replacing trailer suspension

scuby

Hi,

thinking about changing the suspenson on my roller coaster 1 trailer. The existing suspension is not looking great !

I have bought 2 new suspension units, similar to the attached : http://www.towingandtrailers.co.uk/cgi-bin/trolleyed_public.cgi?action=showprod_SU075X44&category=126

just wondering has anyone here removed the old axle/suspension units and replaced them with similar ?
From looking at the trailer, i can remove the U-bolts to remove the axle/suspension.
Would i be right in saying that i should get a length of box iron same length as the existing axle, (get it galvanaised) and bolt the new units to it and the frame of the trailer. I;m just not 100% how to go about attaching the whole thing back onto the frame of the trailer.
Anyone have any hints/tips/pics of you own trailers....

cheers

Talent

From the photos the existing ones look OK - the important thing is the ride. There's bits of very stiff rubber inside to absord shocks and bumps and they take ages to wear out.

The photo I was hoping to see is the underside of the unit. There's a plate with 6 or 8 holes through which the replacement unit is simply bolted (rarely welded) to the trailer. If bedly rised you might need to grind off the old bolts and perhaps drill new holes.

Talent

Oops - sorry about typos.

"Bedly rised" should read "Badly rusted"

fergal.b

We had a post a few weeks ago about the same type of trailer, have a look at zacmorris photos here http://www.boards.ie/vbulletin/showthread.php?p=79461170

As Talent said if the rubbers inside the boxing are good you should be fine, my axel looked quite bad but after I striped it down and cleaned it up it came out fine http://www.boards.ie/vbulletin/showthread.php?p=76136230

I think with changing to a new axel you will have to take into account the ride hight and weather the trailer supports are strong enough to take that type of axel.

scuby

thanks for the replies.

i have attached a pic of the new suspension units. If i rempoe the existing Axle, would a length of box iron the same length be ok ? any suggestions on how best to then attach the new "axle" to the existing frame along with the new suspension unit ?
been look on net for similar set ups. might mail zacmorris for a pic of his new set up.

Talent

Scuby,
We need to see the underside of your trailer exac tly where the old units are attached. Then we can tell you what to do. In an ideal world (I know, nothing's perfect) it's simply a matter of unbolting the old ones and bolting on the new ones. Is there anything different about this one?

BTW one good thing about replacing those units, even if the old rubbers are still good is that you get a new hub and, presumably (and more importantly) bearings.

scuby

the 2nd and 4th pic should show the underneath, but will take a few more pics this evening for ye.
The existing suspension units are built into the axle. Where as the new units are seperate units.

The new unit, comes with a grease nipple on the hub, so i can grease the bearings without talking the hud off, the centre of the wheel also has a little notch for the grease nipple when fitting the wheel.

i originally went to just get new wheels, as they are not great, so decided in a moment of madness to get a new unit and wheels :0)

Talent

Are the units inserted inside the box steel axle, and is that axle set at an angle to the frame? If so I can see you have a problem. You have not obtained a direct replacement for your trailer - what you need is a unit without the flange with the holes for bolts.

And even if you get a directly comparable unit to the old one, you are still faced with the task of removing the old unit which, unless you are a dab hand with an angle grinder and a welder, may be extremely difficult. Will the old units simply slide out of that box section? Otherwise you are faced with removing the axle (angle grinder) and I don't know if this isn't going to weaken the existing frame as the old axle is set into it.

You also need to get a plate welded onto the frame with holes to match the holes on the new units. Sometimes these things can be done using a series of U-bolts but welding is far more reliable.

I cannot understand why the axle box steel is set at an angle. Perhaps that was done to achieve greater clearance from the gound. Will the new units provide the same clearance, I wonder?

I think you face two choices (1) return the new units for a refund or (b) give the job to a competent welder.

fergal.b

scuby wrote: »

thanks for the replies.

i have attached a pic of the new suspension units. If i rempoe the existing Axle, would a length of box iron the same length be ok ? any suggestions on how best to then attach the new "axle" to the existing frame along with the new suspension unit ?
been look on net for similar set ups. might mail zacmorris for a pic of his new set up.

I think zacmorris had to buy a new frame axel from parnell trailers "Indespension" it was about €250, by the time you get the parts to make up an axel and weld it up you will probably be looking at the same money and may not have a trailer as strong as you had to start with.

scuby

the old units are built into the axle itself.

If you look at pic 4 from original post, the axle has a u shaped length of box iron, and then another "spacer" length above it, and these are attached to the frame of the trailer by U-Bolts.

i have no problem in removing the old u-bolts with an angle grinder, but my issue is in getting a bar to replace the existing "axle", and attaching the new units to it
The axle is at an angle on all roller coaster trailers, probably something to do with the suspension unit's and the torsion/rubber set up within the axle, for weight bearing.
http://www.indespension.co.uk/Trailer-Parts/Roller-Coaster/ROLLER-COASTER-1-UNBRAKED.html


I might try contacting indespension tomorrow or call to bronwlows in cork

fergal.b

I think your axel is also part of the frame with a spacer bar in-between the two. The part you are looking for should look like this, the suspension and frame are all one unit.

scuby

think you are right fergal... thanks for all yer help

martin46585

Since you al ready have the suspension units a complete axle may be no longer an option,
But here is a link just in case.
http://sbstrailers.com/product_display.asp?m=4&c=20&ProductDisplay=188
You other option at this stage is to mount the new units inside a channel, as in my case I ordered 750kg suspension units, and got a channel folded to the exact size of the mounting plates, made from 6mm plate and then galvinised, total for the channel and galvinised, 45.00euro.
Then u bolt to the chassis.
The only issue you will have is the ride height, will be minus the box iron spacer...if you follow..
Will post a pic later if needed...

scuby

hi martin,

could you post a pic of your set up

cheers

zacmorris

fergal.b wrote: »

I think zacmorris had to buy a new frame axel from parnell trailers "Indespension" it was about €250, by the time you get the parts to make up an axel and weld it up you will probably be looking at the same money and may not have a trailer as strong as you had to start with.

Hi There,

Just picking up this thread now.

Yes- I had to replace mine which was €243 inc VAT from Indespension (Parnell Trailers) in Dublin. Was a very easy job (as mentioned by Fergal and a few other members).

HOpe you get this sorted asap!

Cheers.