Expensive sounding click - hoping for a simple fault, expecting an expensive failure

[superheat6k]

So having sorted my starboard engine's alternator, today I checked the drive was till tight after a 50 mile run. After a static inspection, I wanted to check for any signs of wobble under light load. The engine initially started then within a few seconds I heard a loudish click and the engine promptly stopped, then within a few more seconds the power to the engine instruments failed entirely.

The latter turned out to be a dodgy battery isolator switch, but when I restored power, whereas the engine would spin freely it refused to fire. I checked the stop solenoid which was quietly clicking as power was applied (power on to run), but the engine did not fire.

When it first stopped it was as though the engine had stopped on the stop solenoid as for any normal stop, although I do not recall hearing the click noise previously.

So it seems either the stop solenoid plunger has stuck in the stop position, the fuel lift pump has failed, or (worse case) something has snapped inside the fuel injection pump.

Further investigations commence in the morning.

Has anyone similar experience of a distinctive click noise when stopping a Cummins engine equipped with Lucas DPA type injection pump ?

 

[rafiki_]

Trevor, might be worth contacting Latestarter1? If anyone has any knowledge of this then he will.

 

[Colin K]

Hi Trevor,
When you say sorting out the alternator was that a replacement? This click do you think its mechanical or could it have been a major short. Seems a bit of a coincidence working on engine electrics, dodgy isolator,not starting/clicking.
There hasnt been a major short/power spike has there that has now wiped out the stop solenoid?. Just bouncing ideas. I guess first job will be getting a meter on the solenoid.

Good luck, Col.

 

[superheat6k]

Hi Trevor,
When you say sorting out the alternator was that a replacement? This click do you think its mechanical or could it have been a major short. Seems a bit of a coincidence working on engine electrics, dodgy isolator,not starting/clicking.
There hasnt been a major short/power spike has there that has now wiped out the stop solenoid?. Just bouncing ideas. I guess first job will be getting a meter on the solenoid.

Good luck, Col.

The alternator was replaced last year after an identical failure of the taper lock that holds the drive multi vee pulley to the shaft. I fixed this but wanted to check it after a run. The reason for the electrical failure was completely separate, but certainly three issues all occurring in close succession.

I bypassed the failed switch temporarily to retry a start, and have checked the voltage at the stop solenoid when the engine is in run position (yes), and it is their plus a faint click can be heard. I have been re-thinking the sound I heard, and it could be described as a click or a even a metallic snap. Definitely no grinding or other nasty noises. The engine spin sounds fine, just does not fire. I am convinced this is a fuel injection issue of some sort.

I will put the ammeter in series with the stop solenoid tomorrow and see what power it draws then compare with the Port engine solenoid. There is also a small inspection window on the side of the fuel injection pump, although finding out what you can inspect inside is somewhat elusive.

A Cummins agent engineer I have spoken with did advise that I can remove the stop solenoid plunger and then attempt a re-start and if this fixes it then I know it is time for a new stop solenoid, but I must make sure I can stop the engine either on the fuel supply or there is a mechanical stop lever that is otherwise not used. Operating this you are up close and personal with the engine and its running belt and pulleys, so no loose clothing for this one, although I should be able to fix a short cable to use as a remote stop link.

After that the next job will be to disconnect the outlet pipe from the lift pump and see if fuel squirts when the starter spins. My thinking here is that the snapping sound could have been the drive tang snapping off, although I doubt that is the case, as I figure the engine would have run on for longer than literally a second or so after the noise was heard, but easier to remove and check the lift pump first than the injection pump - the items requiring removal first plus setting the engine up to TDC on cylinder 1 and locking both it and the fuel pump at that position will be a most of the day job I expect to get the damn thing off.

I think the worst case here is a sheared injection pump drive shaft. In which case time for some open wallet surgery (after a lot of swearing ! ).

 

[burgundyben]

Trev I'm in Denmark. Back later today. Pm me a number and I'll take you through it.

