Rear chassis rust removal and protection

[AJSGSE1990]

Finally had some time to crack on with the car. All the rear elements are off, mostly pretty easy after having spent a lot of time with steam cleaners and degreasers taking all the Lanoguard off. Then a week or so of daily spraying with my new best friend Rocket TT which seems to work much better than WD 40. Brake lines are shot and I will need to replace the lot.

Plan now is to further rub off some surface rust, then get some phosphoric or similar to take the rest of and epoxy primer it. Is there anything I am missing or should try and do? I am going to try and find somebody to sand blast the suspension arms and hubs, although I do not like the idea of trying to remove those allen heads in the hub. They do not look like they want to come out.

Cheers.

WhatsApp Image 2026-05-31 at 16.21.30 (2) (Small).jpeg

WhatsApp Image 2026-05-31 at 16.21.30 (1) (Small).jpeg

WhatsApp Image 2026-05-31 at 16.21.30 (Small).jpeg

[dapinky]

I have usually found that all the suspension components strip fairly easily with just a wire brush to get rid of the worst, and then using phosphoric acid. I managed to make up a suitable 'bath' for the lower wishbones using a sheet of polythene DPC and sone bits of 4x2 timber.

I have got a sandblaster, but no cabinet, so I use it infrequently with parts still on the car (but it is wasteful of abrasive as it can't be recycled).

Epoxy primer (POR15 in grey is a good match for the Lotus chassis) or zinc-based spray paint are both good, chassis black paint is okay, but powder coating isn't really recommended on components where it could get cracked/chipped and allow water through. I always finish off with a clear wax spray (Bilt-Hamber Dynax UC), but that is just my own preference.

[AJSGSE1990]

I have usually found that all the suspension components strip fairly easily with just a wire brush to get rid of the worst, and then using phosphoric acid. I managed to make up a suitable 'bath' for the lower wishbones using a sheet of polythene DPC and sone bits of 4x2 timber.

Good idea and thanks for the epoxy tip. Had a crack at the chassis with the angle grinder and rust dissolver and its already looking much better.

Cheers,

Andrew.

[Tuga2112]

on the topic of rust protection and prevention.

i have recently heard that tannic acid is a very valubale add on to the phosphorinc acid solution. i havent tried it yet. but may be worth investigating the topic.

as far as doing the job.. well done, keep going. i need to do the same eventually. but i think im going to wait a while before my yellow car gets its suspension removed again.

[AJSGSE1990]

but i think im going to wait a while before my yellow car gets its suspension removed again.

My nemesis are bloody ball joints, just cannot get them off without damaging the boot. Also, disk is seized on so was cheaper to buy hubs than spend all that time hammering at them. Soaked for a week in releasing agent and hit pretty hard, then proper clutch puller, nothing...more stubborn than my teenage daughter!

What fun

[Tuga2112]

i find taking it all apart to be pretty trivial.
but i have 10 years of stocking tools and making contacts... i have access to a 10ton press.. and on weekdays a 30ton press. mapp gas at home and oxy at the restoration club... the lotus owners group has some folk with a lot of knowledge. specially the ones who have restored the older cars.

i tend to go to their meetings mostly for that exchange..