Well I found it but your not going to like it much. The aluminium body has cracked close to the bottom mounting hole for the rear exhaust hanger. I have a 2 inch long split. I have made up this plate to prevent it getting worse and it certainly has stopped the god awful noise when hitting small bumps.
not good news, i understand that the brackets are just riveted to the aluminium body panel.
How many miles, and did you have cracked exhausts? Just trying to understand if there was potential extra stress on your bracket. Looking for another reason than "they all do that sir"!
The brackets are actually bolted in place but the captivated heads do look like large rivets. They are held in place with the penny washers you see here and nylock nuts. I have used a spring washer and a standard nut as the plate I have fitted stopped the nylock nut from fully engaging. The body is quite new, 2014 spec and was only fitted 3500 Mls ago due to the old girl being belted up the backside by a range rover. I used to suffer from lots of split bobbins but since the heavier 1.5mm exhausts were fitted the bobbins have stayed intact. The body does vibrate an awful lot around the rear mounting. The front mounting seems much more rigid. The split is broadly horizontal and just below the bottom bolt hole. The split does not emanate form the mounting hole. Local dealer is talking to Morgan so we will see what happens. I think vibration is the problem. I just hope it's a one off and maybe a bad pressing. For a truly effective repair I would drill additional support holes in the bottom corners. Will wait for Morgan's response before any further mods
When i next have mine out and running i'll have a look and see how much vibration is in that area.
7000 miles so far and no exhaust bobin/exhaust failures makes me hope its a tolerance build up leading to more stress on the bracket through vibration.
Matty, Maybe the heavier exhaust and bobbins (heavier too?) are at fault. The rear plates on my car (2012) look to be glued on plus bolted in the boot. I wonder if your body was doing the work of the bobbins? I also wonder if some of us should consider making a bigger back up plates for the exhaust pipes? Amazing how much development work all of us are doing for Morgan.
Yes I'm sure your right. The body is definitely vibrating quite badly at this area. Aluminium will of course work harden and I am sure this is what has happened. I don't know yet what Morgan's response will be but after talking to a few of the old hands at Combe Mill this weekend I'm very sure that we should face facts and realise that the owners will have to make the best of it and engineer most of the solutions to our problems. In a funny sort of way it will enhance and speed up the bonding process between the owners of older and newer models
Hi Still had no news from Morgan, but that's not really a surprise. The crack is no longer making horrible noises every time I hit a small bump in the road so I guess my plate is working. My only worry is, have I just moved the stress point to the edge of the plate. I'm not an expert on the way cracks behave or indeed a metallurgist. Any ideas welcome. If a large backing plate is the way to go, I'll fit the other three mounting points with one. I would also get them manufactured locally for sale at cost to anyone else interested.
Matty, did you drill a hole on each end of the crack to stop further cracking by notch effect? If not the crack will slowly expand further even with a supporting plate.
Hannes once: Green M3W; 2013 now: Red 4/4 Sport; 2011 and some practical cars for use in real life
