Rust

[Kelp]

I first noticed the paint lifting off from a screw hole on the water inlet. It doesn't have any sealer or gasket. The electrical inlet has a gasket but was far worse. It must have held the water in. After I scraped, sanded, primed and painted, I used foam tape to seal the water inlet. The battery vent had a better seal and was not as bad. They are all secured with stainless screws.
I agree. A little prevention would have gone a long way.

[LenS]

Mercedes-Benz Sprinter – production at the Düsseldorf factory: Precision to a fraction of a millimetre - quality workmanship at the main van factory - Daimler Global Media Site

"Paintwork: emu feathers and ultra-fine coats of paint
Ten pretreatment stations and an extremely complex painting process provide the body of every van from Düsseldorf with perfect protection against corrosion. The pretreatment process is preceded by a so-called bodywasher: at this station the entire body is cleaned on the outside by rotating spray wheels and on the inside by other spraying equipment.
The actual painting process comprises zinc phosphating, cathodic dip priming, filler coat and top coat. All the coats are ultra-fine, with a total thickness of 80 thousandths of a millimetre. On average, the paintwork on every Sprinter weighs in at 17.4 kg, and the painted surface area totals around 95 square metres.
Prior to top-coating, each body is cleaned with emu feathers on rotating rollers to remove the finest dust. Robots and employees share the task of sealing the body seams averaging a total length of 138 m with PVC. The water-based top coat is applied on four lines. Several hundred different colours are possible. The top coat is applied using electrostatic systems – the fine paint particles are attracted to the body by electrostatic means.
Cavity sealing involves the same high degree of precision as the painting process: a large number of nozzles specified for each individual model automatically spray a precisely defined quantity of the protective coating into every cavity on the body. Together with the galvanised body panels, the sum total of all corrosion prevention measures provides permanent protection in all areas at risk of corrosion – rust has no chance."

Even cut to bare steel and close to the ocean salt mist cathodic ELPO should have preformed better then what you show.

[86Scotty]

I know I'm largely preachin' to the choir here but SMB's work is riddled with ugly stuff like this under the edges. Sprinters are known to rust more too, not sure why but they do.

If you have an SMB and live in rust country I would take a look under everything, and often.

[LenS]

Interesting. Cathodic ELPO primer over CLEAN steel should not look like that for at least 8-10 years. Surprising, that would indicate that the steel being used is not cleanable by the assembly plant pre-cleaning operations in Germany. GM and Ford both spec. out the body steel as to what drawing oils and anti corrosion shipping oils can be used in the supplier steel plants. That is to assure that the steel can be CLEANED prior to the zinc phosphate treatment. Hopefully the Sprinter plant now up and running in the US has the proper processing.

[rallypanam]

Originally Posted by LenS

Interesting. Cathodic ELPO primer over CLEAN steel should not look like that for at least 8-10 years. Surprising, that would indicate that the steel being used is not cleanable by the assembly plant pre-cleaning operations in Germany. GM and Ford both spec. out the body steel as to what drawing oils and anti corrosion shipping oils can be used in the supplier steel plants. That is to assure that the steel can be CLEANED prior to the zinc phosphate treatment. Hopefully the Sprinter plant now up and running in the US has the proper processing.

It's been known for years that the Sprinter paint is crap..a friend if mine has painted his several times, and continues to chase rust. In California.

Then of course, SMB cutting holes and not treating them doesn't help any!

[arctictraveller]

[QUOTE=rallypanam;199114]It's been known for years that the Sprinter paint is crapQUOTE]


But, they use Emu feathers to prep with. That's high class.

[EmMay]

My Best Guess, Those Emu's dusting with their feathers must of worked on Kelp's Rig on a Friday...?

[TexomaPowerboater]

Could be related to electrolysis.

[BVerhulst]

Originally Posted by rallypanam

Then of course, SMB cutting holes and not treating them doesn't help any!

I think I'll be inspecting the holes cut in the body of my van soon...

[Fitz]

I pulled the cover off the electrical connection today and here is what I found:



As you can see, no treatment on the cut edges.

FYI, this is a 2016 Sprinter picked up new from SMB Austin in September of 2016.

In my case I am lucky, the gasket on the cover was doing its job and thus the edges have been somewhat protected.

Next will be to treat the cut edges at all locations. Color match isn't important as all locations are covered, any suggestions as to the best product to use to address this condition?