Irish Mini Owners Club

i just had my engine rebuilt i have done 500 miles sofare on it i havent let the revs go over 3500 rpm and fastest i have driven it was 60 mph havent driven it much in the last 2 weeks and to my saprise when i went to take it out yesterday the was a small puddel of oil on the ground under the engine cant see it dripping from anywhere but am worried now any ideas any one

Oil leaks in a mini are very common, it takes great skill and luck to get a perfectly sealed mini engine, first off make sure the correct weight oil was used; 20w50 should be used but most mechanics forget about the gearbox and use 10w40 which is to thin and can damage the gearbox. Secondly jack up the car and have a look, there is really only 3 places that minis leak, No.1 is the output shaft seals (inner CV joint) at the gearbox (either side) No.2 the rod change seal (where the gearlever enters the gearbox) No.3 the rocker cover gasket (top of engine). All can be fixed with new seals/gaskets so not to worry if it is one of these. The only other seal that could leak is the crankshaft damper seal (next to the radiator). Hopefully it is one of these.

As GTM c oupe said......most Minis leak oil. I had the rod change seal changed for a new one.....thought of putting in two but THOMAS was fitting it for me and we had very little room to work under it. Still have a leak now but its more than likely the output shaft seals.

Check everywhere GTM said and dont worry too much......nothing that cant be fixed

With the rod seal one, sometimes the casing can be damaged by people trying to pull the seal out, its a bit tricky to get out. If the casing is damaged, no seal will work

My seal was in for 14 years.....came out fine....getting a new one back in was a different story.

im going to bring it back to the lad who rebuilt it for me i will only make a arse of it if i start messing about was worried it was the head gasket

GTM Coupe wrote:first off make sure the correct weight oil was used; 20w50 should be used but most mechanics forget about the gearbox and use 10w40 which is to thin and can damage the gearbox.

Interesting you should say to use 20w50, I just did a change yesterday but used 10w40 because that's what was the Haynes manual said and the Mini manuals say 10w30....suffice to say I'm a bit confused.

J145 wrote:

GTM Coupe wrote:first off make sure the correct weight oil was used; 20w50 should be used but most mechanics forget about the gearbox and use 10w40 which is to thin and can damage the gearbox.

Interesting you should say to use 20w50, I just did a change yesterday but used 10w40 because that's what was the Haynes manual said and the Mini manuals say 10w30....suffice to say I'm a bit confused.

20w50 is the preferred choice for older high mileage enigines and boxes.....10w30 is whats used in them when new......and th Haynes manual can be taken with a pinch of salt sometimes. Dont think it will adversely effect the car but would need more frequent changing.

20w50 has always worked for me. http://www.ime.org.uk/ime/o/oil_info.html

Ok then I think I'm grand, mine has only 28k on it and I'm in the habit of changing the oil in all my cars at about the 3/4k mark

20w/50 is the only oil to use in road going manual minis.I always used Duckhams but they have discontinued it due to falling sales.There are a few smaller companies who operate in niche markets starting to make it again,Comma,Millers,Morris and Halfords still stock it.Rover specifed 15w/40 for later cars but alot of these suffer from premature gearbox wear.If you have an automatic then 15w/40 is the best oil to use and both types should be mineral only.

one other place they can leak from is the sump bung,
if anyone has been near the gearbox (ie, taken the selector fork out) they may have forgotten to replace the rubber ring washer on refitting