bukh trouble

I still think the 'stop' operation is pulling fue injection rack back too far, stops engine as required but leaves the fuel setting too low to restart immediately. In my case years back it was possible to force restart by fast turnover (compression levers open, fully charged battery,even start handle cranked at same time to assist or at sea even get sailing fast and engage gear to get prop assist on engine turnover before dropping compression levers) Problem diagnosed eventually by very knowledgeable Bukh main dealer then at Poole Quay , long gone now.

Water in fuel a separate problem but needing fixing, new 'o' ring seal for starters, plus bit of grease on seal and cap threads. Where is filler Is it under water when heeled perhaps or raised above deck/floor?
 
Robin said:
I still think the 'stop' operation is pulling fue injection rack back too far, stops engine as required but leaves the fuel setting too low to restart immediately. In my case years back it was possible to force restart by fast turnover (compression levers open, fully charged battery,even start handle cranked at same time to assist or at sea even get sailing fast and engage gear to get prop assist on engine turnover before dropping compression levers) Problem diagnosed eventually by very knowledgeable Bukh main dealer then at Poole Quay , long gone now.

Water in fuel a separate problem but needing fixing, new 'o' ring seal for starters, plus bit of grease on seal and cap threads. Where is filler Is it under water when heeled perhaps or raised above deck/floor?
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I'm not using the stop mechanism, its just dropping to tickover to berth and the engine stops.

Filler is high up outside the coaming, so I will do the O ring seal, and for now get a bigger water trap, as it doesn't take much to fill it.

I checked the trap at 15 minute intervals as I approached the mooring yesterday. It was clear at the time of arrival when the engine died. so I think the stopping is a separate problem. from the water.
 
When the engine is throttled back to idle from high revs on a DV20, the fuel rack closes completely on the fuel high pressure pump until the engine revs are met. The yolk on the fuel pump rack then moves back to open up the fuel pump to maintain idle. Maybe the fuel rack is jamming when it is closing the fuel pump at idle and not returning to the open position.

Once the engine is stopped and the stop solenoid is disengaged, the fuel rack should return to the fully open position (towards the back of the engine) ready for starting. The DV20 always starts with the fuel rack in the fully open position irrespective of where the throttle cable is set.

On the DV20 it is possible to remove the stop solenoid and feel with fingers the positioning of the fuel rack / yolk. in the forward position the fuel rack is set to closed. Don't know if this is poosible on the 10?
 
Re-reading your post no.19, it seems like you are now having a different problem to the original problem. Orignally it would not restart for quite sometime, now it restarts quite quickly afterwards.

I dont believe in coincidences usually, but it does seem like a different problem now, especially with all the water in the fuel. It now sounds more like a fuel starvation problem possibly caused by blocked filters or the abundance of water.
 
stevd said:
When the engine is throttled back to idle from high revs on a DV20, the fuel rack closes completely on the fuel high pressure pump until the engine revs are met. The yolk on the fuel pump rack then moves back to open up the fuel pump to maintain idle. Maybe the fuel rack is jamming when it is closing the fuel pump at idle and not returning to the open position.


Once the engine is stopped and the stop solenoid is disengaged, the fuel rack should return to the fully open position (towards the back of the engine) ready for starting. The DV20 always starts with the fuel rack in the fully open position irrespective of where the throttle cable is set.

On the DV20 it is possible to remove the stop solenoid and feel with fingers the positioning of the fuel rack / yolk. in the forward position the fuel rack is set to closed. Don't know if this is poosible on the 10?
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You sound like you know the innards quite well..
Theres a horizontal m6 adjuster bolt/locknut behind the governor. Do you know what it does and/or how to adjust it? it is completely ignored by the workshop manual. could that hae a bearing on my problems?

If I exercise thew stop valve when it has cut out, would that reset the governor?
 
stevd said:
When the engine is throttled back to idle from high revs on a DV20, the fuel rack closes completely on the fuel high pressure pump until the engine revs are met. The yolk on the fuel pump rack then moves back to open up the fuel pump to maintain idle. Maybe the fuel rack is jamming when it is closing the fuel pump at idle and not returning to the open position.

