17 replies to this topic

[vx220]

Hi all,

This is probably too far away for me anyway, but the seller says he intentionally used oversills to avoid rust traps?

EBay #284356845311

Just wondered what people's thoughts were? I'd always thought oversills block the drains?

Thanks in advance...

[surfblue]

They do and they are not ideal however if all the rusty previously fitted sills are removed they are fine. My car is 10 years plus from fitting and they are perfect but the car has only done 4000 miles in that time and not used in winter or wet weather if I can avoid it. I'd like proper sills fitted but it would be spending money that isn't really required.

[mab01uk]

Oversills have no drainage holes which is a problem if you use your Mini often in wet weather, however if it is a sunny weekends only car then you should be fine leaving as is.

Very early 1959/60 Minis had flat outer sills with no external drainage holes but the footwells got wet in rainy weather!

As said ideally the old rusty sills have been cut away before fitting.

[dyshipfakta]

He’s been on the peace pipe. Just means will end up replacing inner sills floors and heal board next time rather then just outer sills.

[nicklouse]

Oversills have no drainage holes which is a problem if you use your Mini often in wet weather, however if it is a sunny weekends only car then you should be fine leaving as is.

Very early 1959/60 Minis had flat outer sills with no external drainage holes but the footwells got wet in rainy weather!

As said ideally the old rusty sills have been cut away before fitting.

Wet floors was to do with the incorrect design of the toe board. The sills used were also foam filled.

 

the issue with oversell is not wet weather but they hold any moisture the runs down from A B C pillars and the rear quarter panels.

[sonikk4]

Its the same old story with these. As mentioned god knows how many time's, they were used as a repair sill, sometimes to hide further rust, bodgery etc.

 

Now yes people have fitted them as a direct replacement with the inner sill being in good condition ( i have in the past but should have known better) but they do not form the correct cross section with regards to strength, they trap moisture and as Nick has alluded to, moisture will drain down from A and B posts. (condensation mainly)

 

Yes you can fill them with a wax based product of your choice BUT if your inner sill is clear of rust then why not fit the correct short sill as it does not need seam welding along the bottom???

[Compdoc]

My car had oversills and looked perfect in their fresh paint. But I decided to remove them anyway!

 

[mab01uk]

The design fault Issigonis made with early Minis was they lapped the joint the wrong way with the outer sill part of the floor and the inner sills as a separate panel and the sills therefore drained inside the car under the carpets, (there is film of Issigonis detailing the lap joint problem) it was not just the toe board joint which was also lapped the wrong way. Prototype testing was done in the warm summer months and failed to show the problem. The early sills were not originally foam filled at the factory, that came in later in production as a stop gap effort to temporarily fix the problem until the re-designed floor and sills got into production. Dealers were also given instructions on sealing various joints in the floor, sills and bulkhead to retrospectively cure the leaks on cars already out in the field. (See BMC documents and diagrams in link below).

 

This is an Extract from my Austin Se7en BMC Dealer manual:-

 

BMC (Morris) Service Memorandum M/639.

"It is well documented that the early Minis suffered badly from water ingress. Service Memo M/639 is concerned exclusively with keeping the water out. You won't believe what lengths the dealers were expected to go to!"

http://mk1-performan...ofing-M-639.pdf

 

mk1 1959/61 floorpan differances

"There were no external flutes until after October 60. The sill and floor was a single pressing. The inner-sills were four separate panels, two behind the crossmember and two in front. They had reliefs where they joined the floor to allow drainage from the sills into the floor well. The foam was factory installed and was a dealership fudge for vehicles prior to the factory fix. The factory added a closing plate in the cross member to stop the whole of the car filling with the muck when they pumped it in. It got every where. I found it way up the A pillars beside the front screen. A nightmare to get rid of but if you don’t before welding you better have a fire extinguisher to hand. The front seam with the bulkhead was reversed to what is normal now on the very early cars in ‘59 but got corrected in the November I believe. Even so there was no upturn on the floor front or back until the third floor revision post October 1960."

http://mk1-forum.net...php?f=3&t=28637

Edited by mab01uk, 17 July 2021 - 04:08 PM.

[Ethel]

Some useful illustrations for you there. They are properly "repair sills". The inner sill is part of the floor pressing, so when they corrode there's nothing to attach the new outer sill to. Repair sills include extra width so they can reach to where the floor isn't corroded. Properly fitted, with all the rot cut out to the new joint, they were ok to extend the life of the car back in the day. Too often they were just clagged on, hiding a whole load of horrors underneath - even if there wasn't much you'd end up with a double skin under the edge of the floor that would wick up the wet and never dry.

It's your call on the relative value against how quickly it'll need replacing. Bad signs would be a lack of a panel join on the inside of the floor where the inner sills have been cut back and, worse, a triple decker rot sandwich under the plastic seam trims because the original sill is still there, in the middle.

[greenwheels]

to get back to the OP's reference to the Mini for sale on ebay - £16000 for a mini with oversills - you got to be joking. It's a bodge, a proper restoration would be as the original design. To me it raises the question of what other bodges there are!

[Shifty]

I don't mind them, I've made a lot of money out of them.  Either by clagging them on for an MOT many years ago or by now removing them and fitting the correct sills.  

 

They are still a cheap way of getting another years MOT of a ropey car.

 

Fitting them to a car and them asking £15k+ is just ridiculous though, the avoiding rust trap is just nonsense and shows a complete lack of knowledge on the sellers part.

 

It's not a car I'd be considering and even at a much reduced price I'd be looking very hard at the resto quality.

[InnoCooperExport]

Fitting oversills to avoid rust reminds me of a Healey a friend of mine got in for repairs. Initially he'd got it in for an MOT but he refused to drive it to the testing station.

 

The sills hadn't been welded in but fitted with nuts and bolts "as this made it easier to change them when they inevitably got rusty" - according to the owner! Friend told him it was deathtrap and refused to have anything to do with it unless the owner was willing to pay for the necessary repairs. When he got into it half the chassis bars round the rear end were going and the rear leaf spring mounts were basically papier-mâché. What's scary is that the MOT was up for renewal and had been like this for some time... How it was never flagged before is beyond me. 

[DomCr250]

to get back to the OP's reference to the Mini for sale on ebay - £16000 for a mini with oversills - you got to be joking. It's a bodge, a proper restoration would be as the original design. To me it raises the question of what other bodges there are!

Just look at the pics of the engine bay and the underside - you'd expect it to be almost perfect for that type of money.

 

Then there is the way they have lifted it on the 2 post ramp -  'a time served coach builder and panel beater' I'd have thought should know a little better... 

[myredmini]

Nowhere near a 16k car! scabby rust underneath and tatty engine bay, i'd run from that at that money!

[Chris1275gt]

This post had me panicking a bit as I didn't realise mine had oversills I've seen all the horrendous pic on google so I bought a cheap 5.5 mm endescope to nervously check it out. I removed the bottom subframe mounting bolt and slid it in. It appears clean as a whistle with no signs of the original left in there, 1 small 100mm of surface rust on the seam where the b post is which you can just notice on the outside. Poked it down the A pillar to the bottom and all clean also it has vent holes all along the panel at the top of each of the bulges that communicate with the bottom of the void. Previous owner had stored I for 10 years in a dry garage and I never take the Duchess out when it's cats and dogs out side I drive it all year round so I'm happy to leave be.