BUKH 20DV Engine. Ignition Issues

[OOC]

Recently had my engine serviced. Was a good starter and ran well. Has developed an ignition issue. It will not ignite. It turns over strongly and the batteries are charged and fairly new.The fly wheel rotates and it is straining to start. However, once i turn the ignition key on it will not stop the by turning it off. The engine keeps turning over and trying to fire. I either have to use the decompression levers or turn off the battery power. I replaced the ignition block but the problem is exactly the same. I am not experienced or very knowledgeable with electrical matter.

I studied the circuit diagram, and checked the wiring through as best I am able., and as far as I can tell there are no obvious cable or wiring breaks or interruptions. I hired a mechanic and he hotwired the switch and after a while it fired up and ran and took it out for a short run on the engine only. ALl seemed fine. Reconnected the switch- same problem. Mechanic attended again and together we tried to start he but the engine was just turning over but not igniting. Ran it for a few seconds with compression rods released to allow free wheel; whenrods put in running mode- would not fire.

Although it took a while( it's cold right now and recently) when hot wired it worked. That to me would seem to preclude a stale fuel or other issue. It won't turn off- that's obviously a switching/electrics problem. I can't see any fuses or fuse blocks near the ignition switch; took off the electrical panels inside- don't see any fuses there. After the ignition block all the cabling goes into the original sheath and then presumably through to the electrical panel below.

Any ideas please? I don't want to keep trying and burn out any electrical components. I have bio-diesel additive in but the fuel is from September . Oil warning sensor was replaced recently but no lights or alarm coming on when trying to fire up. Was reading about similar difficulties from other memebers and solutions including heating via air intake; drops of oil into fuel supply etc. But don't wish to try that if it's a pure electrical issue.

Are there any inline fuses I can check in this system? Will post circuit diagram later on today.
Thanks

 

[j_schoenfeld]

This is a diesel correct? The way my universal 5411 shuts off is the throttle. I push it down and it cuts off the fuel. As far as I know the only way to shut off a diesel is to cut off the fuel from the injectors. I used to skipper a Ranger 28 and it had a plunger that you pulled to kill the fuel. Maybe you have an electric solenoid that will shut off the fuel. What kind of diesel is this and in what type of boat?

 

[OOC]

Thank you for your reply and time.
It's a Bukh 20DV engine. It is a 33' Canadian Sailboat( CA33). Common engine with this boat. Yes It has a solenoid to stop the engine. I had some issues with it a year ago but replaced it and it worked fine until recently. I have to check tomorrow when I am over atthe boat; to see if the lead on the solenoid is detached and /or any other problems I can diagnose with previous experience. If it's that then it should stop the engine when the key is turned to off and solve the problem. Then I need to check all the sensors for the oil, water and temperature; which seem to be on the blink as well. I just was wondering if there are any fuses in the electrical system that may have failed. However the igniton block is a solid unit and the wiring is fairly basic and visible and there ae no fuses visible behind it. Likewise at the control panle- no fuses visible. In between the wiring is sheathed and ticked behind various fittings etc. and I don't think there will be fuses in there.

So Solenoid check and report back.
I am going to try spinning the fly wheel with the ignition on and the comprssion off so it's in free wheel mode for about a minute. A tip I saw elsewhere on the forum. It may just be inactivity and the solenoid.
Hopefully so.I have seen the plunger /pull stop systems and also had a boat withthe throttle being the kill switch. This engine is killed by turning the key anti-clockwise and holding a few seconds- so that's the solenoid.

Thanks again. I will report in tomorrow.

ONC

 

[OOC]

Yes.
It is a diesel engine.

Here's a great sailing solution to the CV19 crisis,

'Focus only on what you can control': A solo round-the-world sailor on isolation

Dee Caffari has been alone at sea for as long as six months. She gives her tips on how to cope with solitude during the coronavirus outbreak

www.theguardian.com

 

[Davidasailor26]

I’m a little confused by the symptoms. It sounds like the starter always turns when you put the key to start, correct? Just that sometimes it won’t keep running? And then sometimes once it is running it won’t stop?

If I have the above correct, my guess is that the fuel cutoff is not functioning properly. If the cutoff were stuck in the off position the engine won’t run, and if it were stuck in the on position then the engine won’t shut off. It’s less likely that there are multiple concurrent problems, so if I understand the symptoms correctly then that would be my guess at the root cause.

