Leaking Roof

[Paul Mc]

Leaking Roof.
I’m trying to find a suitable sealant or mastic to fill up some gaps around the base/rim of the pop-up roof.
Has anyone had to do this yet?
Thanks

 

[BabaJen]

How old is your vehicle? Surely it's a warranty job?

 

[Paul Mc]

Only 6 months old and it’s been back to the dealership’s workshop for 3 days.
This is the best they could do and it’s still leaking despite having been put through a water test/check by the MB technicians!

 

[BabaJen]

I feel for you. That is unacceptable. A new vehicle. It should be fixed under warranty, fixed properly, whatever the cost, no questions.

 

[JulieG]

We had a similar issue with our roof which was successfully sorted by our local MB dealer in Harrogate, the work done under warranty.
They apparently replaced a faulty gasket at the base of the pop up bellows.

 

[Paul Mc]

We had a similar issue with our roof which was successfully sorted by our local MB dealer in Harrogate, the work done under warranty.
They apparently replaced a faulty gasket at the base of the pop up bellows.

Would be interesting to see how they sealed round the cables at the back of the your roof base. Thanks

 

[JulieG]

Would be interesting to see how they sealed round the cables at the back of the your roof base. Thanks

Hi Paul
Photo as requested

 

[Epigram]

I have just looked at the cable seals on my new MP which are identical to the pictures posted by JulieG.

The gasket/seal on the inside (presumably) should prevent water ingress on its own.

Putting silicon sealant on the outside around the cable entries is masking the problem and not addressing it at source.

I would be most unhappy with a repair to prevent water coming in that is not to the manufacturer’s original design, especially in a new vehicle.

Paul, my advice, for what it’s worth, take it back and insist on a repair that is fit for purpose and will last the life of the vehicle.

Good luck and keep us posted.

 

[Paul Mc]

Thanks, Epigram - that’s a valid argument.
Could you take a few photos of the rear section of your roof for me.
I’ll need as much evidence as I can gather.

 

[Ragga]

Hello Paul. I installed a solar panel last year & chose to run the cable from the panel through the same hole as the cable to the elevating roof piston.
I researched the sealant used in the original manufacture. It was Sikalastomer 710 rubber based butyl sealant. Available in different colours. I bought grey & it is perfect colour match to the original sealant.
When applying the sealant,
- I used a fine nozzle,
- ensured that a bead of sealant was all around the cable as it entered the van from the outside
- checked the sealant had penetrated into the van. To do this I removed the plastic cover plate (pictures 5 & 6 in your original post).
- Note that the sealant is very “stringy” so cover up anything you don’t want the sealant to adhere to.
I did this work last August & have slept in the roof when it has been raining hard outside. To date no issues.

 

[Paul Mc]

Hi Paul
Photo as requested

View attachment 446View attachment 447

Thank you, Julie.
Did you receive any documentation from the dealership service department confirming that the seals or gaskets were actually replaced? I didn’t get any paperwork stating what work was carried out, so I’m presuming (as highlighted by Epigram) that the work done is just masking the problem and not addressing it at source.

 

[Epigram]

Hi Paul
Photos a requested. Roof not been up in the rain yet.

 

[Paul Mc]

Hello Paul. I installed a solar panel last year & chose to run the cable from the panel through the same hole as the cable to the elevating roof piston.
I researched the sealant used in the original manufacture. It was Sikalastomer 710 rubber based butyl sealant. Available in different colours. I bought grey & it is perfect colour match to the original sealant.
When applying the sealant,
- I used a fine nozzle,
- ensured that a bead of sealant was all around the cable as it entered the van from the outside
- checked the sealant had penetrated into the van. To do this I removed the plastic cover plate (pictures 5 & 6 in your original post).
- Note that the sealant is very “stringy” so cover up anything you don’t want the sealant to adhere to.
I did this work last August & have slept in the roof when it has been raining hard outside. To date no issues.

Hello Paul. I installed a solar panel last year & chose to run the cable from the panel through the same hole as the cable to the elevating roof piston.
I researched the sealant used in the original manufacture. It was Sikalastomer 710 rubber based butyl sealant. Available in different colours. I bought grey & it is perfect colour match to the original sealant.
When applying the sealant,
- I used a fine nozzle,
- ensured that a bead of sealant was all around the cable as it entered the van from the outside
- checked the sealant had penetrated into the van. To do this I removed the plastic cover plate (pictures 5 & 6 in your original post).
- Note that the sealant is very “stringy” so cover up anything you don’t want the sealant to adhere to.
I did this work last August & have slept in the roof when it has been raining hard outside. To date no issues.

Hi Ragga
Are you saying that the original seal/gasket or grummet for the cable is in fact squirt of rubber based butyl sealant?
How would the 710 rubber based sealant compare to the Sikaflex-221 Polyurethane Sealant?
Could the 710 sealant be used to fill gaps in the original gray sealant under the aluminium rim (see photo)?
Thanks

 

[Paul Mc]

Hi Paul
Photos a requested. Roof not been up in the rain yet.

Thanks, Epigram

 

[Ragga]

As I recall, the cable for the piston runs inside a flexible plastic sheath. As the sheath enters through the rear of the van it does so through a black foam seal sandwich (as per your original photo).
To the left & right of this entry point you can see the grey sikalastomer. When I added the solar cable, I opened up the black foam sandwich to accept the additional cable, then sealed around both the new cable & existing sheath.
710 is the product Sika suggest using for this task as it retains its flexibility (https://gbr.sika.com/dms/getdocumen...b2-fe094fabde95/SikaLastomer_710_e_v10_03.pdf). I don’t know about 221.
I tackled a small area and got a good seal using this product. It was my choice to extend the penetration for an extra cable and I accept that should I get a leak in that area of the van it will be my problem to solve. If I thought I had a large leak, not of my own making, I would be revisiting the MB dealer and talking through the remediation options with them first.

 

[JulieG]

Thank you, Julie.
Did you receive any documentation from the dealership service department confirming that the seals or gaskets were actually replaced? I didn’t get any paperwork stating what work was carried out, so I’m presuming (as highlighted by Epigram) that the work done is just masking the problem and not addressing it at source.

Stupidly we did not ask for any documentation.

 

[Epigram]

Paul Mc For info.
With some trepidation I gave the cable entries a good spray with the garden hose today to confirm that there are no leaks. It is a representative check because this would be the side that would typically be most exposed if the vehicle were parked with the roof up and the rear facing the wind against in driving rain. I would sooner know if there were a leak when I am not sleeping in the vehicle.
Therefore, as Raga says the black foam sandwich around the cable entry is sufficient to stop leaks on its own without the need additional sealant.
Raga: Interesting research re cable entry for solar panel and sealing the additional cable.

 

[Ragga]

For the record, there is a German website that describes the construction roof detail for the previous generation Marco Polo. I attach two links below.

Mercedes-Benz Teilekatalog (Ersatzteile online)

mb-teilekatalog.info

Mercedes-Benz Teilekatalog (Ersatzteile online)

mb-teilekatalog.info

There is not that much difference between the two generations.

 

[Yodaegghoover]

We had a similar issue with our roof which was successfully sorted by our local MB dealer in Harrogate, the work done under warranty.
They apparently replaced a faulty gasket at the base of the pop up bellows.

Hi, did the faulty gasket result in water coming in above the head lining. I have water entering mine just above the sliding window above the fridge. Cannot see anything obvious with the roof up, but it is definitely letting in a lot of water.

 

[SteveB]

As far as I can recall it was at the base of the bellows resultino in water dripping down the front of the wardrobe.