Page 1 of 1

Chassis leg strengthening

Posted: Tue Aug 30, 2011 8:12 pm
by Alex'n'Ane
My chassis leg has just decided to brake, not due to obvious corrosion but where the eyebolt goes through (into the 'reinforced tube section') it has moved upwards, so that the wishbones are resting on the engine bay floor, and I can see a crescent shape of the bottom of the usual hole in the chassis leg. I presume this is due to the reinforcing plate twisting upwards? (I had just fitted new poly bushes so presume the greater loads were the cause of an already weak part to fail) I had exactly the same issue on the other side a year or two ago, but thought nothing of it and replaced the chassis leg as per usual. I am fitting the new chassis leg hopefully tomorrow or thursday and was wondering if there was anything I could do to beef up this section, or if someone could explain the cause of both legs failing like this?

Re: Chassis leg strengthening

Posted: Tue Aug 30, 2011 11:52 pm
by bmcecosse
Corrosion and harsh feed-back from the unforgiving polyurethane bushes.....

Re: Chassis leg strengthening

Posted: Wed Aug 31, 2011 6:50 pm
by MarkyB
It shouldn't need beefing up, just some protection to stop it rotting out again.

Re: Chassis leg strengthening

Posted: Wed Aug 31, 2011 7:21 pm
by les
Image
This is my effort at beefing up the tube area.
View looking from bottom of chassis leg, before capping the leg.

Re: Chassis leg strengthening

Posted: Wed Aug 31, 2011 7:50 pm
by bmcecosse
That looks good!

Re: Chassis leg strengthening

Posted: Wed Aug 31, 2011 10:43 pm
by les
It's a heavier version of the original design.
I think jlh strengthen legs by welding webs inside,linking one side of the box section to the other, in preparation for their coilover suspension.

Re: Chassis leg strengthening

Posted: Thu Sep 01, 2011 1:18 am
by Fingolfin
Would it be overkill or unsafe in any way to get hold of narrow square steel tube and weld it in at the bottom corners of the leg? That'd certainly make it a lot stronger. Like...[frame]Image[/frame]
Though obviously it couldn't run through the existing strengthener around the eyebolt. Maybe that could be modified?

Re: Chassis leg strengthening

Posted: Thu Sep 01, 2011 2:13 am
by rossrox
les wrote:It's a heavier version of the original design.
I think jlh strengthen legs by welding webs inside,linking one side of the box section to the other, in preparation for their coilover suspension.
Not sure they do strengthen it, i have just fitted my coilover suspension from jlh myself and there was nothing to strengthen it... unless i didnt read the instructions properly :S haha.

Re: Chassis leg strengthening

Posted: Thu Sep 01, 2011 7:27 pm
by Alex'n'Ane
I dont think that box section along the bottom would solve the problem, as the issue is with the internal tubing coming away.
I fitted it today and did in a very similar way as to the way jlh suggested.. http://morrisminorowners.co.uk/about393 ... highlight=
The only difference being that rather than fancy feet bits or the curve we seam welded 4 straight strengthening plates in as per the drawing. Its all just additional support and strengthening :)

Re: Chassis leg strengthening

Posted: Thu Sep 01, 2011 8:22 pm
by Fingolfin
Smart! Hopefully that will solve the problem with some degree of permanence.

Re: Chassis leg strengthening

Posted: Thu Sep 01, 2011 9:43 pm
by les
I'm sure the leg modification by jlh was used at some point as a way to 'link' the two chassis leg sides, because I remember wishing I had done the same when rebuilding my chassis. My own interpretation of the reason was to reduce twisting of the leg when fitting the coilovers. Perhaps I gave the impression that the strengtheners came with the kit, whereas I expect they were fitted if they did the complete coilover installation themselves. Unfortunately Jonathan doesn't post here anymore, to confirm or deny.