How to prevent rusty rear arches, sills

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Brett_Sinclair
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How to prevent rusty rear arches, sills

Post by Brett_Sinclair » Sat Dec 18, 2021 8:23 pm

Hi Bongonauts,

Sorry if this has been asked before but I'm struggling to find an answer

Many bongos fall foul of the dreaded rust on the rear arches and sills.

My question is: are these these areas susceptible to rust because of known design problems?
If so has anyone successfully found a solution so that these areas only rust as fast as the rest of the van :D

Thanks all
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g8dhe
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Re: How to prevent rusty rear arches, sills

Post by g8dhe » Sat Dec 18, 2021 10:13 pm

Well all vehicles are susceptible! Provided the underside of the vehicle and its cavities have been treated and undersealed then they should last a reasonable time, and if maintained with regular top up coats then they will last longer but its inevitable that eventually the arches and cills will finally succumb to rust along with the font and rear cross members. Remember these are 20+ year old vehicles which aren't treated during manufacture in Japan as they don't use salt on the rods which accelerates the process.
Geoff
2001 Aero V6, AFT, full side conversion.
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Northern Bongolow
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Re: How to prevent rusty rear arches, sills

Post by Northern Bongolow » Sun Dec 19, 2021 7:42 am

The sills don't usually rust unless damaged, providing the rear arches are good. The inner arch and outer arch start to come apart this let's water in which expands the spot welded seam further until rust gets going.as the wheel arch lets in water it collects down on the sill this then rusts through them and gets into to the sill full length. There are sill gromets to get a camera or waxoil sprayer in.
Moisture from a non insulated van also rots the arches from the inside, take off the inner rear panels and have a look, they are usually surface rusted.
Brett_Sinclair
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Re: How to prevent rusty rear arches, sills

Post by Brett_Sinclair » Sun Dec 19, 2021 1:44 pm

Thanks everyone, I have seen some people have fitted plastic covers to their arches. Do people do this to stop water getting in between the inner arch and outer arch? Or maybe do people just put them on so that don't have to watch while their arches rust away :D

Thanks for the help
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g8dhe
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Re: How to prevent rusty rear arches, sills

Post by g8dhe » Sun Dec 19, 2021 2:17 pm

To cover up the rust that is showing before they put the covers on!
Beware they trap the moisture and then fall of with the rust, which then means urgent fixing!
Geoff
2001 Aero V6, AFT, full side conversion.
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