Once the engine is stopped and the stop solenoid is disengaged, the fuel rack should return to the fully open position (towards the back of the engine) ready for starting. The DV20 always starts with the fuel rack in the fully open position irrespective of where the throttle cable is set.

On the DV20 it is possible to remove the stop solenoid and feel with fingers the positioning of the fuel rack / yolk. in the forward position the fuel rack is set to closed. Don't know if this is poosible on the 10?
Click to expand...

A much clearer explanation than my efforts of how the speed regulation works and a momentary hesitation could cause a stop :encouragement:.
 
I keep replacing the filters, but it doesn't fix the problem,
nobody else has to repplace filters on every outing. I have yet to id the source of the water, but he CAV prefilter and water trap doesn't seem to protect me much.
Even if the trap is clear the engine stops when reduced to tickover.
I try to reduce the revs gradually as suggested above but I'm then fearful of it cutting out even earlier!.
 
chewi said:
Theres a horizontal m6 adjuster bolt/locknut behind the governor. could that hae a bearing on my problems?

If I exercise thew stop valve when it has cut out, would that reset the governor?
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You shouldnt neeed to touch that M6 adjuster at all.

You could try engaging the stop solenoid. The slightest of taps from the solenoid might free up the rack.....that is of course if it is the rack that is jamming. You could also try gently tapping the fuel pump with a small hammer to see if that frees up the rack.

I am still puzzled as the nature of the problem seems to have changed since the injector was changed. It does make me think there is more than the one problem. I think I would continue diagnosing the problem with the following;

1. I would get the original injector tested, to see if there was any fault there.

2.In the meantime, sort the water in fuel problem out, drain / syphon the bottom of the tank to remove the water and any other contaminents. See i fthat resolves the issue.

3. Remove the stop solenoid to see if you can gain access to the fuel pump rack / yolk. and see if there is free movement. Try pushing the yolk forwards to the fuel cut off position with your fingers. Once released the fuel rack should return to the open position. If not, you need to find out why. If it moves freely I would do the next step.

3. Try and create the problem in a safe place, ie running the engine in gear for 1hr (or however long it takes) whilst tied up to a pontoon and running the engine in gear. without engaging the stop solenoid (engine has cut out on its own)I would remove the stop solenoid and see what position the fuel rack is in. If it is in the forward closed position there is a fault. If not and the fuel rack is in the open position, the problem is likely to be else where.

At the moment, I wouldn't be adjusting anything, I would be trying to find where the problem lies, otherwise you could create more problems, which will throw you off the original problem.

I only have knowledge of the DV20, as I have had to sort a lot of probelms I had with it when I bought the boat, but I assume it is very similar to the 10. I am no mechanic, or an engineer, far from it. I only know what I have picked up along the way from this forumand from other sources, but I have picked up a few things in my Bukh ownership. I buy all of my parts from TW Marine in High Peak as they are really knowledgable on the Bukhs, and they are very patient at giving out advice to me in easy to understand terms. Could be worth running your issue past them.

Another thing I do on my engine annually is to clear the water journals of the salt deposits as they block quite easily. I do this by running Rydlyme through the water system. I am sure your engine isnt cutting out from overheating, but doing this as part of the maintenance will do your DV10 no harm.
 
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Just another thought, as you know about injectors, could the water be passing your filters (it shouldn't but I guess it could as the cav filters aren't a "true" water seperator) be getting to you injector and causing it to fail over time? I know nothing about injectors but I am guessing it could be a possibility?
 
