Oil leaks - how much is too much?

Post by **Geraldine** » Tue Aug 11, 2009 3:51 pm

I seem to be leaking a bit of oil in 2 places, put some cardboard under the car to check how much I'm losing in a day. Seems to be just under 5ml of black oil near the front of the car and a bit more of lighter coloured oil in the middle. I know most old engines lose a bit, but wondered if this was OK?

Post by **8009STEVE** » Tue Aug 11, 2009 3:56 pm

black oil near the front of the car

Engine oil?

of lighter coloured oil in the middle

Gearbox?
Check both levels, engine daily, g/box weekly and see how much you use in a week.

Post by **Declan_Burns** » Tue Aug 11, 2009 7:16 pm

Try if you can arrange it, running the engine with the car over a pit, having cleaned off all the oil and muck underneath beforehand. This will help to locate the actual source of your oil leak(s). I would consider 5ml as a bit too much especially if it's after every trip. You might be lucky and it's only the engine or gearbox drain plugs or both. Could also be the filler cap on the gearbox or where the speedo cable is fitted. I had leaks at all of these points and there are many other sources. Check the engine breathers are working as discussed here so often.

Post by **bmcecosse** » Tue Aug 11, 2009 9:19 pm

Yes - if the breathers are choked even a good condition engine will leak. It needs a slight vacuum to be pulled by one of the breathers being connected to the inlet system. Early cars had this into the air filter casing - which simply spread oil over the paper filter! later cars have a much better system where the breather is connected to a brass inlet tube on the side of the carb. This works beautifully - and eliminates most leaks unless the engine is in really poor condition. Start by checking your breather hose(s) is not blocked.

Post by **les** » Tue Aug 11, 2009 10:06 pm

Minors tend to leak oil, the gearbox/ prop junction and timing cover are favourites, but remember, they are not German cars!

Post by **mike.perry** » Tue Aug 11, 2009 11:28 pm

It's called chassis lubrication. It stops the bottom of the car from rusting!!!!!

Post by **d_harris** » Wed Aug 12, 2009 1:02 am

.... From the outside

Post by **Declan_Burns** » Wed Aug 12, 2009 6:42 am

les wrote:Minors tend to leak oil, the gearbox/ prop junction and timing cover are favourites, but remember, they are not German cars!

Les, Try working on old Porsches and you'll soon give up on the idea that German cars don't leak!

Post by **David53** » Wed Aug 12, 2009 11:48 am

Geraldine the A series engine leaks, even when it has been rebuilt. Mine is only a few hundred miles old and already I have some drips from the front oil seal in the timing cover. Mine is an early car so has the particularly useless felt oil seal.

I have exactly the same pattern as you on my drip tray - A smallish black blob from the front timing cover and a small clear brown drop further back from the gearbox. Unless you have big puddles I wouldn't get too concerned.

Post by **David53** » Wed Aug 12, 2009 11:51 am

bmcecosse wrote:Yes - if the breathers are choked even a good condition engine will leak. It needs a slight vacuum to be pulled by one of the breathers being connected to the inlet system. Early cars had this into the air filter casing - which simply spread oil over the paper filter! later cars have a much better system where the breather is connected to a brass inlet tube on the side of the carb.

What about Oil Bath air cleaners - what's your thoughts on those? My breather pipe runs straight from the rocker cover into the oil bath cleaner.

Post by **les** » Wed Aug 12, 2009 9:30 pm

Les, Try working on old Porsches and you'll soon give up on the idea that German cars don't leak!

I have, you must have found some that have been abused!

Post by **bmcecosse** » Wed Aug 12, 2009 9:45 pm

David53 -as long as it's getting some suction and the pipe is clear it will be fine. At least the fumes/oil vapour won't do the oil bath cleaner any harm.

Post by **alainmoran** » Wed Aug 12, 2009 10:17 pm

A wise man once told me that if you replace your gearbox oil seal, and it goes again within a month or so, then the output bearings in the gearbox are stuffed and allowing the driven shaft to vibrate, destroying the oil seal from the inside.

As for loosing oil, I see it as a 'healthy througput' .. your oil never gets old since you have to top it up so often, and the oil that gets sprayed under the car can only be a good thing (that's actually how my grandad used to preserve the floor of his cars - he would paint it with old engine oil every six months ... now that my minor is back on the road I will be doing the same)

Post by **les** » Wed Aug 12, 2009 10:32 pm

The oil slick running down the drive is a drawback though!!

Post by **Declan_Burns** » Thu Aug 13, 2009 7:06 am

les wrote:
Les, Try working on old Porsches and you'll soon give up on the idea that German cars don't leak!
I have, you must have found some that have been abused!

Abused, no and certainly not by me. You seem to have a problem with Germans. I'm only trying to help Geraldine solve her oil leak problem. Mine leaked like hell when I got it and now it's down to a few blobs just as David mentioned above. I just think 5ml is too much and would recommend sourcing the leak(s).
BTW I'm not German!

Post by **rayofleamington** » Thu Aug 13, 2009 3:50 pm

but remember, they are not German cars!

you mean that we can admit they leak? Saves having to 'pretend' otherwise like many 911 owners!!

Post by **les** » Thu Aug 13, 2009 9:59 pm

You seem to have a problem with Germans.

Problem? I thought my view of oil tightness would be seen as a complement.
BTW I won't mention the war!

Post by **bmcecosse** » Thu Aug 13, 2009 10:26 pm

Yes - I saw it as a 'complement' too les!

Post by **Declan_Burns** » Fri Aug 14, 2009 6:38 am

Les,
Compliments always welcome-perhaps I took you up wrong and took offence-no probs!