16" trailing arms removal and refurb

[jes*b]

Yep same issues here - I bought a job specific gedore 12mm extra long 1/2" drive hex bit to cover the distance. Wasn't cheap but as you say a lesser make might have twisted/ snapped etc or damaged the hex head.

[hotpod]

i broke the end of my improvised one off in the socket of one of the bolts so then discovered that a pipe wrench with a 1m scaff bar extension did the job beautifully.
on the other trailing arm i tried out the pipe wrench method on another two bolts to see if i could remove the hub before removing the backing plate. it worked fine with the bonus of removing all of the rust. i didnt complete the job though as i needed the leverage of the whole arm to get backing plate bolts off.
i have now cut the 16" extensions off the original arms, cut the ends off the donor arms, cut out the 16" spring plate reinforcements and removed the ones from the donor arms and sent everything off for shotblasting before assembly.
i have been taking some movies and photos for future reference.

[jes*b]

Good work. Post up something visual ??

[hotpod]

right, some pics:

the 16" SDP extensions showing the overlap. they were welded inside and out. next to the end of a standard trailing arm which was cut off the donor arm in the right place (the end of the flat top and bottom sections)



the plate which the hub bolts onto. the front edge (rhs in the pic) attaches at the same point which means that the hub mounting holes are 20mm further back.



this rather blurry pic shows an easy way to spot a 16" arm with them on the truck. there is no middle seam at the back and it is a different shape ( plus the hole is 20mm larger which you cant see in this image) it also shows the height difference of the shock mounts. these are actually the right way up, i.e. lower on the 16.



which brings me to a question before i weld them all together;
if i want to jack the van up more ( it already has seikel springs but i will be putting spacers on when it goes back together) does it make sense to swap the extensions round so that the shock mount point it at the top rather than the bottom?
they will be 30mm higher aprox if i do. is it a good idea or is there a good reason to leave it as is?




this image is of the reinforcing section which goes under the spring mounting plate on the 16. is is quite different to the standard ones although i have to say that the standard ones go all the way to the back and actually look a bit stronger.



and their position inside



one of the the pigtail recess's which i cut off the bottom side of the old arms and which i shall be using to make the new spring seating plates..no broken pigtails for me!




and on of the arms (donor standard arm and 16" extension) ready to start welding back together

[..lee..]

cracking work, been meaning to tackle this job myself for the doka project. have you looked in to lengthening the arms by more or less than the 16" arm. reason i`m asking is lengthening the arms reduces the clearance at the rear wheel arch.

cheers lee

[hotpod]

my idea for making the new spring seats turned out to be a good one. I cut out the pigtail recesses from the bottom sides of the scrapped arms before i binned them. Thew werent even rusty, the drain holes had done their job well. They went for shotblasting with the other parts, and when i got them back, i cut out spring seat sized circles from 3mm plate, and cut a hole in the middle of them to take the pigtail recess disks. i welded them together and ground the weld back. i then added 30mm of a 3mm walled tube of the right size ( this happened to be the shell of an old shock absorber) and found a good thick washer of the right size to cap the top. i then drilled 10mm holes around the plate for plug welding them to the arms.
when they come back from finishing * they will look like now i hope.

* i have to decide before monday 8am whether or not i will go for full hot dip galvanising, or hot zink spray and paint with a liberal internal wax oiling?
any thoughts on this will be appreciated.

the pros of hot dip are an excellent long term protection inside and out.
the cons are the added thickness inside the tubes for the rubber bushes ( could be an issue) and filling the tapped holes for the hub assembly, plus, that face is originally machined as far as i can make out and would therefore have to be machined again before i can use them.

the pros of hot zinc spray and paint are they will still be better than the original treatment, i wont need to re tap the holes or machine the face.
the cons are that they will never be fully treated with zinc inside. they can probably get to the bottom of the short arm but certainly not the longer one.
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the spring retaining plates. you cant see from the photos that they have the correct pigtail recess in place.

