ADVISORIES The regulators of the mot system should have a serious look at the way MOT stations report minor problems, I won't say" faults" are reported. They appear to me just a way of garages to increase their income at the expense of the unwary or customers completely ignorant of how a car works. The OPs sump being a typical example. Another would be our 2015 A1. Same MOT station first year N/S drive shaft boot slightly leaking, 2nd year ditto, December now NO advisories. The leak miraculously fixed itself. Err no there is still a slight weep on one of the securing straps. How many are shelling out good money to fix minor problems. OK you could argue that some problems may get worse but many won't. A pass is a pass not an invitation to part with your money.

Just had an MOT on my Nissan Note. It's come back with an advisory (amongst others) stating 'oil leak, not excessive; sump porous and corroded'.

I've heard this word 'porous' used to describe a metal part, and I still can't imagine metal letting oil through like blotting paper or a filter - which has pores. I assume the tester noticed an oil seep which he couldn't locate.

Rust is porous. If it rusted in from the outside, it would eventually reach the inside, and then it would seep oil.

It wouldn't quite be a hole, but it might be weakened over a hole sized area, and later become one.

Its never happened to me, probably because my sumps are usually oily enough to prevent rusting, but I can imagine it happening. According to the Internyet, it seems to happen to Americans.

And Fiat Panda's, apparently. There's a surprise.

www.fiatforum.com/panda-iii/453852-sump-pan-rusted...l

And Punto's, and Fiestas, and,,,

www.honestjohn.co.uk/forum/post/index.htm?t=37209

If I had a rusty sump I'd treat it with sunflower oil and rub with aluminium, probably just by hand using foil rather than a can disk in a drill, in case it was significantly weakened.

When I read of such failures I think of doing that, then I go and look at my sump, which is a thin steel pressing, and it isn't rusty, so I don't bother.

I suppose I'll go and do that again.

Again

www.honestjohn.co.uk/forum/post/index.htm?t=96864

I should have just done it when I had the sump off, but it wasn't a priority.

Edited by edlithgow on 19/12/2020 at 06:29

Yeah, that's the impression it gave me..

Don't know that info unfortunately, although I read that older models generally have steel.

If there's no oil on the ground the sump cannot possibly have a hole in it - unless it's empty! It probably looks a bit rusty and possibly slightly weepy at the front and/or back. Just paint the rusty area with old engine oil. The MoT threshold for a fluid leak failure is a puddle 75mm in diameter within five minutes, engine running.

Just for info, while driving home from Zambia nearly 50yrs ago we put a tiny hole in the sump (old Toyota Crown, couldn't afford a reliable 4x4) on a rocky bit of the sahara desert. Permanently repaired by hammering in a sharpened matchstick and sealing with araldite.