2b Chassis Cracking

[Grim]

On my 2000 2b, the plate to which the rear subframe mounts to has failed on the passenger side, along the heat affected zone of the weld to the side of the (see photo).

 

Can anyone supply me with pictures of the chassis in this region so i can tell what is still holding it together, if anything? (I didn't build my car so have no idea, and the subframe obscures it).

 

Does anyone have any suggestions for fixing it? Welding it up would be possible, but does not strike me as a permanant solution if this region of the chassis is not strong enough. I had thought about welding it and then inserting a fairly thick steel plate between the subframe mounting and the existing plate, and fixing / welding it to the chassis tubes.

 

In the image, you can see the bottom of the side body panel at the top, and the subframe mount at the bottom, and the large tear along the weld.

 

Andy :boohoo: :boohoo: :boohoo: :boohoo: :boohoo: :boohoo: :boohoo:

 

EDIT-- Looking through the robin hood brochure, it appears there's nothing holding the plate on at the back, so it would appear to be completely detached.

 

[Dave R]

cant find my early build photos but i recall that this is just a flat plate with one edge welded to the bottom of the side chassis tube ?

maybe worth a call to trickey first off ?

 

dave

[Guest Petemate]

Don't like the look of that - along with others probably, going out in the garage to have a GOOD look.....

Pete

[Dave R]

just checked the first build video, its about 25 mins in if you got it grim

the subframe is also located on the pivot bolt on the outer bush

guess thats whats stoppin it from falling off :boohoo:

 

lookin at the video its scaery how much will maybe have to be removed to stiffen it

there is a chassis tube above it that a right angle piece of plate , remaking the bit thats cracked could be attached, but not gonna be easy on a completed car :gdit:

[Guest TerryBarry]

Here's about the best pic I can come up with - this is the offside mounting

 

Before anyone comments, the floor ended up on top of the mounting plate

 

Is your chassis stainless or mild steel ??

[Guest TerryBarry]

I've airbrushed some of the "camo carpet" in the area of the plate - hope this is a bit clearer

[Grim]

Thanks for the pictures. It's a stainless chassis.

 

I think i'll either get it welded up, and then reinforce both the drivers and passenger's side with a second plate underneath, bolted to a peice of 40mm box section running across from one side of the car to the other, or weld in an entirely new plate of thicker section, with the box section to the other side. If anyone has any better ideas, please say so!

[Bob Tucker]

A lot of us fitted a full width angle iron durng the build to take rear seat belt bolts & seat fixture bolts. Maybe thats stopped the plates flexing.

Have you fitted anything similar?

PS mines a mild chassis.....from your pic it seems simply that the weld has failed.

 

I'd talk to the factory about it

Bob.

[Guest Petemate]

Had a look earlier. Can't see enough to judge the condition. But - as the outer trailing arm pivot bolt goes towards providing some support, and in the light of my massive plate (5mm, 4" wide) that goes across the rear and is bolted to those plates, I don't think I'll have a problem. I'll be keeping it under observation though....

Pete

[Dave R]

surely the plates cant or shouldnt flex when the rear suspension is bolted on

you cant get much stiffer than the tube thats made from ?

 

no better ideas though

[Guest Battery Bill]

I wonder if the holes were not quite right and it was forced into position, then was always under strain!

Like Bob says most cars have some sort of beam across that area.

[Grim]

There's no angle iron going between these two plates (which is where my box section will go, just in front of the subframe). It's not the weld itself that has failed, but the plate itself, in the heat affected zone near the side of the weld (see diagram).

 

I'm not entirely sure what the inside seat belt mounting is now, i'll have to check!!!

 

I suspect it will have been caused by not having a beam here, and excessive grounding (always happened more on the passenger side).

 

Andy

[Guest Petemate]

Regarding excessive grounding, good point. Enthusiastic cornering and navigation of speed humps prompts me to regard my next project as the speedy removal of the "cups" and replacing them with short bolts & plates. B***er - seat & floor carpet removal!!

Pete

[Guest carl leonard]

Place a piece 2"x 2" angle across the car and bolt \ weld into place. As mentioned this will allow the seat belt mounts to be attached and 'seat' bolts can also go through.

 

I've just been out to check mine and everything appears Ok after 2 years.

 

Carl.

[Guest salty_monk]

The Stainless chassis is sure to be more prone to this than the mild steel ones... Wonder what Chris Brown has done different to you as his is stainless & he has had no problems as far as I'm aware...