W124 Fuel tank Breather pipe

[BlueQuinn]

My 300TE passed it's MoT today, which I'm very pleased about, but while it was on the ramp the tester showed me that the hard breather line from the fuel tank to the filler was very rusty.

(Annoyingly this was an advisory on the old MoT and the vendor told me he had sorted it.)

The thing is, the parts diagrams seem to show a hose here, not a hard line.
Or am I looking at the wrong bit?

 

[hotrodder]

The filler vent is indeed a rubber hose, open the boot side compartment and it's visible along with it's connection to the filler neck. It's plumbed into the top right hand side of the tank and only really a breather when filling the tank unless pressure in the tank rises high enough to open the pressure relief valve in the filler cap

There's another (active) vent to deal with evaporative emissions and pressure/vacuum due to temp changes/using fuel. This is a smaller dia hard line, obviously with rubber hose connections for movement/vibration etc. Enters the tank vertically from below about half way up the front right hand side via a plastic check valve and is routed to the front of the car. Outlet and fuel return are plumbed into the tank roughly front centre, again about half way up

All the hardlines (brake/fuel/SLS) are prone to corrosion if they haven't already been replaced/treated regularly and on estates the bottom of the filler neck itself (where it joins the tank) is right in the firing line of crud thrown up by the OSR wheel and a commonish rust spot

 

[stability]

excellent advise hotrodder -you know this well

 

[balge]

There is a short metal section at both ends of the vent tube, could be one of those? Or the filler neck itself (quite probable) as mentioned

 

[BlueQuinn]

I'm going to have to crawl under there with a camera. Why did I not take a photo when it was on the ramp

Also, there's a leak from the front of the exhaust-side of the camshaft cover (m104 engine). I'm hoping it just needs torqueing up properly (10Nm I think?) but could it be anything else?

 

[BlueQuinn]

I took some photos of the pipe in question.
Which pipe is this, and do you think it needs replacing or can I get away with a wire brush and some anti-rust paint?

All sizes | Fuel pipe rust | Flickr - Photo Sharing!

All sizes | Fuel pipe rust 2 | Flickr - Photo Sharing!

 

[balge]

SLS feed to top of hydraulic ram?

No sign of oil leaks...

I would give it some with a wire brush to check before rust-proofing

 

[Dieselman]

That is an SLS pipe. Give it a rub down and see what it's like, then treat it if not too bad.

 

[BlueQuinn]

Brilliant! I am so relieved it's not a fuel pipe.

 

[balge]

Not necessarily, some of those SLS pipes are a ridiculous price if they do need replacing...

 

[BlueQuinn]

At least it's not going to catch fire. If it is beyond redemption, and replacements are too much, can you get them made by a brake pipe place?

 

[balge]

Good point!
Not sure about getting the lines made up, would have thought a hydraulic fitting place would be a better bet, might be worth an ask if one of the pricier ones are required...It's not like they're hundreds of Pounds, just seem to recall thinking they were a bit eye-watering for bits of bent piping...