[syncropaddy]

Well they lasted 20 odd years with just paint ...... How long do you intend to keep them? 40 years?

Galvanising components like that is overkill. Properly prepared and properly sprayed with the correct type of paint is all that is needed.

Galvanise spray on the body seams is a different matter

[Aidan]

of the two options the zinc spray and wax looks the best to me, should help to protect all the new welds which otherwise will tend to rust faster than the rest

you can then paint them black and cover them in underseal for that factory fresh paddy approved finish

[hotpod]

excellent.
thanks chaps.
i like the thought of the hot dip getting right inside but apart from that was thinking it might be over doing it.
i shall go zinc spray and paint and wax then. it will look more factory and should be good for longer than the originals.
i am thinking that at the price they (16" arms) are fetching at the moment they could be a good asset should i ever give up on the doka.
but i dont think i need them to outlive me really.

will post more pics when i get them back.

[axeman]

nice work there hotpot, galvanizing is cheap its also constant (covering), very durable, tough and the way forward in my opinion. when i did my trailing arms i only had to re-tap the bearing housing mounts, but this was not problem.

keep us posted

neil

[silverbullet]

I second that on the galv. option. Having done all that work anything else would be cutting corners. Nice welding too

I made up a press tool to re-form the pigtail groove in BW spring seat plates when I repaired my 14" ones, using the pigtail from a scrap spring. Cut off the spigot, get the plate red hot and then get it under the fly-press before it goes cold again, re-fit spigot etc.

The tool wouldn't be any good for making a swingarm repair section though, clearances all wrong for the extra metal gauge etc

PS how did you line them up to keep the offsets and camber correct? Tabs tacked on the bench before you cut them?

[hotpod]

i didnt make a jig for re aligning the arms, just a square. the old arms were so out of shape at the front that there was noting safe to work from.
i had been told a while back that they were square with the arms and it appears to be true. that was also consistent with the fact that when the extensions were squared up with the donor arms, they were sat perfectly on where i had cut off the donors side plates with a biscuit disk.

so i hope i am right. to be honest, the way the extensions fit within the arms, there is actually very little room for maneuver anyway. i knocked them in and lined up the front of the plates and checked them with a square and they almost were. i tacked the front and tapped them till they were properly square then welded them up.

now i have a question about the new bushes i have to go in them. they have a gnarled side and a smooth side. i would guess that the gnarled side would go on the nut side ( i.e. will be towards the inside of the truck when on) but could someone who knows confirm this please?


got em back from the finishers yesterday... hot zinc sprayed and as much powder as they could get on without it running apparently.




theyre gonna make the rest of the truck look even worse by comparison

[jes*b]

Sir Pod of Hot. This is SWEET 16" work. More power to you. What are you proposing re. refurb of bearing housing etc. the backs of mine need TLC I am proposing blasting and paint?

[hotpod]

well, a mate down the road has an extremely high pressure water blaster. he uses it to remove paint from the huge gas tanks which are sited outside peoples houses. it removes everything bar the metal. hes not blasting till the end of next week though.
the other thing i am intending to try over the weekend though is this: http://www.pembleton.co.uk/techpages/derusting.html
the perfect solution ( no pun intended) i think. will be good for all of the socket cap bolts too which are in excellent condition especially considering what they looked like at first.

[jebiga41]

well, a mate down the road has an extremely high pressure water blaster. he uses it to remove paint from the huge gas tanks which are sited outside peoples houses. it removes everything bar the metal. hes not blasting till the end of next week though.
the other thing i am intending to try over the weekend though is this: http://www.pembleton.co.uk/techpages/derusting.html
the perfect solution ( no pun intended) i think. will be good for all of the socket cap bolts too which are in excellent condition especially considering what they looked like at first.

Used that method on the front subframe for Tinkerbelle, used a battery charger as a power source and made a paddling pool out of a tarp for a bath and washing soda for the solution. Worked a treat more info here http://www.instructables.com/id/Electro ... aka-Magic/" onclick="window.open(this.href);return false;