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rounded sump plug !! - Andrew
Today I decided to change the oil and filter on my 1.8 escort diesel, until i tried to undo the sump plug ! try as i might i could not undo it. The trouble was that the plug itself had its corners rounded, making the spanner slip. Help !!!

Is there another way I could undo the plug ? Or is this now best left to a garage to help !!

many thanks, Andrew
Re: rounded sump plug !! - ian (cape town)
Mole grips, and then fit a new plug?
Re: rounded sump plug !! - Mark (Brazil)
weld another nut on top of it.


Whack it with a chisel just to crack it free and then use molegrips.

Did you round it (suggesting it is *really* siezed) or was it already rounded ?
Re: rounded sump plug !! - steve paterson
Dead easy to round off Ford sump plugs unless you use a 13mm single hex. socket. A single hex 1/2" socket is a bit smaller, you might be able to hammer one on. If it's completely rounded try a pair of stillsons on the shoulder part of the plug, it usually works. (you'll see what I mean if you look at the new plug). Hammer and chisel is the next step, again on the shoulder part.
Re: rounded sump plug !! - David W

Steve is right, get a new plug and use stillsons on the larger shoulder bit. Stillsons are often better than mole grips for this. Chisel alo works on the shoulder.

Halfords keep popular sump plugs.

Re: rounded sump plug !! - Mike H
I've managed to do the same on my Saab. I have decided to bite the bullet & rather than make things worse, let them sort it out - at the end of the day, if you chew it up badly & you can't sort it, it will then be more difficult (therefore more expensive) when a garage has to eventually sort it!. I suspect that it is the sort of job that will be very easy if you are standing upright with the car above you on a hydraulic hoist. I have already bought the plug & asked the local garage to do it (much cheaper than the £70 per hour +VAT charged by the local Saab dealer), but for various reasons they never got round to it. My mistake was not being able to get right under it in the first place, if I could have done I could have got the socket square on straight away.
Re: rounded sump plug !! - Alwyn
Be careful if you use brute force. I tried this with a Cortina sump plug and ended up by cracking the brazing/welding around the female thread housing.

New sump was fitted to cure it. Oh dear.
Re: rounded sump plug !! - Rob F
Give it a good blast with a blowtorch before you undo it. Careful though!

Rob F
Re: rounded sump plug !! - Dave N
Suck the oil out.
Re: rounded sump plug !! - J.Bonington Jagworth
When I last bought an oil filter, I was recommended (by VAG garage) to buy another sump plug as a matter of course! I compromised and just bought the copper washer, but it makes you wonder what the garage normally does to them (probably with an air tool set to do up wheel nuts)...
Re: rounded sump plug !! - steve paterson
The Ford Duratorque engine (as fitted to a Transit) has a sump plug with about 2 pence worth 'O' ring as a seal. Easy enough to remove and replace the ring, but it isn't available as a 'part'. Comes complete with sump plug at about £3
Re: rounded sump plug !! - j.cronin
And it's still about £50 cheaper than anyother supplier!!!
Re: rounded sump plug !! - Brian
I change the oil on my motorbike between services and have never replaced the washer, although I always make sure that the sump bolt, washer and seating are free of dirt before replacing.

I only do them up "firm hand tight" and have never had one slacken off in use, let alone leak.

After all, they take absolutely no strain in use, there seems to be no need to torque them up and once they grip they should stay in situ forever. Or am I being simplistic?
Re: rounded sump plug !! - Mark (Brazil)
>>I was recommended (by VAG garage) to buy another sump plug as a matter of course!

Pontiac absolutely insist on replacing the sump plug on my Firehawk everytime they change the oil - although that isn't very often since I am rarely at our place in SF so it doesn't get driven much.

They explain that the price of a plug is nothing - the pricing of digging out a dead one is high.
Re: rounded sump plug !! - Mike Harvey
I find most sump plugs and oil filters for that matter overtightened by some gorilla with the attitude that "as its oil, its crucial, and I'll give it some extra to be sure". It does more harm than good. Torque it up, Brian is right, it will not come undone.

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