- My model of MX-5 is: 1995 1.8i
- I’m based near: northamptinshire
- I’m looking for technical help or recommendations on: rear sills suspect:
Recently bought a 95 mx5 which I have to say is in extremely good order 47k on the clock garages one lady owner from new etc.
I may be wrong but I’m sure the sill underneath should be completely vertical with no return, well I’m feeling a return lip underneath at the rear sills at best I think it shows it’s been repaired at worst it’s had a panel put over a panel which is pretty scary, any ideas/suggestions?
1 Like
Get it on a lift and check it out. Plan for some metal work though…
1 Like
.A repair is not the end of the world. Loads of us with NAs have had repairs done as MX5s are buggers for rust - far worse than an MGF weirdly (some more than most 
) and if it’s done properly it’s fine.
I’ve just been out to check my sills. I have a little lip and I’ve had them repaired. In fact I’ve had the entire outers, inners and what was left of the middle strengthener pulled out and remade (except the outers are pattern replacements) - I saw it being done.
Your car should have drain holes at the front and back in the structure of the inner meeting the outer sill. Loads of pics on the internet of them… Particularly at the back where the inners and outers meet just ahead of the wheel well they get crushed by idiots with jacks or disappear in a bodged repair. Do yours look serviceable or crushed to oblivion or not there.
Then lift the sill covers and shine a torch into one of the inspection holes while putting your eye to another. Really it helps with a borescope but you can se a fair bit of the general condition with the naked eye. There can be grommets inspection holes in the front of the rear arches too.
Then feel round the arches. Is it solid or poor.
If it’s all good then you should still get sympathetic with your car. She’s an old girl almost 30 but mileage means nothing for an mx5. In the US they are running one to a million miles. But rhe do have a massive rust reputation so it means regular rust proofing and cleaning and draining the sills.
1 Like
Sound advice and after watching a couple of utube clips it’s clear that the pattern replacement outer does in fact have a lip, I would have at least notched it out where the drain hole is though and something I may still do as they are still visible and not damaged I have a mate (old work boss) with a two poster so I’ll come back here when I’ve had a good look
Lets see some pics to advise.
M-m
1 Like
Can’t borrow the two poster for a month but I will try to upload some high res pics soon
1 Like
Have a look at The MX5 Restorers You Tube channel, they repair cills everyday of the week. There’s some horrendous rust cases there and gives you good insight what to look for. The cill structure is quite complicated so not cheap to repair if really bad.
2 Likes
On a pattern sill you get more of a lump than a slit. On mine the restorers made neat notches in the inner sill so you feel two little holes as you run your finger down inside of the edge of the inner. It’s quite nice and I could put tiny little rubber plugs in it to keep out the water gnomes with their tiny buckets of sh1ty water.
1 Like
Yes Bernard I already watch the mx5 restorers utube channel and have what your talking about
1 Like
Sorry, seen what your talking about
1 Like
Isn’t there a lip along that area ? To strengthen the vertical lip where the jack goes ? I’m only guessing …
Very possibly!
1 Like
She’s giving me engine trouble at the moment so my attention is on that now🙄
1 Like
Bless All of you and your little MX 5’s As with all things MX5’s have their little illnesses , I’m sure they were not meant to last 15 / 20 years, I take my hat off to all those who have kept some remarkable older MX5s on the road … incidentally We have a Retyred meeting today Wednesday At the Woodman pub Standford Rivers Essex all welcome .lots of room in a very spacious garden And car parking is plentiful too. .The weather forecast looks perfect for a run out in the MX5 Hood down etc…
Best regards from Ray Hill Epping Essex…. Ps. The meeting went very well and was well attended by a lovely mix of MX’s and people ( about 30 ) including a couple of stunning mk 4,s …
The sill structure is basically three pieces like [ | ]---- where “----” is the floor. I say basically because the last 40cm ish of the rear middle reinfocement piece is curved not straight and is spot welded to the outer sill and the bottom of the rear arch panel.
The outer sill section is the largest piece of the three and at the bottom of the OEM pressing it has a 20mm ish vertical with a 5mm ish 90 degree return, so the return lip is normal. I think the lip is meant to hold seam sealer so the three sill pieces can be seam sealed effectively at the bottom.
The OEM outer sill isn’t notched, it has two pressings both front and back to allow water to drain through the notching in the middle sill and inner sill at the front and inner sill at the back. The OEM holes are a bit small and clog up
The sill jacking points are between the front and rear sill drain holes, the jacking points are made of a pressing in the inner sill and they’re not particularly strong although the front is stronger due to the near vertical section of the middle reinforcement piece. If you can feel the pressed stiffening ribs in the jacking points then it’s highly likely to be an original inner sill because it’s a total PITA to remake them and look OEM. The other tell-tale is the very back of the inner sill panel, the original is curved vertically and curved inwards and if it’s been repaired they’re often squared straight off as it’s easier.
There’s a big Northampton community that meets at Sywell, I’m sure if you turned up you’d get some good advice / opinions etc
1 Like
Thank you that’s extremely helpful