G'day

Can anyone recommend a diesel mechanic that works around the Harbour for some advice/service/repair re an old BUKH DV8 8hp, single cylinder diesel ?

The few people Ive tried so far have been at worst shonks, and at best just not particularly interested (for various reasons).

Any suggestions ?

Cheers.

Lots of 'little' things.....

Significant blue smoke (but only intermittently ?)
Difficulty starting (it takes 10 seconds of cranking when it used to take 2)
Sluggish throttle response
Panel lights (amps, oil, temp) and buzzer alarm need testing/fixing
Pressure coming from oil filler (from crank case ? how much is normal ??)

The engine is old but only about 30 hrs out of a full rebuild. The first 25hrs were faultless..... the smoke, starting and throttle problem have just suddenly presented themselves.

My main problem has been finding someone interested in working on a oldish engine, ideally, where she lays on the harbour.

Any suggestions would be most welcome....

Cheers,
Craig

SumFingWong said...

Lots of 'little' things.....

Significant blue smoke (but only intermittently ?)
Difficulty starting (it takes 10 seconds of cranking when it used to take 2)
Sluggish throttle response
Panel lights (amps, oil, temp) and buzzer alarm need testing/fixing
Pressure coming from oil filler (from crank case ? how much is normal ??)

The engine is old but only about 30 hrs out of a full rebuild. The first 25hrs were faultless..... the smoke, starting and throttle problem have just suddenly presented themselves.

My main problem has been finding someone interested in working on a oldish engine, ideally, where she lays on the harbour.

Any suggestions would be most welcome....

Cheers,
Craig

From an armchair perspective it sounds like the rings have not bedded correctly or suddenly stuck, blue smoke/too much crankcase compression/hard starting.

Hopefully after the rebuild a suitable oil was used in the crank case. Steer clear of modern oils. Modern oils are the worst thing you can do to a diesel.

Check out the pommie forum and inquire there; forums.ybw.com/index.php?forums/practical-boat-owners-reader-to-reader.13/

Lots of Bukh enthusiasts there.

I'm not a diesel mechanic but might be able to help. Send me a message.
Cheers
John

SumFingWong said...

Lots of 'little' things.....

Significant blue smoke (but only intermittently ?)
Difficulty starting (it takes 10 seconds of cranking when it used to take 2)
Sluggish throttle response
Panel lights (amps, oil, temp) and buzzer alarm need testing/fixing
Pressure coming from oil filler (from crank case ? how much is normal ??)

The engine is old but only about 30 hrs out of a full rebuild. The first 25hrs were faultless..... the smoke, starting and throttle problem have just suddenly presented themselves.

Craig,
These are classic symptoms of a glazed bore. Quite common and is caused by using too good an oil and running the engine at low revs or idle with no load. The piston rings stick in and the bores get a glaze which stops the crankcase oil sticking to it. Suddenly you have low compression, lots of crankcase blow by up the oil filler pipe, blue smoke and increased oil consumption. Because of the lower compression the engine is harder to start. People charging their batteries by running their propulsion engines in neutral at the mooring or anchor for an hour or so are asking for glazed bores.
Now bearing in mind my comment above about an armchair expert and the advice you get is worth what you paid for, there are plenty of fixes.
There is a product advertised in Trading Boat, the name escapes me and I don't have a copy. The add reads something like "need an engine rebuild but can't afford it". This is a snake oil that actually works well. Made in Queensland and costs about $80 for the small bottle. Its a foul smelling yellow mixture that stains badly. Mix it in your diesel using the ratios recommended. Take your yacht for a motor around the harbour at normal revs, about 80% throttle. The main engine in my fishing vessel was using 2 to 3 litres of oil a day. One dose of this stuff and in less than 3 hours was reduced to almost zero. Seems expensive snake oil but probably what a diesel mechanic charges for one hour!
There are other methods too that require getting your hands dirty and I have no experience of.

Thanks for all the replies....

For info, after rebuild I have run the engine pretty hard for the first 25 hrs (80odd percent). The only exception to this is a few mins at idle to warm up and cool down - problem ?

Just to bump this back to the top again - can anyone recommend a diesel mechanic around Sydney Harbour ? Ideally one thats in the east or mobile ? (It seems noone wants to work on small old diesels any more !!)

Thanks.