Bukh - experience with the charging system anyone??

[Durcott]

Hi Folks - 2014 finds me with a new boat - and inevitably a new set of problems. (sorry - opportunities.)

We have a mid '80s Bukh 20, which seems to run quite nicely, and may even have been well maintained.

I've only fired it up a couple of times while I work the boat up for its trip home. It doesn't start on 'first spin' and it ticks over a bit fast, but apart from that, it seems smooth.

I've noticed there is around 15.5 Volts on the battery while the engine is running. It's quite variable either side of this, but not to an alarming level.

However, on the motor control panel, I get a flickering red 'Charge' light, and a very brief 'chirp' from an alarm every few seconds.

There's a reasonable flow of cooling water, and the engine's not been running long enough to get too hot.

Does anyone have an opinion on why the charging light would be active, and what is triggering the alarm chirp?

The alternator looks like it's probably original, but the presence of decent volts makes me suspect it's the monitoring system that's playing up, not the alternator.

That said, I'll probably whip out the alternator anyway - make sure the internals are OK.


Also - while I'm here - there is a red, blue and white indicator on the panel. The legend has gone from the white indicator. Does anone know what it indicates?


And finally, I've done a trawl through the forum on Bukh - folk seem to be generally happy with them. Is there anything to look out for, or a top tip for a 'must do' maintenance activity (I mean apart from oil change / anode change (thanks Cliff) / filter change and keep an eye open for low water flow)? I know the engine has been looked at recently, but I'd like to get a feel for any warning signs that I can look out for myself.

Jeff

 

[bert49uk]

The instrument panel for the Bukh is not the best design, you may not have a problem at all but I would check through the charging system just for piece of mind

 

[robmcg]

Simple things first, how is the belt tension and have the teeth on the belt worn so it is slipping a bit. I once replaced an alternator that turned out to just have a slipping belt, even though it wasn't really visible to the naked eye or ear!

 

[chewi]

Does it have a diode splitter added for charging two batteries?

I added one to mine (DV10) but I had to remove it because the alarm chirped annoyingly in normal running.

 

[stevd]

15.5 volts seems a little high to me. Shouldn't it be around the 14 - 14.6 volt mark when charging?

Also, the bukh do sound like they are idling quickly. You can buy on ebay a hand held tachometer for under a tenner if you are unsure.

 

[rhumlady]

The three indicators are for oil pressure, over temperature and charge but I can't remember which is which. I am fairly certain the red is oil pressure . it would be worth removing the exhaust hose from the manifold outlet and giving the elbow a GOOD check over looking for blocked or reduced inside diameter and any sign at all of cracking as when they go they spray hot salty water and exhaust gasses everywhere. Generally reckoned to have a lifespan of around 5 years.

 

[morgandlm]

Bukh DV20

Private message sent

morgan

 

[RobBrown]

I would suspect the PCB distribution plate interfacing the alt charge light, temp & oil pressure senders & alarm.The old design of the board is well known to cause problems. So much so I unnecessarily replaced both the alarm buzzer & the temp sender, but with persistent problems still, eventually realised it was the distribution board itself. There are a number of threads from past years on this topic. I eventually resolved the problem entirely (so far,touch wood) by uprating the diode/resistors on a spare Bukh 20 board passed on to me by Mistroma of this parish. The background to this upgrading is outlined via this link:

http://www.inadee.co.uk/fulmar.htm -scroll down to replacement distribution plate

The link also identifies the 3 indicator lights on the circuit diagram, but to spp answer your question they are from top to bottom, alt charge, oil pressure, engine temp.

You can get pdfs basic owner smanual and the service manual from quite a few free sites eg some here: http://www.earlhill.de/download.html