Small hole - MOT failure?

[GheeBhow]

Hello all,

This is my first post, so hopefully I've got the posted image business right!

What do people think about this small hole I found whilst rubbing back my otherwise very good sills - is it likely to end up as an MOT failure on the grounds of excessive corrosion too close to the seatbelt anchorage point? What do you think? It's certainly within a few inches of it - you can see the anchorage point behind...



Thanks,
Neil

[MoggyTech]

Technicaly it is an MOT fail, but most testers would never detect it, as it's all covered by the sill kickplate. Even if spotted it looks like very local corrosion that has not seriously weakened the structure, so an advisory would be in order.

To repair, I would cut out 10mm of the surrounding good metal, and butt weld a small patch in.

Certainly not serious rot.

[Nadir]

Covered by the kick plate, but obvious from underneath the car. Instant MOT failure around here.

[GheeBhow]

Thanks for that - reassuring!

I also meant to ask about the best way of protecting the dip where the outer under sill and the floor edge panel join - you can see the line just below the edge of the boxing panel. I can't really rub it back because it's such a narrow slot. Should I bung some Kurust down it and then overpaint it with Hammerite?? What have other people done?

Ta
Neil

[MoggyTech]

http://www.bilthamber.com/dynaxs50.html

The above cavity protection is currently one of the best available. Best for those hard to reach areas

[GheeBhow]

Oh that's good - I've got some of that! I was planning to spray it over the painted surfaces, but wasn't sure whether to first paint into that join, or leave it unpainted and just stick S50 into it...

Ta
Neil

[bmcecosse]

It WILL need welding - it's quite seriously rotted - and the B post looks like it is rotted too! This should not pass an MOT - it's structurally unsound!

[kennatt]

as bmc says needs welding def mot fail.I would think that if you gave the bit of sill to the outside of that hole a good poke it would also show that a strip will need welding right across the width of the sill f rom the outer edge,and also the bottom of the b post needs repairing,if its not allready holed it soon will be so do it at the same time good luck

[GheeBhow]

From what I can tell - and I've had a good poke about - the B post is solid. There's some surface rust, but only a light bit. I guess the photo makes it look worse than it is. But definitely some welding due before its next MOT I think...

[MoggyTech]

B post does indeed look solid with just surface rust that needs seeing to.
I think the local corrosion on the sill, may be due to the end of the sill kickplate not being sealed correctly where it meets the B post. If it's not sealed, water runs down the door seal, and finds its way into the sill section, rather than run off the kickplate and out onto the road.

I would remove a lot more paint around the damaged area if you haven't already, just to double check how far the rot has spread.

If the hole that can be seen, is indeed the only area of the sill that is effected, then in no way is the cars structure unsafe. Just get a decent patch on there. For a second opinion, you can leave the underseal off for the MOT, so the mechanic can carefully check the area, then underseal after MOT.

[GheeBhow]

Thanks for the advice MoggyTech, you're bang on the money about the kick plate - there's a small gap. I hadn't realised that there was meant to be a seal there. What's generally used - is there a rubber strip, like a door seal?

What do you reckon about preventing rust down the outer under sill / floor edge panel join? Kurust & paint or just Waxoyl / S50?

Thanks,
Neil

[MoggyTech]

Thanks for the advice MoggyTech, you're bang on the money about the kick plate - there's a small gap. I hadn't realised that there was meant to be a seal there. What's generally used - is there a rubber strip, like a door seal?

What do you reckon about preventing rust down the outer under sill / floor edge panel join? Kurust & paint or just Waxoyl / S50?

Thanks,
Neil

Kickplates come off my car every spring to check inner sills, so I just use Dum Dum sealer at the end seams. You can also use the silicon sealant that comes in a tube and fits into one of those syringe type guns.

I use Waxoyl in all box sections. Underneath the car I have removed all of the underseal and replaced with Hammerite #1 Rust Beater Primer, followed by three coats of Smoothrite. I found it difficult to judge what was going on underneath underseal, and often found surface rust under it when scraped off.

Oh and make sure all of the drain holes are clear, in the sills/chassis legs and doors. The restorer slapped plenty seam sealer over his excellent welding, so I haven't had any major rot problems. A large cable tie is great for clearing the drain holes, as it's plastic, it doesn't damage the paint around the drain hole, which can of course cause rust!

[alainmoran]

One thing to remember about the silicone sealant that comes in tubes, is that the plasticiser which keeps it fluid is usually acetic acid ... not good for metalwork ;)

[MoggyTech]

One thing to remember about the silicone sealant that comes in tubes, is that the plasticiser which keeps it fluid is usually acetic acid ... not good for metalwork ;)

Didn't know that! Learn something new everyday, and certainly won't be using sealant again near metal. Dum Dum it is then.

[GheeBhow]

Dum Dum for me too! Thanks for all the advice. I think I know what to do now...

Neil

[bmcecosse]

Better not to make it a 'sealed' box - which will only sweat internally and rot all the more. The gaps at the end let it breathe - don't block them up.

[MoggyTech]

The breathing point for the Kickplates is at the top where it lips over the inner sill edge inside the car. Not trying to step on any toes here, but the sides should be sealed to prevent water from the door seal running into the sill. That's why the designers made the drain holes with a lip that points backwards. In a properly constructed car, water should not get into the sill box section, just water vapour as present in the atmosphere in high humidity conditions. With no seal at the top or bottom edge of the kickplate, there is adequate ventilation to atmosphere to allow the box section to breath.