Is she a rust bucket??? Help needed!
Discussion
Hello pistonheads,
I am in the market for a Mk3 MX5 and went to look at a nice one today. The only thing I am worrying about is the condition of what I believe to be the rear subframe under the car. It had an advisory on the MOT in January 2018 for rust to the rear subframe and it looks like someone has gone over it trying to rust proof it. Would this put you off buying the car or is it okay? The rust was not mentioned in the most recent MOT.
I am in the market for a Mk3 MX5 and went to look at a nice one today. The only thing I am worrying about is the condition of what I believe to be the rear subframe under the car. It had an advisory on the MOT in January 2018 for rust to the rear subframe and it looks like someone has gone over it trying to rust proof it. Would this put you off buying the car or is it okay? The rust was not mentioned in the most recent MOT.
If you're worried can you get a mechanic friend to look or an RAC inspection done?
The most likely scenario is an advisory was given for surface rust. Any actual perforating rust would likely be a fail on a subframe. This has most likely been addressed with a wire brush and a generous coat of stonechip.
So, no, not a rust bucket, it's probably OK. With usual caveats as I haven't actually seen it.
The most likely scenario is an advisory was given for surface rust. Any actual perforating rust would likely be a fail on a subframe. This has most likely been addressed with a wire brush and a generous coat of stonechip.
So, no, not a rust bucket, it's probably OK. With usual caveats as I haven't actually seen it.
Edited by Oldandslow on Monday 18th February 01:23
As has already been said, subframes are fairly thick steel so as a comparison I’d expect the body panels to be showing a fair amount of rust before the underside/subframe was at the point that it was rusted to where it was seriously weakened.
Having said that, the picture you posted does make the subframe look fairly crusty. I realise it’s just one photo but it looks like they’ve just splashed waxoyl or similar over the rusted metal, without getting rid of the rust first. In my experience that not only never works and the rust will be popping back through in a matter of months, but it often makes it worse because a) you can’t see it so assume all us well and b) because it’s unlikely there was zero humidity when it was done so every crevasse, crusty spot and pitted surface will have trapped moisture and will be a perfect environment for rust to eat in further.
I cleaned up the suspension and rear subframe of my Mk1 MX5 recently and cleaned up any surface rust before treating, prepping, painting and undersealing/rust-proofing the metal, and it looked smooth and even, not lumpy and too thickly painted like the one you posted...
In short, I’d walk away - there are many many mk3s out there and many which look far better than this and are still very cheap - just not worth the hassle of chasing rust, especially when it’s more of the structural than the cosmetic variety... and unless they have photos of the work being done, you will never know how thorough a job was done or how bad the rust was. A gamble not worth taking in my view, but that’s just my opinion!
B.
Having said that, the picture you posted does make the subframe look fairly crusty. I realise it’s just one photo but it looks like they’ve just splashed waxoyl or similar over the rusted metal, without getting rid of the rust first. In my experience that not only never works and the rust will be popping back through in a matter of months, but it often makes it worse because a) you can’t see it so assume all us well and b) because it’s unlikely there was zero humidity when it was done so every crevasse, crusty spot and pitted surface will have trapped moisture and will be a perfect environment for rust to eat in further.
I cleaned up the suspension and rear subframe of my Mk1 MX5 recently and cleaned up any surface rust before treating, prepping, painting and undersealing/rust-proofing the metal, and it looked smooth and even, not lumpy and too thickly painted like the one you posted...
In short, I’d walk away - there are many many mk3s out there and many which look far better than this and are still very cheap - just not worth the hassle of chasing rust, especially when it’s more of the structural than the cosmetic variety... and unless they have photos of the work being done, you will never know how thorough a job was done or how bad the rust was. A gamble not worth taking in my view, but that’s just my opinion!
B.
Edited by bmv6197 on Monday 18th February 19:06
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