Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Cracking Job

Very poor weld penetration Morgan!



Both sides too

Ouch, the shocks with bump stops don't look original though,
What car is it and how old?

It's a 2012 Duratec Plus 4.

And running BCC supplied anti-tramp rear leaves made from proper 5160 steel and correctly tempered by Owen Springs just outside Sheffield. Mulfab10mm lowering/axle centering blocks are in place, but the whole setup is paired with SSL supplied Bilstein dampers with the correct stroke for the job.

As with all Bilsteins, they come with proper OEM grade rubber bushes, not the dreadful bubble gum/cheesium bushes you find on AVOs, these German made dampers also use 55mm OEM grade conical closed cell polymer bump stops rather than the invisible 'we forgot to fit bump stops' that didn't come with original Morgan dampers, and even some of the aftermarket dampers that claim to be an upgrade!

On close inspection of the failures, it was immediately evident weld penetration where the hoop tube ends were joined to the chassis mounting brackets was nonexistent!

The original poorly welded hoop ends we're removed, and new we're fabricated from cold drawn seamless roll cage tube, the opportunity was also taken to extend the new hoop ends by 30mm to increase the damper travel under compression by the same distance.

The new hoop ends were also socketed, then properly seam welded at the joint with plenty of heat and excellent penetration.



It's not seen here, but the outer sleeves of the socketed joints were also drilled, then plug welded to the inner sleeve for extra strength.

Here's the first trial fit.

The hoop was then offered up one last time and with the dampers trial fitted, it was then properly squared up before all the final checks were made.



Given the 30mm hoop lift all clearances (rear edges of marine ply inner arches to axle, diff nose to hoop, prop to prop tunnel) were very carefully studied, and before tack welding. The hoop was finally properly mig welded, this time with excellent weld penetration that put Morgan's very poor welds to shame.

The Mulfab 10mm blocks were retained to give a nice 22mm arch gap, however, the 30mm hoop lift now gives far better compression travel, and what people often overlook is the blocks actually add 10mm of rebound travel. The end result being far more rear suspension articulation oveall with nothing hitting, and all of it from full compression to full droop being properly controlled by the excellent quality and firmly damped Bilsteins.



All this with the wheels still nicely centred in the arches.



A big improvement over the original very archy look, and the dreadful off-set axle arrangement shown below



The hoop is now infinitely stronger than it was when Monty left Pickersleigh Road in 2012, and a quick bounce test shows good rear suspension travel, again it also proved nothing hits!

https://www.youtube.com/shorts/jVYEwMCUsj8

Compare this with my friends TVR Chimaera also running Bilstein damping (coil overs), and we can see Monty has perhaps a touch more travel, but is definitely more compliant with both setups exremely well damped exactly as one would expect from Bilstein.

https://www.youtube.com/shorts/PwklTEapWQQ

Job done

As my car was delivered just before yours, Montegue. Thought I’d better take a look at MMC welding on my hoop.



Mmm not great. (Off side)

I'm not defending the Factory (MMC) but the hoops are bought in
Probably the same Co that made the tubular Three Wheeler chassis with latent cracking issues

The concern is that the factory accepted the quality of the welding and went on to fit it knowing it was rubbish......

It is not very serious that job and also dangerous.
What about the roadster series?

The early long door Trads had that issue with fractured damper mountings on the brake backplate. So when you strengthen one place, the next weakness emerges. Bottoming out dampers won't help at all, and thats why Rog's progressive assists are so good.