Club 80-90 Forums

Hi,

I am in the process of replacing the Outer Trailing Arm Mounts on my 14" Syncro. They were both quite badly rusted and not held onto the van by much so I bought 2 new replacements from Brickwerks. Before cutting the old one off I made a jig and welded it to the van. Also I fabricated the repair for the chassis member and used Clecos to attach it to the Van. This is shown in the following image.



Once I was happy I carefully cut the remaining threads of metal still holding the old mount and removed it. However when I put the new mount on the jig I can see immediately that all is not well. Something in the dimensions does not match up.




Comparing it with where the old one matched up with the repair piece there is approximately a 9mm difference.


Comparing the new and the old even accounting for a bit of corrosion there is approximately a 9mm difference.


So here's the thing the helpful guys at Brickwerks measured an original one which seems to be ~47mm which still seems a way of my original. All the reproduction replacements seem to measure about 50-51mm

My only solution appears to be to have my new ones modified by having the slots milled longer until they are closer to the original. I think I may need to have the small horizontal slot welded in as the modified slot may be a little close for comfort. As far as I know it doesn't actually do anything on the van, perhaps it was used as a original jig point.

Any views or experience of this gladly received.

Peter

Do you know how straight your rear wheel was sitting initially? Look at the start of my thread for an example of “way off”. My mount was slowly moving up into the van...

Otherwise you seem to be on the right track. Lengthening the holes will allow you to place the mount and still get the trailing arm in the right position.

Do you know how straight your rear wheel was sitting initially?

Roger that is a good question! However the suspension mount was fairly well attached to the horizontal chassis member so my feeling is that it would have been pretty much straight before I started.

Regards

Peter

Anybody perhaps have any access to original drawings part numbers are 251 803 198 for the rear right and 251 803 197 for the rear left.

Peter

I have measured the replacement part accurately now. My thinking is to get them machined to the measurement they should be.

Well looks like I have the result of measuring 2 original brackets and working out the average dimension to get machined:



Bit more measuring on the van required of the angle of the old bracket then off to my local engineering workshop for help

I wouldn't have thought you need to get it cut out wildly accurately, I think what you are trying to do is ensure that when you have welded on the JP, you have enough adjustment to get the rare wheel vertical, and straight for-and-aft. I don't think there is any such thing as too much adjustment.

It occurs to me though, the offending bit of rear crossmember poking past the corner of the JP, could be hidden by the JP moving forward. It also occurs to me, is the JP going to be touching the base of the inner sill when you've shuffled it downwards? Or are you replacing that part of the inner sill - I guess so as there didn't look like there was much left.

See page 13 of my thread for (my heath robinson method of) positioning the rear JP. Other methods are available.