certain that parts and/or rust chunks from the sender hadn't fallen into the tank during its extraction. I spent another 30mins checking the condition of the various hoses and the tank itself. Some of the hoses were perishing, the metal oil pipe that runs on the inside of the wheel was bubbling heavily from corrosion and the tank itself wasn't looking that great. I came to the decision to pull the tank and all the connecting hoses

Getting it out wasn't straight forward either. The nuts on the rubber mounting bobbins were completely rusted and stuck which meant I had to cut them off.
The clamps on all the hoses that connect to the top of the tank were corroded and rounded. I couldn't shift or cut them from within the arch so had to disconnect the other end of the hoses from the engine bay and pull them through in the arch. Finally the tank was free, but not very pretty.





The short stubby hoses were all in good condition but the two top large hoses are going to need replacement. Certainly not wanting to fork out for a new tank (no idea what they cost but I bet its ALOT) I spend 2 hours cleaning it up with a drill mounted flap wheel and a bit of hand finishing. After removing all the loose paint and rust, thankfully the tank is still in useable condition and not nearly as bad as it first looked. Phew!






I'll give it a really good rinse, degrease and treat the tiny rust spots during the week before repainting.

Question 1) What should I paint it with?
As this gets relatively hot I'll have to choose the paint with that in mind. I'm thinking Satin black HT engine enamel, or maybe POR 15 ? Should I primer it with something? I want this to last a loooong time as don't want to repeat this anytime soon!

Once the the tank was out it was obvious that the top mounting bracket that's spot welded to the inner wing was also suffering. Sections around its base have rotted all the way through.



Anybody seen this before? What's the remedy? By the look of things the bracket will have to be cut out, the rot behind cut out and a patch welded over the hole?

Question 2) Anybody else suffered from this? What was your approach to a fix?

Thanks Rob

sml

wow ... how much is a new one? you're investing a lot of time there.

ThomasC2

You UK guys really have corrosion in ways you don't see very often!

But a nice save of the tank. I haven't looked it up in PET but I think a new one is a lot of ££££!

Thomas

Vandit

DCAuto says $300USD. Not bad at all. I'm surprised.

HiWind

Nice clean up and you found some worm before it got worse.
Sorry cant comment on paint but your ideas sound right.
Good luck!

Ps - tanks is $1670 per autoatlanta ... So worth the 1-2 hrs and a polishing bit
PPS - DC Auto! Nice repository of used parts!

boxsey911

Hi Rob, I can now confirm that there is indeed a rust spot on the interior side of my arch in that position, just as you spotted! No doubt it will be worse on the outside, just as yours is. At the moment I'll just have to put it down as a job for the future but clean it up on the inside and treat it POR15 or similar. Thanks for the heads up. I think!

robt964

LOL - you're welcome :-)

Yes unfortunately the rot is a little worse on the other side. I recon I need to cut out a section about 5x4 cm. It's a job I'll do one eve this week before butt welding in a new piece at the weekend.

The good news is I picked up all the new tank hoses and pipes from my OPC today so hopefully this "small job" won't keep me too long from the other jobs I've got coming :-)

HiWind

What is the source of the corrosion in UK? Never being more than 70 miles from the Sea?
Air quality? Just the rain?

robt964

The UKs position on the globe is right under the north atlantic golf stream so it gets plenty of rain!! Mix that with salted roads in winter and it can easily be 2 or 3 months of dampness at a time that means the vehicle just doesn't get to dry out!

ZG862

Salt on the roads in the winter. Usually applied a couple of weeks before ice and not at all when ice is actually forming. This is because weather catches us by surprise. Again. And again.

robt964

This evening I cut out the rust hole back to clean metal and shaped a section and new mounting bracket to weld in.

From the inside...


and view from within the arch...


Having never performed bodywork on a Porsche before, I do have a few questions.

For ease of access, I'll weld the new infill piece from inside the car. Now I understand these cars are galvanized but is that just the detachable body panels (bonnet/hood, doors, wings etc) or does that include the main tub also? If so, is it just the outside or the inside also?
I've not welded a galvanized car before so any advice would be extremely welcome!

Also, from the view within the arch photo you can see that under the red paint the metal has first been been coated/sprayed with a thick layer of a yellow-ish paint that has a small degree of elasticity. Anybody know where I can get this or a suitable alternative I should use? I'd like to ensure that on completion of this work I haven't compromised the weather proofing of the car.

Thanks

Rob

Metal Guru

Add in the fact that it seems that very few people in the UK ever seem to put their cars away when it's wet.

FeralComprehension

Wear a real respirator: Metal Fume Fever

robt964

How thick is the galvanization? Do I need to grind that off the weld area first?
To be honest, after the flapper wheel had cleaned up the area to bare metal the finish looks just like regular steel !

Re Metal Fever - thankfully I only have a very small section to weld that should take no more 2-3 minutes of short stitches :-)

pi5tolpete

Bringing this thread back.

My tank is loose and moving nicely towards the rear. I'm wondering what to do with the level sender and the dipstick tube. The coupling for the dipstick tube feels very tight and I'd prefer to de-couple with the tank out and braced so that I don't round off the nut. Can the dipstick tube come out the hole and get through even with the flare at the end? And what do I do with the sender wire? Do I unplug in the engine bay and thread the plug through towards the tank? The wire seems captured at the tank with a rolled sheet of metal.

Thoughts?