chewi said:
I keep replacing the filters, but it doesn't fix the problem,
nobody else has to repplace filters on every outing. I have yet to id the source of the water, but he CAV prefilter and water trap doesn't seem to protect me much.
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I dont know anything about your particular engine, but if you are having to do that everytime you go out, my priority would be sorting out your fuel. No diesel engine likes carp fuel.
Finding where the water is getting in ( the filler most likely ) then cleaning the crud out of your tank after draining off the fuel and water. If it is as contaminated as it sounds you will have to deal with it rather than leaving it to your filter, some of these lumps of crud in the tank can partially block fuel lines and tank shut off valves as I found out during a clean out. Sort out the fuel, then look at the engine :encouragement:
 
chrishscorp said:
I dont know anything about your particular engine, but if you are having to do that everytime you go out, my priority would be sorting out your fuel. No diesel engine likes carp fuel.
Finding where the water is getting in ( the filler most likely ) then cleaning the crud out of your tank after draining off the fuel and water. If it is as contaminated as it sounds you will have to deal with it rather than leaving it to your filter, some of these lumps of crud in the tank can partially block fuel lines and tank shut off valves as I found out during a clean out. Sort out the fuel, then look at the engine :encouragement:
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Yes, I agree.

In his first post the OP wrote "..starts ok with no throttle, ticks over, runs OK at power for hours.."

That doesn't sound like a sick engine.. Overhaul the external fuel system before doing anything else; even if only to eliminate it as a source of the problem.

He could even try rigging up a small temporary fuel tank using a suitable container and see if the problem disappears.
 
The stop valve appears to be OK, not sticking.
Once the engine stopped again after a couple of hours running I restarted it and it was running very slowly, liuke it does before it eventually stops. I pumped the lift pump manually while the engine was running slow and it accelerated.
Since the governor is supposed to regulate the speed, and the pump should deliver more fuel than is needed, It threw suspicion on the lift pump, so I have removed that for a service.
The water in fuel issue seems to be diminishing now, but we haven't had rain for a few days. I think that reinforces the filler cap diagnosis. Thanks all.
 
chewi said:
The stop valve appears to be OK, not sticking.
Once the engine stopped again after a couple of hours running I restarted it and it was running very slowly, liuke it does before it eventually stops. I pumped the lift pump manually while the engine was running slow and it accelerated.
Since the governor is supposed to regulate the speed, and the pump should deliver more fuel than is needed, It threw suspicion on the lift pump, so I have removed that for a service.
The water in fuel issue seems to be diminishing now, but we haven't had rain for a few days. I think that reinforces the filler cap diagnosis. Thanks all.
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.

Did you ever get this sorted out or were you overtaken by lockdown?
 
No. as you say lockdown prevented me launching so I'm stuffed for the moment. I cant replicate the circumstances ashore.
 
chewi said:
No. as you say lockdown prevented me launching so I'm stuffed for the moment. I cant replicate the circumstances ashore.
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OK, I was "unwatching" some threads that had interested me at the time and yours was one of them so I wondered how you had got on with it.
 
I know this is probably a daft suggestion but have you tried starting the engine when it fails with the filler cap undone. I am wondering if there is the possibility of a blocked breather causing the tank to create negative pressure and reducing the flow of fuel to the engine. It would give you some of the symptoms you are suffering, especially the fact that after a while you can re-start the engine. Won't cost anything and may be worth a try.
 
I didn't resolve this last year
Covid-19 & club limitations force me not to launch this year.
I dont want to haveanother season of wondering if I can stop when I berth, soI am replacing the engine.


i have seen similar symptoms reported for a beta 20 in this thread
Diesel fuel return line

here there have been diagnoses of
tappets,
fuelbug
fuel clips
rust flakes in the tank
air leaks in both feed and return.
poor compresion,
uel retiurn being laed back t o the flow instead oof the tank...
and
lack of a pigtail in the fuel return.

ie almost everything.

some forumites say what have you changed, assuming only one thing has, then they suggest changing other stuff.
But when you have a problem you can't fix so you write into here you have changed almost everything already.

my tank i s above the engine so I dismiss the air in the fuel.
leaks would manifest in diesel in the bilges wuth a high tank
my tank is stainless so i dismiss the rust.
my engine runs hours at full pelt so I dismiss the fuel bug, and I cleaned it.
The bukh is designed to take the fuel return back to the fuel flilter (not the tank)
I cleaned the tank and the lines.

It still ran down to tickover and beyond then stpped and would not respond to the throttle.


I've no idea but I've had enough of praying at the destination.
I'm changing the engine now to a beta 20. (ironic or what)

I will soon have two spareBukh 10 dvme's
 
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