 

[jssailem]

Ok I discovered one of the issues. It’s Danish built. Did you get an English manual?

Diesel engines are basic. Fuel. Air Compression.
Are you getting a constant flow of clean fuel to the cylinders. Is it sprayed into the cylinder in the right mix. Is the engine getting air? Do you have compression?

When shutting down a diesel you take away one or two of the things that make it fun. Most often fuel, but some engine makers choose to take away compression. Since you said you can “spin” the motor I am guessing you have a compression release. Be certain the release is disengaged so the engine had compression when attempting to start. Be sure your duel system is primed and all your duel filters are clean. Have a supply of clean fuel in the tank. Make sure your air filter is clean.

Cross your fingers and hope the Danes gave you a good one.

 

[OOC]

Very nice replies. Very helpful. Thank you very much all posters.

I do have an English manual. I have been thinking about waht you have pointed up and am going over today to try a few things I have learned from experience. It's generally a good engine; just been tricky this month. I had filters replaced and new gaskets etc. I have not primed the fuel- there is a little riser pump; and I can release the nut on the injector to let any air out. That was one previous problem like this that I solved. Also I am going to check the solenoid and carry on, s you suggest, putting the engine in compression before trying to start it..

My ' kill switch' as is the ignition and he solenoid. Turn off; solenoid kills the fuel supply Has a piston which is driven into the tube it sits in.

It's not an alternator problem as far as I can see as the large fly wheel spins as does the alternator. Batteries are fully charged.

So thanks for making me think it through more effectively.
The 'symptoms' come down to: It turns over, with compression; and in 'free wheel and keeps on doing so- even when I turn the new ignition switch off( there seemed to be nothing wrong with the one i removed). So it keeps spinning but does not ignite and has to be turned off either at decompression levers or the electrical switch. I don't like, intinct only, doing the latter ( or the former really) as I fear it may burn out some electrical components if I do it too many times.

These symptoms point to a solenoid and a non-bled engine if I Am lucky!

Thanks again for the help.
ONC

 

[j_schoenfeld]

As I re-read your post I caught something I didn't catch at first. If you have no gauges you are missing power somewhere, and the solenoid would need power to work. As with most problems on a boat, it's probably a ground somewhere.

 

[OOC]

Thank you.
How would I check for a ground please- at which points. I have zero ability with electronics- as you realize.
I have one of the little screwdrivers that light up.

 

[OOC]

I can borrow a pair of the minature red and yellow testing cables with crocodile clips on them. My freind used them to start the engine and by pass the switch a few weeks ago- he has a long coiled cable with aclip on too that he used to test for a ground- I just don't know the technique.

 

[jssailem]

Based on what I am hearing I would look to the Fuel as not getting to the injector. You should not run the starter for more than 15-20 seconds. To long and you may introduce water into the engine backing up from the exhaust system. Or burn up the starter, or kill the battery charge.

You said the filters were changed. You might check the filter fittings to be sure there are no air leaks in to the fuel lines. Fuel should flow from the tank to the filter to the engine. Sometime gunk finds it’s way into this system. Checking each stage is a normal way trouble shoot this system. Make sure the pick up tubes are clear of debris. The fuel lines let fuel flow into the filters. Then through the lines to the engine.

I have a manual lift pump on my engine. I use it to make sure I have fuel from the tank to the line out of the filter on the engine (open the line a bit coming out of the filter to the engine injectors hand pump till fuel shows up.) When I have fuel at the filter I go to the next step.

You can run the starter to help prime the engine -

• turn off the raw water to the engine,
• open the fuel line on the injector,
• turn over the starter till fuel begins to show at the injector.
• Stop the starter
• close the injector fuel line.
• Open the raw water,
• Try to start the engine. Confirm the compression release is closed so you have compression to fire the engine.

If no fuel when you try this procedure then I would look at the solenoid and confirm that the wires are connected properly. You will need a volt meter to check the wire connections.

Good luck

 

[OOC]

Just going over now to try all of this. Will report back.
Again- Thanks.

