Old engine oil leak - Acceptable or Unacceptable?

Tim Good

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Ok so my engine is 22 years old but going strong still. However, there is a slightly oil leak from somewhere near the base of the engine leaving a little oil in the bilge. Its small enough that my oil level doesn't appear to go down on my dip stick. There is little or no access to that part of the engine for me to pin point it. Would you say this is:

A: Perfectly acceptable for an engine of that age. Just keep an eye on things and do the usual maintenance .

B: Unacceptable. Strip everything back and have it lifted so you can see whats going on.
 
If the oil level stays the same and therefore the oil drop is negligible, it doesn't matter. The engine may go on without any issues for another 22 years. keep and eye on the oil dipstick to make sure that it doesn't get any worse. If the oil leak becomes nuisance then you can take a view; in the meantime there is no problem.
 
Depends where the leaked oil is going: if into the main bilge it's a major mess and if you pump out any bilgewater it's going to be oily. On my boat a much newer engine leaks oil a bit but it is always fully contained in a smooth moulded-in GRP drip-tray. Would very much like to fix leak but it means lifting engine, so for now I'll just mop up oil occasionally.
 
Depends where the leaked oil is going: ...

It also depends on where it's coming from. Slow drip from a damaged rocker cover gasket? Meh. Slow drip from one of those 1GM10 steel oil pipes? Danger, WIll Robinson, danger. Until the OP knows the source, it's not safe to ignore.
 
Depends where the leaked oil is going: if into the main bilge it's a major mess and if you pump out any bilgewater it's going to be oily.

This can be minimised by rolling up some polypropylene oil absorbent sheets into a "sausage" and floating it in the bilge.
 
Ok so my engine is 22 years old but going strong still. However, there is a slightly oil leak from somewhere near the base of the engine leaving a little oil in the bilge. Its small enough that my oil level doesn't appear to go down on my dip stick. There is little or no access to that part of the engine for me to pin point it. Would you say this is:

A: Perfectly acceptable for an engine of that age. Just keep an eye on things and do the usual maintenance .

B: Unacceptable. Strip everything back and have it lifted so you can see whats going on.

I reckon A. But I would want to know where it is coming from, so I'd fiddle around with a mirror and torch or an inspection camera of some sort and try to locate the source?
 
Both options work. Its all personal preference, providing you can ascertain its not anything serious.

Is it worth the effort of fixing in order to have clean bilge?

Might be worth cleaning it and using an extendable mirror to try and see where its coming from.
 
If the oil level on the dipstick does not go down, could the leak be from the gearbox? What does the oil smell like? I find that measuring the gearbox oil level is less precise than the engine because of the screwing/unscrewing/resting/not resting routine.

Richard
 
Second the advice to find out what it is and keep the oil out of the main bilge.

Our much newer engine has a small leak through the rear crankshaft seal, which is not going to do it any harm, and the oil all goes into the fibreglass tray formed by the saildrive mount. None escapes into the bilge even in quite rough conditions.

Mopping it up periodically is a bit of a chore, so one day I will fix it (or rather, we've agreed that I'll get the engine out and my dad will fix it :) ) but it might be another year or two before that happens. If I didn't mind cleaning up then it could go on indefinitely.

Pete
 
snipped ....
Our much newer engine has a small leak through the rear crankshaft seal, which is not going to do it any harm, and the oil all goes into the fibreglass tray formed by the saildrive mount. None escapes into the bilge even in quite rough conditions.
Pete

Not a Yanmar is it? My leak is also rear crankshaft seal.....
 
We mustn't pollute. Buy a bail of cheap child nappies. They will soak up oil before it trickles to bilge. Then dispose responsibly.

Nappies will soak oil and water up, so if the bilge isn't 100% dry you get through a lot of nappies. The proper oil absorbent sheets/sausages only soak the oil up, leaving the water for the bilge pump to deal with.
 
You need to find out where the leak is coming from. Clean the engine thoroughly. If you spend less than 3 Hours cleaning it then you have not cleaned it properly. Observe where you have the leaks, take photos, and report back.
 
You need to find out where the leak is coming from.

As the owner of an old hydraulic Citroën, I am well versed in oil leaks. The golden rule I learned with the DS is "Never decide to ignore a leak until you know exactly where it is coming from." I developed this theory after deciding that I could safely ignore a slow drip from somewhere at the front of the engine, only to lose a full gallon of hydraulic fluid (ie all of it) in two minutes when a pinhole opened up. On the bright side, the spray of oil kept the front half of the car protected from rust for years, but as the blow-out happened in rain at 10pm on the M6, I could have done without it.
 
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As the owner of an old hydraulic Citroën, I am well versed in oil leaks. The golden rule I learned with the DS is "Never decide to ignore a leak until you know exactly where it is coming from." I developed this theory after deciding that I could safely ignore a slow drip from somewhere at the front of the engine, only to lose a full gallon of hydraulic fluid (ie all of it) in two minutes when a pinhole opened up. On the bright side, the spray of oil kept the front half of the car protected from rust for years, but as the blow-out happened in rain at 10pm on the M6, I could have done without it.

The Amoco Cadiz was wrecked for a similar reason. There had been a leak of hydraulic oil from the steering system for some time but it increased severely over a short time. Then they discovered they had no spare oil.....

My ex-boss was on the investigation team.
 
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