Paid a lot for a rust bucket MX5

[mightymolecule]

So this is half rant and half asking for advice I suppose. Just bought my first MX5 NC from a dealer. Let’s just say that I spent a few grand more than needed to get a nice example. It’s immaculate up top and has been well cared for with low mileage and great service history.

However, I took it in for a tyre change and found slight signs of rust underneath (no surprise really). It’s been rust proofed underneath so it’s difficult to see the extent of it. I thought I’d check the service history to see what it’s been treated with (dinitrol 2 years ago by the previous owner).

While researching dinitrol and MX5s I accidentally stumbled across some posts from the previous owner (same name, location and mention of my car). He basically said he was having rust issues and did the dinitrol himself because a specialist said the rust had gone too far for them to do it. Sounds like he did a thorough job and he evidently cared for the car, but he made the (probably smart) decision to get rid of it before the problem got worse.

Well now it’s my problem. I suppose my question is, after sinking a reasonable amount of money into the car already (more than I should have paid, truthfully) I'm feeling like I bought a rust bucket. My wife is already asking why I didn’t buy something more sensible… and I feel that my future car buying credibility has taken a knock! I originally planned to enjoy it as a daily for 3 years and then move on, but have no idea how quickly rust issues can develop into major problems? Will it even last that long?

I really don’t want to be spending loads on welding etc. my options are, enjoy it for a year and sell it via WBAC next summer or keep it for as long as I can before it fails an MOT and then asses costs to fix the rust. Am I worrying over nothing or does rust kill these cars quickly?

Edited by mightymolecule on Saturday 8th June 22:41

[mightymolecule]

Belle427 said:

It all depends how bad it was when he covered it up, dinitrol is very good and does contain inhibitors to try and stop the spread but it isnt a miracle product.
Photos may help but obviously these can be tricky to do.
if it wasnt that bad and not an Mot failure id be inclined to leave it and enjoy it as much as you can, you need to re apply rust proofing products every few years really too to keep it working effectively.
If someone refused to work on it i assume its quite bad though.

I don't have photos of the underside but I did see underneath last week when it was up on a ramp. The dinitrol makes it hard to see but there's bits of rust on the sills (the main area). It's sort of flaking off a bit. Engine and gearbox are both dry. Not bad enough to poke holes in with a screwdriver but enough to make you wonder what lurks beneath. I think your advice about enjoying it as much as I can and sort of leaving it until it becomes an issue (MOT failure) is probably the way to go.

[mightymolecule]

bmv6197 said:

Sorry to hear - always a bit of a sinking feeling when you buy a car then find out all is not as rosy as you thought it was. Still, that’s part of the rollercoaster of being a car enthusiast.

Rust is always a complex business - no two cars’ history are the same and given the last owner has been working on yours previously, it’s pretty hard to judge. My advice would be don’t let it spoil your fun - it’s a car, it’s fixable, and it will just be about a gradual journey of discovery which will ultimately help you determine what the right fix is, even if the fix becomes to sell it on at some point…

My NA MX5 (1995) is one I’ve spent 16 years slowly getting sorted the way I wanted. About 5 years ago I decided that I wanted to get the underside back to pristine shape (given the rest of the car was all sorted by then). I just did each corner as a separate weekend project - up on jack stands, I took the wheel off of one corner each weekend (easier if it’s not your daily and you have a garage), removed all plastic covers etc, cleaned everything back, then any surface rust got ground back, bare metal treated, primed, painted, then undersealed. Along the way some bits were better than expected, other bits worse and required more work. And sometimes you end up having to replace a few parts but they’re pretty cheap anyway! But that’s all part of the journey. Messy and time consuming but satisfying and you really end up fixing things properly and knowing every part of your car.

Take your time, and take the positives. And you’ll be happy with the result.

Good luck!

Yours looks great! You must be pleased with the result - well worth the work if the rest of the car is sorted. I'm not mechanically minded and unfortunately also don't have the tools/space to work on the car, so I'm reluctant at this stage to invest anything in improvements etc until I can gauge how bad the rust is. I'm hoping the next MOT (next year) might give me some indication.

[mightymolecule]

Hugo Stiglitz said:

It all depends, if you can easily poke holes in with a screwdriver then your probably looking at a full strip down for peace of mind?

The fact that the previous owner used it to mask? the rust or did do so after some work first? Are his posts quite explicit?

You can't poke holes in it, but the dinitrol is flaking off in places and rust is showing through. The rust is mostly along the sills. The previous owner did the dinitrol treatment two years before selling it, so I don't think he did it purely to mask. From the paperwork that came with the car, it looks like he invested heavily in it throughout his ownership and didn't take shortcuts. He mentioned in the thread that he did the dinitrol himself because a specialist said they thought the rust had gone too far. He apparently wire brushed it all and cleaned it up before applying, so did a proper job. He got into every cavity and took him ages apparently. He then touched up the dinitrol annually thereafter. But it sounds like he came to the decision that he'd be fighting a losing battle and decided to sell it before it lost its value.

I think where my head is at now is to enjoy the car for another year and see what the next MOT throws up relating to rust (if anything). I don't know how quickly rust progresses, so not sure if I can get say 2 years out of it before having to invest in further rust treatment or not. I know at this time I don't feel comfortable spending £1000 or whatever to do an underbody treatment if the issue could potentially return. It's a shame because it's such a low mileage car and is immaculate up top but the rust is something that concerns me.