 

[twalker H260]

When did the solenoids/switches get replaced? Did they wire it correctly? Sounds to me after dealing with two ignition switches that the problem likely lies in the wiring of the system. Starter should NOT continue to turn when switch is released from start position. This can only happen when starter solenoid continues to receive power after key is released and when turned off it is still continuing to receive power. I would suspect that perhaps the fuel solenoid is not receiving power during this time to allow fuel flow. By hot wiring I suspect the mechanic likely got the wiring temporarily correct.

can you post your wiring diagram? Perhaps we can help trace the issues through that with you.

 

[OOC]

Soooo.....It's hardly credible.

Had a mechanic working on the boat a month ago.
He was supposed to fix a persistent but innocuous oil leak.

Finally after much faffing about he got it done. Today after all the help and thinking I started at the injector heads.

Plan was to crack them and crank the engine. Both were wide open as far as they could go.

Had been so for a month..source of the problem.
Pumped fuel through using the riser pump.
Replaced riser pump lever in locked down position- essential with Bukh 20DV as she won't start otherwise.

Turned the switch- fired up immediately. Ran for ten minutes. Turned off.. Switch worked perfectly and engine just as it always was.

I could hardly believe my luck!

Which lasted about 10 minutes!

Now there is no water pumping out.
Took out the impeller, which was new last month, and examined it..seems ok.
I suspect some kind of air leaking in....but did not have enough time for a full shakedown.

I will publish the wiring diagram as I think they are quite rare and it may help someone else one day.

Thanks everyone.

I don' t think the water problem is linked to the injector problem...but what do I know!

ONC


Cheers

Afterr the

 

[jssailem]

Take the win. There is time tomorrow to explore the next project.

 

[OOC]

So I now have the engine starting and stopping on the new ignition switch.
I don't have the alarms or oil pressure switches but think this must be a sensor issue and am going to check all of the diagrams and do the best I can to see if they are connected up to the correct sensors. I will also post the electrical diagram later on when I get the chance today or tomorrow. It shows all the individual sensors and their shape and function.

I have new problems but not sure if I should post them under this thread o a new one.
I am going to outline them here and then post them under a different heading in a little more detail.

Any ideas on the switching and alarms/sensors will be helpful.

Thanks all and stay safe.

 

[jssailem]

Yes Post on a new thread.

Sensors. Check ground wire is clean and secure. Check that sensor wire connection is solid and clean. The sensor is designed to seal as it screws into the engine. Sometimes well meaning persons will coat the sensor threads with teflon tape or locktite. This can disrupt the electrical connection needed to connect the sensor to the engine block. You can check the sensor threads.

My bet will be a poor ground connection.

 

[sailme88]

Check your exhaust....If there is back pressure caused by an occluded exhaust it won't run....

 

[OOC]

New Issues:

Bukh DV engine:
Had a mechanic work on the raw water cooling system.I'm familiar with it and can take apart and replace impeller and check the thermostat and reinstate etc. However, lst time I started up the engine, first time since mechanic finished working, there was no water pumping out of the exhaust. Usually a healthy flow. Around the big ' heat exchanger unit' which is at the starboard stern with large inlet and outlet hoses it sounded very ' baffly' and louder than usual ; not the normal low noise output with decent water flow out from the port exhaust.

I turned off sharpish and investigated. As best I could see all of the stop cocks had been turned back on but it was dark and I had no light source under the galley sink. SO this may be my problem. I am going to check today. I also checked the impeller and that seemed fine. Was new and has not been used. The previous one was also new, but there was no water pumping out. After many hours took it apart and found the inner ring had parted from the fins and was just spinning around without moving them. I will check this one again today/tomorrow and see if this has happened again. All hoses and copper pipes are Bukh spares and brand new with correct gaskets etc.

However, if it is not then, having read up on this kind of issue, it takes me out of my current knowledge zone. I watched the mechanic, when he was on the boat, remove the raw water filter. He then cleaned the glass tube, made new gaskets and reinstalled it. I made sure the water in stop valve was in the correct ( horizontal mode and open). From reading it seems a common cause of no water being pumped out/through the cooling system is an airlock? This led me to read about self priming pumps and filter (s) and the process of ' priming them' if the air lock exists/persists?

I could not see any water inside the glass tube of the raw water filter. I will take the right light today and double check. If thee is no water in it does it need 'priming' and how would I do this. My limited understanding is that if it is low enough/below the water line it will be able to self-prime through gravity? It is directly in line with the level of the deep galley sink. The top of the filter is in line with the top of the sink in the under sink recess and the bottom is about half way down the level of the sink. I will get a photo.

