URGENT ! HOW TO STOP A DIESEL ENGINE ?!

[Babylon]

Just finished oil change on Beta 25, started engine to distribute oil around etc BUT IT WON'T STOP WHEN I PRESS THE "STOP BUTTON" !

HAVE I DISCONNECTED SOMETHING BY MISTAKE AND WHERE?

 

[RJJ]

Fuel shut off??

Clothing or a cushion over the air intake??

 

[Babylon]

Panic over - I found the lever on the side of the engine which stops it. It's been a very long day...! Desperately need a beer now and some grub, will troubleshoot the cause in the morning.

 

[Boater Sam]

You have lost the ignition feed to the stop solenoid. Ignition switch on?
I bet you have stood on the wiring loom and lost the connection at the daft multiplug in the loom near the engine.

 

[Babylon]

That must be it Sam... I'd had a pig of a time all day, mainly taking the entire raw water system apart to solve the mystery of no cooling flow (now solved, including also servicing the fresh water side etc), then couldn't get the air filter housing apart to change the filter as it had self-welded with rust (solved), then gearbox and engine oil changes... so plenty of opportunity to inadvertently dislodge some pesky wiring connection in a completely unobvious and inaccessible place at the rear of the beast!

Beer's good now however! ?

 

[NormanS]

I had the same last week when running my engine prior to launching, but I knew about the manual stop lever on the fuel pump. I haven't had time to investigate the problem, but I hear a click at the stop solenoid, so I suspect that the solenoid still thinks it's on its winter holiday and is sticking. Maybe needs a tap with a persuader.

 

[Babylon]

Good point thanks, but the engine was running and stopping previously during the day, and there's no clicking... so it has to be an electrical connection that's been dislodged somewhere around the nether parts of the engine! Will have a gander after breakfast.

It's been so long since I'd first learnt about marine diesel engines and had forgotten about the mechanical method... but had the manual to hand and quickly spotted the useful little photo of the stop lever.

PS where the raw-water cooling problem was I don't know - there was no obvious blockage anywhere from the seacock to the H/E stack outlet - but taking it all apart and reassembling it solved that problem.

 

[Malish]

Just a quick general comment on the thread

NEVER consider stopping a diesel by putting your hand over the air intake - it will hurt!
A piece of plywood, washboard, chopping board or something similarly solid over the air intake are far better options (imho)

 

[Boater Sam]

Just a quick general comment on the thread

NEVER consider stopping a diesel by putting your hand over the air intake - it will hurt!
A piece of plywood, washboard, chopping board or something similarly solid over the air intake are far better options (imho)

Likewise using a rag, it is likely to get ingested by the engine.

 

[WoodyP]

Likewise using a rag, it is likely to get ingested by the engine.

The air intake is that black thing at the rear of the engine and it contains a filter. How is a rag going to get through that lot?

 

[Solent Sailor]

If your engine truly decided to overrun and feed itself on its own lube oil, then trust me you'd want to stop it! Had this happen on a tractor once, wasn't pretty.

Blocking the air supply at the engine is key. Pillow, board, anything that you can get across the inlet. Rags are fine if you can completely wrap a filter, otherwise you may have to pull it off first, in which case a rag could get inside.

 

[Babylon]

Update. Traced problem to a voltage drop at the solenoid positive feed, which only reads 8v when stop-button on the control panel is pressed, then mysteriously rises slowly to 12v over a minute - but only when engine not running; when running it doesn't rise above 8v. Solenoid not the problem as when hot-wiring the positive directly to the main busbar it leaps into action.

Don't suspect the control panel button (dry as inside the boat, although worth checking?), so suspect something unpleasant must be happening inside the wiring loom...

 

[V1701]

I had the same with a Beta 10, in my case the solenoid itself had loosened on it's mounting so it was activating but not enough to stop the engine...

 

[LittleSister]

A good reminder for us all to make sure we know (and perhaps keep aboard a note and/or photo of) where the manual fuel shut off (or other manual means of stopping) is on our particular engine.

 

[dankilb]

something unpleasant must be happening inside the wiring loom...

Try splitting the connector, cleaning, and re-connecting. They’re known to cause occasional problems. As someone said above, it’s easy to knock/pull them while working elsewhere. They come apart very easily!

 

[KREW2]

We have 3 mini series Beta's in our club, 2x20hp and 1x 14hp I have had to change the stop switch on everyone this year. Easy enough to do. Unscrew the panel remove the two crimped push connectors and check for continuity when the button is pressed. While your at it you can check the solenoid is okay by shorting the two wires together. If that is okay, and there is no continuity in the switch you have found your probl.

 

[emmalina]

CO2 extinguisher is the best way to stop a diesel ! Believe me

 

[PetiteFleur]

Reminds me of the time many years ago when I was working on a diesel engined hydraulic pump to which I had just fitted a new larger pump. Starting the engine was fine but when the hydraulic controls operated nothing happened but after a minute or so the engine accelerated and wouldn't stop, the workshop was filling with acrid smoke and in desperation I yanked off the air filter and stopped with my hand... On investigation the new pump had been supplied with the wrong rotation, so the seals blew, the engine filled with hydraulic oil and ran away. Quite frightening at the time as I was the only person in the workshop.
ps I also have a Beta 25 but didn't know there was a manual stop lever - I'll investigate when I visit next.

 

[earlybird]

Don't suspect the control panel button (dry as inside the boat, although worth checking?), so suspect something unpleasant must be happening inside the wiring loom...

Betas have a multi-pin connector to connect the panel to the engine loom, or two if an extension cable is used. Could be a connection in there. The wire to the stop solenoid is Bk/W.
I don't think that I'd make a habit of putting power on the solenoid for extended periods. It might not be continuously rated and could over-heat.

 

[Babylon]

Thanks. What is Bk/W ?

EDIT just got it! You mean black/white... whereas I thought you meant some electrical unit per Watt...!