 

[Firefly625]

look, I am no engine guru Trevor, you are far more technically able. But having been close to my Perkins (and other engines) when the stop solenoid operates its is a surprisingly loud Snap it makes. Obviously normally deadened by soundproofing and general engine noise, but when your ear is close it is a loud snap. I hope this is the issue as would be the cheapest... also if it was fuel related issue it would have run on a bit before stopping I would have thought...

But Ben will on it I am sure.

 

[vas]

T.,

how easy is it to swap stop solenoids?

hope it's something minor like that...

cheers

V.

 

[superheat6k]

Trev I'm in Denmark. Back later today. Pm me a number and I'll take you through it.

Ben - PM sent I would appreciate a call in the morning. I have taken the pump off as I fear a sheared shaft.

A precis of what I checked today ...

1 Replaced duff battery isolator, and attempted a start - no joy

2 Checked fuel flow from lift pump and also no air gathered at injection pump - vented at filter top and injection pump, but no air just plenty of fuel as lift pump operated. I also checked that the lift pump was picking up on the cam, and at certain positions it was clearly on stroke.

3 Barred engine to engage timing pin, nearly broke middle finger when barring wrench slipped and after much swearing the finger still hurts many hours later.

4 Removed inspection cover to observe internal element rotating.

5 Set pump drive to key at top position and locked pump drive.

6 Undid connections and removed pump.

Dismantling of the governor tomorrow when I will see if I can work out if the hydraulic head is rotating.

Having studied the internal view of the DPA pump for several hours I can't yet work out a simple way of knowing whether the hydraulic head is actually rotating without undertaking an extensive dismantling. However, it looks like the output is set by the governor.

Once I have found out what has happened, if anything ( ! ), I will then consign to to a specialist for fixing / testing.

 

[Firefly625]

Good luck Trevor with your investigations, hope your finger recovers!

 

[burgundyben]

Still only on my phone.

Google 'cummins cav dpa' find sb marine top hit. Should be able to download load cav pump manual.

P B Asher in West Quay Road. Right near BSA Regal are the people to go to.

I think highly unlikely it's poorly. Two levers on top. One is the loud pedal. Other is stop solenoid. Underneath is a round device. 3/4" diameter. Looks like a temp sender but longer. Has two 1/4" spade terminals. It's an energise to run solenoid. Either 12 or 24v supply to one terminal when ignition on. Other terminal to ground. Do you have volts there? Suspect fiddling with alternator you've accidentally killed this supply. (Very vague idea there might be a fuse in loom to this supply)

There is a plastic pin know end of energise to run solenoid which you can remover. Then refit solenoid. Doing that kills it's function. So bypassing get it to test run.

 

[superheat6k]

Still only on my phone.

Google 'cummins cav dpa' find sb marine top hit. Should be able to download load cav pump manual.

P B Asher in West Quay Road. Right near BSA Regal are the people to go to.

I think highly unlikely it's poorly. Two levers on top. One is the loud pedal. Other is stop solenoid. Underneath is a round device. 3/4" diameter. Looks like a temp sender but longer. Has two 1/4" spade terminals. It's an energise to run solenoid. Either 12 or 24v supply to one terminal when ignition on. Other terminal to ground. Do you have volts there? Suspect fiddling with alternator you've accidentally killed this supply. (Very vague idea there might be a fuse in loom to this supply)

There is a plastic pin know end of energise to run solenoid which you can remover. Then refit solenoid. Doing that kills it's function. So bypassing get it to test run.

Thanks Ben. The lower stop solenoid is working fine - with the ignition on 12v is three and disconnecting the supply I can hear it click. I also tried removing the solenoid armature pin but still the same.

I will contact P B Asher. Thanks for that.

 

[superheat6k]

So I have removed the pump, what a job that was - up there with exhaust hose replacement on the Corvette, and cutlass bearings on a Turbo 36 for sheer pleasure, and wrecked fingers !

