Paguro / Farymann generator keeps dumping all its engine oil

[Ashman]

My two year old (800 hour) single cylinder Farymann powered Paguro generator has started dumping all its engine oil due to excessive crankcase pressure and I can’t find a solution. Crankcase pressure builds to the point that the firmly seated dipstick blows out and oil forces its way past the crankshaft seal! Valves and springs appear to be in good condition and I have changed the piston rings but to no avail. I’ve checked the tappet clearance both hot and cold and they are always ok. I have now replaced the decompression device and all was well for three hours then bingo without warning it dumped all the oil again.

The UK dealer has told me to find a diesel fitter to look at it but here in Central America, where we are liveaboards, it is virtually impossible to find a decent mechanic let alone one with any diesel engine skills (for instance - not having a valve spring compressor I took the cylinder head to a local ‘expert’ to remove the valves……he produced a hammer and socket and was going to bash and bounce the collets out until I suggested I would prefer to find a gentler engineered solution).

We use the generator to power our 75lph watermaker and charge the batteries so life at anchor without it is now restricted, less showers, restricted cruising range etc……I am thinking that we should sail to the US and convert the water maker to be driven by the boat engine or perhaps I should buy a second alternator and go 12v instead……but having so much money invested in the Paguro and with recent costly purchases of spare parts I feel that I’ve got to find a solution to the excessive oil pressure first….so has anyone experienced a similar problem and maybe got a possible solution?

 

[VicS]

Crankcase breather blocked or valve therein stuck ??????

Try Googling
see:
http://www.ybw.com/forums/showthread.php?236791-farymann-diesels-powered-generator
to get you started

 

[RichardS]

Crankcase breather blocked or valve therein stuck ??????

Try Googling
see:
http://www.ybw.com/forums/showthread.php?236791-farymann-diesels-powered-generator
to get you started

Vic's suggestion sounds very likely bearing in mind all the work you've done.

What happens if you run the engine with the oil filler cap off. Have a cloth over it at first just in case there is a lot of oil spray but then slowly remove the cloth. If smoke pours out and blasts oil everywhere then there is probably a serious blowby issue. If you get a fairly mild pulsing and just a bit of oil splatter and no fumes then Vic is right.

Richard

 

[bigwow]

I found this company very helpful when I rebuilt my genny.
http://www.dieselpower.co.uk/

 

[Ashman]

In response to Vic's suggestion I also was concerned about the little pea valve that serves as a crankcase breather. So the the earlier posts are very interesting. Unfortunately it is impossible to remove the pea valve from the cylinder head easily .......I've tried but it appears to be friction 'welded' in. The UK dealer says that they have never head of a problem with one of these valves and so I cleaned it up by flushing it through when I had the head off...... it is a very simple device, basically a plastic pea in a steel tube. I am still very suspicious of it but to replace it will involve an engineering shop to draw it out but I might be doing that way when I get to the US.
In reply to RichardS helpful suggestion the strange part is that I have run the engine for several hours whilst checking the crankcase pressure at intervals using the filler cap without seeing any overpressure......then suddenly pressure will build for no apparent reason and oil blows out. I can't understand where the blow by comes from as I have replaced the piston rings and checked that the valves are seating and operating properly......I did check that it wasn't a valve sticking issue.
After the engine has overpressured the inlet valve tract is full of oil suggesting it is being pump past the crankcase breather pea valve but I don't see how that can happen?

Thank you for your suggestions, I appreciate your help.

 

[Tradewinds]

In response to Vic's suggestion I also was concerned about the little pea valve that serves as a crankcase breather. So the the earlier posts are very interesting. Unfortunately it is impossible to remove the pea valve from the cylinder head easily .......I've tried but it appears to be friction 'welded' in. The UK dealer says that they have never head of a problem with one of these valves and so I cleaned it up by flushing it through when I had the head off...... it is a very simple device, basically a plastic pea in a steel tube. I am still very suspicious of it but to replace it will involve an engineering shop to draw it out but I might be doing that way when I get to the US

I wasn't going to respond as my problems (exactly as yours) were with a new FP4000 (Farymann engine) way back in 1993.

After many unsuccessful attempts to solve my same problem (last time by an engineer) I ended up phoning FP in Germany from the Caribbean.

They said - what colour 'pea' is in the 'valve'. So I said white. No, it should be red (or some such) - it's the wrong material and it deforms and gets stuck. We'll send you the correct one. And they did and thereafter no more problems with oil spewing out.

As I remember, the valve is a press fit and it was a case of levering it out (probably using molegrips), changing the pea and pressing back in (probably with a hammer!).

Anyhow, it was a waste of time because the FP4000 succumbed to another more terminal problem. I gave it away in NZ for a pittance. Good riddance - no longer did I have to wait in exotic ports for expensive parts for that pile of S**t.

It was like having a boil lanced.

Hope this helps.

 

[RichardS]

In response to Vic's suggestion I also was concerned about the little pea valve that serves as a crankcase breather. So the the earlier posts are very interesting. Unfortunately it is impossible to remove the pea valve from the cylinder head easily .......I've tried but it appears to be friction 'welded' in. The UK dealer says that they have never head of a problem with one of these valves and so I cleaned it up by flushing it through when I had the head off...... it is a very simple device, basically a plastic pea in a steel tube. I am still very suspicious of it but to replace it will involve an engineering shop to draw it out but I might be doing that way when I get to the US.
In reply to RichardS helpful suggestion the strange part is that I have run the engine for several hours whilst checking the crankcase pressure at intervals using the filler cap without seeing any overpressure......then suddenly pressure will build for no apparent reason and oil blows out. I can't understand where the blow by comes from as I have replaced the piston rings and checked that the valves are seating and operating properly......I did check that it wasn't a valve sticking issue.
After the engine has overpressured the inlet valve tract is full of oil suggesting it is being pump past the crankcase breather pea valve but I don't see how that can happen?

Thank you for your suggestions, I appreciate your help.

From what you say, it does sound like an intermittent problem with the breather, something like Tradewinds suggest. You could check this 100% by leaving the oil filler cap off and rigging-up a piece of hose vertically to form an oil trap and then curving over into an old plastic bottle. In the old days lots of cars had similar devices before they started re-cycling the pressure into the inlet. You'll probably need some gaffer tape but it should be possible to run the engine for weeks with such a contraption. If you have no more oil dumping you know where the problem lies.

Richard

 

[superheat6k]

I would also suggest checking the seals on the exhaust valve stem. The exhaust valve is prone to corrosion from salty exhaust gases, which makes starting difficult if the seat becomes worn or rusty / pitted, but if the valve stem were rusty this could allow hot exhaust gases to blow by and down into the sump.

I would also check you do not have any restrictions on the exhaust outlet, e.g barnacles, etc on the skin fitting, as this could also cause excess pressure to build up inside the crankcase.

The website provided earlier will sell Farymann parts at a fraction of the cost from marine diesel firms www.dieselpower.co.uk (Mitcham Diesels).

I have the parts list somewhere so PM me if you need it.