Rust treatment Whats the best.

[Bongolia]

Bongolia, I think in your case the only way to eliminate the rust is to Jack up the Wing/door Mirrors and replace the van.
Making sure that the Mirrors are not tRusted.


Good Luck.

Checked the mirrors this morning....
Thats a no go Rita

[Bongolia]

Waxoyl only regularly needs redoing in high abrasion / water washed areas?

Not a folly Bongolia, just the selfless devotion of someone determined to restore an old classic. You'll love it once its done

I love a challenge
I have just given rear X member a good prod and now most of it is on the floor!!
Just keeps getting better!!

[Bongolia]

Hi
Bongolia
I used to buy lead scrap by the hundredweight and alloy it / clean it in a small furnace ...MUCH cheaper!!!
I remember that underseal / rust treatment...The name eludes me for the moment...it was thought to be the real deal, and everyone used it / sold it on new cars in the early '70's....It was really tough, and stopped any attack from salt / water etc. The only problem was that it rusted underneath and you couldn't see!!!!...LOL
Mike...
Waxoyl needs topping up in most places, and I don't use it at all on rain / water-washed areas!
Cheers
Helen

If I remember it was made by Dunlop and called Road Seal or something like that.
Bitumen based stuff. Used to go brittle once it had aged and in the cold weather would crack around the panel seams causing horrendous rusting at the worst possible place.
The only way to get it off was scraping and air chisel. Couldn't warm it as it became liquid!
My Humber had been "treated" with it, I was under that thing for best part of three days getting it off!

[helen&tony]

Hi
Bongolia...
No...that wasn't the name...it was a trade only application, and absolutely every dealership thought it was the best thing since sliced bread...but after some years, it proved rubbish...I can't remember the name....flippin' expensive too!
What can work pretty well is asphaltic bitumen....it stays flexible, and seems self healing...but it has to be melted and applied hot!....I tend to use Waxoyls underseal mostly
Cheers
Helen

[Bongolia]

Now I am curious, like when you cannot remember someones name.
Ziebart?

[helen&tony]

Hi
Zeibart...that's the one...It turned out to be absolute rubbish, and a lot of dealers genuinely thought they were selling a good product!...I worked in the offices of a couple of main dealers, and the Zeibart was a pretty pricey deal....I seem to remember that it failed spectacularly, and "treated" vehicles were found to have rusted UNDERNEATH the coating without owners noticing!
Cheers
Helen

[mikeonb4c]

I've come think there is an immutable truth: the softer the treatment the less prone it will be to drying out, cracking, delaminating (due to differential expansion) and allowing water to get behind and allow concealed rustaway. But it will also be more prone to washing off due to road spray etc. I guess the advice should be to use softer waxoyl for internal injection and for external areas not exposed to spray. For other areas use harder type waxes like dinitrol but inspect annually and renew around every 3 years (as i was advised to but neglected to do on one occasion and paid the price). In practice this probably means wheel arches, cills and cross members. Soft waxoyl is in any case horrible stuff to have around areas where you might want to do spannerwork (though arguably may help stop nuts seizing with rust). All waxoyl is not welcomed by welders!

I've sometimes wondered if open drain holes with venturi inducing cowls might be worth fitting on to Bongo cills.

[mikeonb4c]

Waxoyl only regularly needs redoing in high abrasion / water washed areas?

Not a folly Bongolia, just the selfless devotion of someone determined to restore an old classic. You'll love it once its done

I love a challenge
I have just given rear X member a good prod and now most of it is on the floor!!
Just keeps getting better!!

If its any consolation, I had to have mine welded up, in the area behind the rear silencer heatshield. It was a complex job the welder said but he did a beautiful job and hopefully we won't be visiting there again for many years. I think my problem may have been caused in part by an inner arch rust-through and/or a compromised bumper assembly resulting from catching the bumper once when reversing. The consequence was that road spray was get through to a place it shouldn't. That, combined with warmth courtesy of the rear silencer might have created optimum rusting conditions. I've just had welding done to n/s/r inner arch and new bumper mounting and new bumper sprayed and fitted. Cill end was done at the same time. Bit by bit she's becoming a thoroughly sorted Bongo, though i know i must expect the bills to continue one way or another.

I do wonder, looking at all the owners on facebook with proudly resprayed Bongos, how many may have rust lurking in well hidden locations. Personally, i think a lot of what you're discovering is best discovered and dealt with as the end result should be a fundamentally sound structure for years to come. Its a true restoration project! The rust that bothers me more on Bongos is the upper body stuff, where welding may be trickier to do without damaging interior etc. I'll be interested to follow how Geoff gets on sorting his and i hope he'll keep us posted. I think cold techniques are worth serious consideration in these areas, and they've worked quite well for me on wheel arches and bottom strip of tailgate.

[Bongolia]

Waxoyl only regularly needs redoing in high abrasion / water washed areas?

Not a folly Bongolia, just the selfless devotion of someone determined to restore an old classic. You'll love it once its done

I love a challenge
I have just given rear X member a good prod and now most of it is on the floor!!
Just keeps getting better!!

