Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Chassis corrosion to 2015 onward cars

When I rebuilt my 4/4, I replaced the corroded gussets ... made sure they were properly fully welded at all edges top and bottom then brushed the welds with mastic to stop water wicking between the gusset and the chassis rails ... one less metal to metal water-trap 🙂

K

Well done K. The Morgan chief designer and I split a couple of bottles of claret one night over our dinner table. He told me he had mused lengthening the gussets all the way to the very front of the chassis allowing the harmful forces at the bulkhead to be directed harmlessly right off the car rather than to a point midway. He had other ideas for the chassis as well. I have seen cases where owners remove or ignore gussets...especially in a chassis replacement.

I have great sympathy for UK brethren. I didn't realize the much greater difficulty in keeping a trad there until I kept a mog there myself for a decade. Salut!

L.

Since this thread was started every car that falls into the age bracket that I have had in via the workshop has this rust issue

Galvanised is the way to go if you want longevity. However, adding extra protection with underseals plays a big part too but even then it needs regular inspection and topping up. Waxoil, Bilt Humber ( what I ised) give that added layer.
Didn't the epoxy type paint used on the ARP cars start to break down? The Bilt Humber coating didn't harden so resisted chipping and peeling. I also sprayed the wooden rear inner wings/wheel arches with it. Aerosol or bulk with a Shutz gun/compressed air. Eastwood black chassis paint was used on the rear axle, various metal bits and even the wooden floor. Bought from Frost.
A hands on attitude helps with Morgans, otherwise get someone to do it.

For a post 2016 car what is the best preventative measure? A rust kill treatment in the seems / Dintrol?

Regular inspection is the best approach. The triangles at the corners of the bulkhead seem to be vulnerable, and if you have a small drilled hole in the upper layer, fill it with ACF50. Forward facing sections of the chassis get gravel rash. The most vulnerable is the double skinned crossmember behind the seats.

Black Dinitrol will protect it. I asked for the honey coloured wax coating, because it's easier to see what's going on. The autophoretic coating is not powder coating and my experience is that it doesn't lift like powder coating. The gravel rash on mine has stayed as pinpricks on the coating.
Nothing beats regular checks. It's the same with the galvanised chassis. Better protected, but corrosion can still get going, and produces a white powder.

I use two aluminium deflector plates over the exhaust mountings, to keep the crud off. The front section is angled upwards. The main section is horizontal. The angled section is blasted by road grit, as if its been grit blasted, which it has. The horizontal section is untouched. So the forward facing sections of the chassis get blasted constantly by road grit.

If you’re in for long term ownership the best way is to avoid driving when there’s salt on the roads

Well fellow fly fisher. Keeping it clean and inspections are good as Dave said. If it gets dirty let it dry then use a brush. ACf-50 is a great penetrant so start here, spray that in and around all seems and cavities. Now here's the thing, it dries, it's meant too! so let it, I'd give it a couple of weeks before commensing to the wax treatment.
I have tried all wax options and in my opinion Dinitrol is the best. Black under the Morgan is the trad used by the factory so I use that rather than clear. Make sure you are happy with the chassis before applying it, in that there's no loose paint or heavy rust. Here's a top tip, if you need to remove loose paint or rust (gained from a lifetime of experience!) Scrape it off and sand it clean then treat all bare or metal surfaces retaining evidence of rust to a brush on coat of hammerite kurust, paints on like water and when dry turns any rust remaining to a black solid finish. Don't be tempted by the spray version as it's like a lacquer and leaves a soft finish.... nowhere near as tough as the liquid which is solid like the metal itself. It will also protect the metal surface and prevent further rusting.
Now don't go painting it prior to waxing, it is the paint that causes all the ongoing problems. I've been a Land Rover man all my life and it's the poorly prepared chassis' during manufacture which have been painted that cause the chassis to just keep on rusting no matter how hard you try and stop it and how diligently you apply the wax. The chassis already had loose paint before the car hit the showroom and the moisture had already got under the paint and started its evil mission. So, the chassis starts to rust under the paint and wax and eventually blows the paint and it's wax coating off revealing a rusty surface starting especially at weld areas.

As a young man I wondered what the hell I was doing wrong and it drove me to despair! but life passed and I worked it all out and that was that GKN failed to clean the metal properly of it's protective oils and splashed a bit of satin black chassis paint over that so it was destined to fail and quickly too!

So let's look at your car. The coating you have is a great improvement on the sprayed on earlier examples but nonetheless it's no match for galvanising. So your first task is as I have already said... preparation finishing with ACF-50.. When ready to move to the next stage you will need two types of Dinitrol wax. The first is a lighter version designed to penetrate between gaps in seams and is good for internal cavities as well... it gives confidence in knowing that even though you cannot see your efforts you know the wax will creep into every possible gap and surface and it tends to remain slightly softer than the next coat which is a harder under body coating. Again though, I'd leave it a week between these coats as the first will need a little time to really do its job of creeping everywhere.

The best way to apply it is using the Shultz gun cartridge system and an air compressor, buy the gun from them as well as it has the best spray pattern which is adjustable and allows you to spray like a pro even if you have never done anything like it before. it also comes with the screw on flexible lance to allow you to apply it into cavities ir difficult to reach areas. You only need a cheap compressor which you can use to blow tyres up when you have finished the job but every few years I find it good to apply a 50/50 mix of wax and white spirit to the surface as it helps keep the wax to retain enough ability to creep if damaged and self repair small exposed areas.

Now you might think this is starting to sound expensive, well nothing is cheap but if you got someone who really knows what they are doing and applies it correctly then your bill will come in close to a thousand pounds, well the best part of it anyway. I could get you quotes for £350 all over the place but I guarantee it'll probably be a waste of money. Look up a company called before and after and he'll explain it so much better. He'll do an excellent job. give a 10 year guarantee and if anything does go amiss he'll repair and retreat it, Last time I looked, about ten years ago it was £875. I do my own as I'm ...well, obsessed with doing it correctly. I have literally just finished my recently imported from Japan, new Jimny and It was the most difficult and involved vehicle I have ever taken on. The Morgan in comparison is a doddle with no real hiding places. most important areas to make sure you get right are:

Wing to body seams, rear cross member behind rear wheels, the rear, very rear ash timber crossmember where the rear number plate can be mounted. and the triangular Webb chassis strengtheners at the fire was/ bulkhead. There is more to consider here with your vehicle as it has come to light that these Webbs are a problem with 2015 cars on.

I'm happy to help if you would like to discuss anything in greater detail. Martin

I have repaired a customer’s car that’s 2019 with 4000 miles on the clock,and never been out in the rain and that was still rusty on both the chassis legs and gusset plates,,unfortunately from the day the chassis was welded together the rusting process starts,if your going to put two pieces of steel together and not treat any of the metal then unfortunately it’s going to rust

Also not helped if the bare chassis has been stored outside...