I think my water /impeller pump is self priming too? I don't know how to prime that if that is the problem?
My problem diagnostics will be:

I intend to start with all of the through hulls, taps and hoses and check for blockages and correct 'on' positioning inline.
Then check the impeller and reinstate it if OK; or replace it if defective.

Then test if the water flows. If not I would like to know how to prime, (if they need it) , the RW filter and the water pump please.

I can't think of anything else but will report back tomorrow when I have had a chance to see and/or act on any advice received before then about priming.



I have had replies mentioning an 'occluded exhaust' (thank you) and was also wondering if this is my problem? Barring anything ( except water) being sucked into the exhaust it would seem logical to me that any water in the lower sections would block the outflow of cooling water and also backwash to create the 'baffly ' sound in the cooling chamber?

If this is the case how do I unblock an excluded exhaust please? Presumably it needs some large pressure to force any water out ?

I don't know how to diagnose it other than above, or to check or clear it?
For all I know it may be another form of 'air lock'.
Thank you.

ONC

 

[sailme88]

New Issues:

Bukh DV engine:
Had a mechanic work on the raw water cooling system.I'm familiar with it and can take apart and replace impeller and check the thermostat and reinstate etc. However, lst time I started up the engine, first time since mechanic finished working, there was no water pumping out of the exhaust. Usually a healthy flow. Around the big ' heat exchanger unit' which is at the starboard stern with large inlet and outlet hoses it sounded very ' baffly' and louder than usual ; not the normal low noise output with decent water flow out from the port exhaust.

I turned off sharpish and investigated. As best I could see all of the stop cocks had been turned back on but it was dark and I had no light source under the galley sink. SO this may be my problem. I am going to check today. I also checked the impeller and that seemed fine. Was new and has not been used. The previous one was also new, but there was no water pumping out. After many hours took it apart and found the inner ring had parted from the fins and was just spinning around without moving them. I will check this one again today/tomorrow and see if this has happened again. All hoses and copper pipes are Bukh spares and brand new with correct gaskets etc.

However, if it is not then, having read up on this kind of issue, it takes me out of my current knowledge zone. I watched the mechanic, when he was on the boat, remove the raw water filter. He then cleaned the glass tube, made new gaskets and reinstalled it. I made sure the water in stop valve was in the correct ( horizontal mode and open). From reading it seems a common cause of no water being pumped out/through the cooling system is an airlock? This led me to read about self priming pumps and filter (s) and the process of ' priming them' if the air lock exists/persists?

I could not see any water inside the glass tube of the raw water filter. I will take the right light today and double check. If thee is no water in it does it need 'priming' and how would I do this. My limited understanding is that if it is low enough/below the water line it will be able to self-prime through gravity? It is directly in line with the level of the deep galley sink. The top of the filter is in line with the top of the sink in the under sink recess and the bottom is about half way down the level of the sink. I will get a photo.

I think my water /impeller pump is self priming too? I don't know how to prime that if that is the problem?
My problem diagnostics will be:

I intend to start with all of the through hulls, taps and hoses and check for blockages and correct 'on' positioning inline.
Then check the impeller and reinstate it if OK; or replace it if defective.

Then test if the water flows. If not I would like to know how to prime, (if they need it) , the RW filter and the water pump please.

I can't think of anything else but will report back tomorrow when I have had a chance to see and/or act on any advice received before then about priming.



I have had replies mentioning an 'occluded exhaust' (thank you) and was also wondering if this is my problem? Barring anything ( except water) being sucked into the exhaust it would seem logical to me that any water in the lower sections would block the outflow of cooling water and also backwash to create the 'baffly ' sound in the cooling chamber?

If this is the case how do I unblock an excluded exhaust please? Presumably it needs some large pressure to force any water out ?

I don't know how to diagnose it other than above, or to check or clear it?
For all I know it may be another form of 'air lock'.
Thank you.

ONC

If it is the exhaust, the usual fix is to replace the raiser where the exhaust and raw water meet. In many instances the piping here is iron. Your statement re: no water out of the exhaust and an intact impeller suggest that a occlusion/blockage is the culprit.

Good Luck,

Rick