Drooping nearside rear bumper ?

Technical questions and answers about the Mazda Bongo

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mikeonb4c
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Re: Drooping nearside rear bumper ?

Post by mikeonb4c » Thu Apr 05, 2012 9:42 pm

Hmm. Worrying news for towbar mounted backbox users? Nearly bought one but opted for a trailer in the end.
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Re: Drooping nearside rear bumper ?

Post by g8dhe » Thu Apr 05, 2012 10:24 pm

Ours has been fine since it was seam welded, including some strain put on it whilst pulling out of a wild camp one morning when the frame brushed against the ground crossing a bump, which wiped the nearside rear lights off, I keep a couple of spare bolts in the frame now for any future mishaps ;-)
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Re: Drooping nearside rear bumper ?

Post by Mark.T » Fri Sep 05, 2014 12:51 pm

A very useful thread, thanks. I guess this is also useful for people that use tow bar mounted bike racks. I've been considering a tow bar for this purpose, so if I proceed, I'll probably take it to a decent place to get it fitted, instead of mounting it myself!

Incidentally, would this be the reason that some manufacturers do not recommend the use of tow bar mounted bike racks?

eg: (FAQs at the bottom of the page): http://www.ebay.co.uk/itm/Mazda-Bongo-T ... 3f3bc43d29
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Re: Drooping nearside rear bumper ?

Post by g8dhe » Fri Sep 05, 2014 3:45 pm

The Thule box we use has a lot of stickers indicating that the Max load is 50Kg, which is effectively the nose weight that most vehicles and towbars are designed to withstand. However after all is said and done it still depends on the mounting of them to the vehicle if that is not up to the job then .....
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Re: Drooping nearside rear bumper ?

Post by Doone » Fri Sep 05, 2014 4:50 pm

I've been considering a tow bar for this purpose, so if I proceed, I'll probably take it to a decent place to get it fitted, instead of mounting it myself!
My advice is to take it to one who can weld, they'll make the Bongo strong enough for the job. :)

And fit a really good quality tow bar too!
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Re: Drooping nearside rear bumper ?

Post by Simon Jones » Fri Sep 05, 2014 6:32 pm

I'd get a better quaility towbar such as A1's MA465 model which is properly made. If towbars were not suitable for mounting bike racks etc, then why do car manufacturers sell such racks as accessories with the factory fitted towbars? 75kg is the standard towbar nose weight for the Bongo as far as I know.
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Re: Drooping nearside rear bumper ?

Post by g8dhe » Fri Sep 05, 2014 10:26 pm

Yes the box takes 50Kg, but with its own weight and the mounting rack that gets it close to the 75Kg, plus of course there is some rotating torque on the assembly rather than a direct vertical force.
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Re: Drooping nearside rear bumper ?

Post by Mark.T » Fri Sep 05, 2014 10:42 pm

I'm not sure, but I guess there is more of a twisting moment with a full box or cycle carrier than there would be with a trailer? The experiences above show that Mazda may not have designed the mounts for these kinds of stresses, but predominately vertical stress are obviously OK :)

A place that can weld: Certainly, by the sounds of it! :)

Food for thought, thanks :)

Edit: Rats, wife distracted me and got beaten to the above point :roll:

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Re: Drooping nearside rear bumper ?

Post by g8dhe » Sun Oct 11, 2015 10:25 pm

Further to the saga and copied from other discussions about towbars since I thought I'd add this as the final point about towbars!

However whilst ordering another TowTrust replacment, I checked the two designs and in the future I will be changing it for the A1 Towing design much more rugged, and they seem to know about the near side weld problem!
Here are both manuals, as you can see the nearside construction is much more robust, even if more difficult to fit! The off side mounting on the TwoTrust design bends at the single bolt on the under surface, the other design eliminates this problem by not having an underside to bend! The bar is bolted directly to the end plate which is much stronger!
http://www.g8dhe.net/bongo_images/A1_To ... 65_A-3.pdf
http://www.g8dhe.net/bongo_images/Tow_Trust_TMZ168.pdf
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Re: Drooping nearside rear bumper ?

Post by mikeWalsall » Mon Oct 12, 2015 9:49 am

I have the A1 MA 465 fitted on my V6 .. only towed an 'up the tip' trailer ..never towed a Caravan..

But last week I removed a very over grown row of bushes from the bottom of my garden with a chain around the tow ball ..

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I initially used a brand new polypropylene four ton tow 'rope' which soon broke ..

Not a even a groan from the tow bar or the Bongo .. if the roots where still in to deep the Bongo just stayed to the limit of the chains ..

Not a complaint from the engine .. temp: stayed as normal..

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Re: Drooping nearside rear bumper ?

Post by Gasy » Sat Aug 20, 2016 9:11 am

When mine went my cheaper tow bar was twisted
The big square bar that is vis able from the back was twisted by 30 degrees downwards
and it split a bolt hole
My tow ball was visibly at the wrong angle that much my misses said that seems to be downwards abit
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Re: Drooping nearside rear bumper ?

Post by willow2u » Thu Sep 10, 2020 11:18 pm

The near side rear bracket that most towbars bolt to is not fit for purpose it’s a lightweight bracket purely to bolt the bumper to even seam welding it would only make it barely adequate imo