Oil weep from sump extraction pump

[MartynMacc]

Can anyone help.....

I have noticed a small amount of oil which appears to be coming up the stem of my oil extraction pump on my Barrus Shire 45 (year 2000). It has only recently started doing this, I have checked the O ring which looks okay was wondering if something could cause the oil to pass the ball bearing type of non return valve at the bottom of the stem

Thanks

 

[ditchcrawler]

Some engines have an isolation valve between the pump and the sump, but I would have thought that the oil is supposed to go in that direction through the check valve. Any pressure in the sump will push oil up there

[MartynMacc]

Thanks Brian, 

I agree with your logic, just seems strange that it has just started to happen after 20 years, I have had the boat from new.

There isn’t an isolation valve between pump and sump on this engine.

Martyn

[David Mack]

Perhaps after 20 years wear you're getting some blow by past the piston rings, which is pressurising the sump.

[MartynMacc]

Thanks David,

Yep that’s a possibility, however I apologies for not adding that even though it is 20 years old it has only done 4000 hours.

[Tony Brooks]

Try running with the oil filler cap off, if the oil weep stops then it is crankcase pressure so its time to check the crank case breather system for blockages. Maybe check the breather system anyway.  If the breather is clear I would fit a valve onto the base of the pump.

 

The pressure only needs to lift two small balls off the seats a tad to allow oil mist to be blown into the pump body.

Edited August 7, 2020 by Tony Brooks

[MartynMacc]

Thanks Tony,

I’ll give that a try this coming week.

Many thanks

Martyn

[Nightwatch]

My name is Martyn with a ‘Y’. I also have a Barrus Shire engine. Its now 18 years young. And, ihave also notice over the past fewweeks I’m having to wipe oil of the top of the extraction pump.

 

Odd world isnt it? Thanks for raising this issue. I had put it down to being on the Thames and higher revs.

[Tony Brooks]

Just now, Nightwatch said:

My name is Martyn with a ‘Y’. I also have a Barrus Shire engine. Its now 18 years young. And, ihave also notice over the past fewweeks I’m having to wipe oil of the top of the extraction pump.

 

Odd world isnt it? Thanks for raising this issue. I had put it down to being on the Thames and higher revs.

It may well be because the higher the revs the more load on the engine so the more gasses that bypass the pistons.

[Nightwatch]

Will see how it behaves when we get back onto the canals. Thank you Tony.

 

Lets just say, the engine is overdue an oil change, so, maybe new oil might help a little. Its high on my list of ‘things to do.’

Edited August 9, 2020 by Nightwatch