Thankfully there doesn't appear to have anything wrong with it, but it will now be properly tested to confirm all is OK.

Can't wait for the joy that will be putting it back on the engine. There is one mount nut that I have yet to figure how to get started on its thread. Hey ho.

 

[Mr Googler]

So whats next if the pump is ok? Back to fuel solenoid? So sorry to hear of your troubles!

 

[Portofino]

Bit late now ( pump ,s off ) but ------
Did you not think to crack open a fuel union on a injector or all of them ?
Turnover the engine to see if fuel was arriving ?

Just read this thread ,not wanting to sound critical .

 

[burgundyben]

There is one mount nut that I have yet to figure how to get started on its thread. Hey ho.

I know the nut you mean. You need a 1/4 drive socket for it, with a long 1/4 drive wobble head extension, you need to fill the socket with an extra nut, so the nut you want to fit not deep inside the socket, stick them into place with grease.

Edit - forgot to say. Remember to check what I said on the phone, wasn't a clear line as I was driving, check voltage drop on the energise to run pin when cranking. Also, did you refurb the battery isolator? Or replace? How confident are you that's not struggling to cope with the current and causing v drop that's hitting the solenoid when cranking?

Call me in the week if you want.

 

[superheat6k]

I know the nut you mean. You need a 1/4 drive socket for it, with a long 1/4 drive wobble head extension, you need to fill the socket with an extra nut, so the nut you want to fit not deep inside the socket, stick them into place with grease.

Edit - forgot to say. Remember to check what I said on the phone, wasn't a clear line as I was driving, check voltage drop on the energise to run pin when cranking. Also, did you refurb the battery isolator? Or replace? How confident are you that's not struggling to cope with the current and causing v drop that's hitting the solenoid when cranking?

Call me in the week if you want.

Thanks for that tip Ben. I did check the voltage whilst cranking after I had replaced the duff isolator. Anyway the service at PB Asher seems excellent. I had an email reply to my enquiry by 9.15 and I dropped the pump off to them this evening.

Their advice was that an internal inspection and test was prudent, and this is £100. If they find something is broken and a refurbishment is required somewhere around £250 - 350 for this model pump, subject to what parts are needed, so not so much to cry over. My initial thoughts were Cummins and a few BOAT for a replacement.

 

[rafiki_]

Thanks for that tip Ben. I did check the voltage whilst cranking after I had replaced the duff isolator. Anyway the service at PB Asher seems excellent. I had an email reply to my enquiry by 9.15 and I dropped the pump off to them this evening.

Their advice was that an internal inspection and test was prudent, and this is £100. If they find something is broken and a refurbishment is required somewhere around £250 - 350 for this model pump, subject to what parts are needed, so not so much to cry over. My initial thoughts were Cummins and a few BOAT for a replacement.

Good luck with this Trevor. Will we see you on Saturday for the Regatta?

 

[superheat6k]

Good luck with this Trevor. Will we see you on Saturday for the Regatta?

Paul Hope to come down. We normally end up at a party on a friends Bavaria 47 stick and rag thingy - South Point II. Normally they moor it near by to your mooring. We use our boat as a convenient B&B.

 

[rafiki_]

Paul Hope to come down. We normally end up at a party on a friends Bavaria 47 stick and rag thingy - South Point II. Normally they moor it near by to your mooring. We use our boat as a convenient B&B.

Great, hope to see you at the weekend.

 

[superheat6k]

That Peaceful Easy Feeling arrived this afternoon when the starboard engine started.

The service of P B Asher is first class. The pump they have tested has been fully stripped and inspected and not only a new seal kit, but also fully shot blasted and calibrated.

Thanks to Ben for his tip on getting the unreachable mounting nut on - only took me ~30 minutes of the 3 hours total to reinstall the injection pump.

Tomorrow's task is to clean off the mass of tools I seem to have used and then clean the engine bay.

Although there was nothing broken within the pump, they felt the click / snap noise heard warranted the full strip and they did find the calibration slightly adrift.