If its any consolation, I had to have mine welded up, in the area behind the rear silencer heatshield. It was a complex job the welder said but he did a beautiful job and hopefully we won't be visiting there again for many years. I think my problem may have been caused in part by an inner arch rust-through and/or a compromised bumper assembly resulting from catching the bumper once when reversing. The consequence was that road spray was get through to a place it shouldn't. That, combined with warmth courtesy of the rear silencer might have created optimum rusting conditions. I've just had welding done to n/s/r inner arch and new bumper mounting and new bumper sprayed and fitted. Cill end was done at the same time. Bit by bit she's becoming a thoroughly sorted Bongo, though i know i must expect the bills to continue one way or another.

I do wonder, looking at all the owners on facebook with proudly resprayed Bongos, how many may have rust lurking in well hidden locations. Personally, i think a lot of what you're discovering is best discovered and dealt with as the end result should be a fundamentally sound structure for years to come. Its a true restoration project! The rust that bothers me more on Bongos is the upper body stuff, where welding may be trickier to do without damaging interior etc. I'll be interested to follow how Geoff gets on sorting his and i hope he'll keep us posted. I think cold techniques are worth serious consideration in these areas, and they've worked quite well for me on wheel arches and bottom strip of tailgate.

Yes I think your right and combine that with the vent outlet box behind the bumper at that point being of thin gauge metal susceptible to early failure do to its position and poor coating protection.


A good number I would imagine.

I have a similar problem to Geoff although not as advanced, I was going to cold repair the area but instead have decided to remake it but only because I will weld in mounting points for a wind out awning and the interior is stripped out. But if the sub structure is good I can see no reason not to cold repair although it is the owners personal preference.
Another area that has come on in leaps and bounds over the past few year is the use of structrual body adhesives. Taking Geoffs as an example and again if the inner is sound, cap could be cut from a donor vehicle and quite literally stuck on.

I wonder if an investment might be made in a cheap endoscope as part of the owners tool kit. They are available on Fleebay. I use one linked to my mobile phone via an OTR adaptor and an Android free app from Playstore.

As to the construction of the sills and box sections, when I removed the inner sill section to access the lower portion of the A pillar I was surprised to find that the A pillar box stops short of connecting to the rear inner box section,it would seem that the designers felt this would be adequate and may form part of the crumple zone.
However a few years down the line...
I would say that this section of the van is critical in any impact to the lower A pillar slowing intrusion into the footwell.
The thickness of steel of the outer sill cover is just 22swg. Corrosion around this area could have serious consequences and is well hidden beneath the outer..
As mine had had a butt welded sill section "let in" as a result of previous accident damage to that area, we decided to reinforce the sill outer from the inside and connect the two boxes by boxing with 18 swg material ,the factory internal boxes are 18 swg, although the NS is not as badly affected by corrosion we will be removing the inner sill at that point and inserting a connecting box there also.
So these things are/would be visible with an endoscope.
It is interesting dissecting the Bongo and looking at its construction. I think there is nothing inherently wrong with the construction method or techniques used by Mazda it seems to be that the problem is just,as is pretty well known, the lack of rust prevention at the factory.

[Bongolia]

Mike , off topic, but some time ago you where in a discussion with a poster about installing a Webasto Thermo Top.
There was some talk of Factsheet being produced , did that ever happen? I can find nothing in the members area.

[mikeonb4c]

Mike , off topic, but some time ago you where in a discussion with a poster about installing a Webasto Thermo Top.
There was some talk of Factsheet being produced , did that ever happen? I can find nothing in the members area.

I've not looked but i suspect not. Geniuses pop up on here only to disappear quickly, taking their wisdom with them. Its a shame

I love the idea of an engine calorifier and a webasto being used to produce hot water and radiant heating rather than less healthy and more noisy blown air heating. The Bongos coolant circuit and heater rads could help distribute the warmth and the warmed engine and gearbox could offset some of the diesel used through more efficient running from start-up.

[Bongolia]

Thanks, looks like I am going to bite the bullet and fit one instead of the Propex. There is probably enough info in the posts to do it. Would have been easier to follow in others footsteps.
Agree on the heated air quality and there would be significant reduction in noise compared to a Propex not to mention the engine warm up and I quite like the idea of using the existing distribution system
Synergy.

[g8dhe]

Only problem with the existing distribution system is that the fans are not very power efficient They take between around 10 Amps each, fine when your relying on the alternator but a bit excessive if your relying on LB!!!

[mikeonb4c]

Thanks, looks like I am going to bite the bullet and fit one instead of the Propex. There is probably enough info in the posts to do it. Would have been easier to follow in others footsteps.
Agree on the heated air quality and there would be significant reduction in noise compared to a Propex not to mention the engine warm up and I quite like the idea of using the existing distribution system
Synergy.

The restoration project just got a whole lot more interesting. Will be v interested to follow this one. With the large thermal mass of the bongo engine to store heat in you would hope there might be decent intervals between propex burner having to switch on, if you can set min and max on the propex thermostat a couple of degrees apart.

[g8dhe]

Here is an idea http://www.4crawler.com/4x4/CheapTricks/Shower.shtml
also here https://www.youtube.com/watch?v=Kn_VTsiMsZU
and some other ideas https://encrypted.google.com/search?q=v ... utf-8&aq=t