Bmc 1.5 no amps back

[chris1138]

Hi folks, 

 

My bmc 1.5 engine isn't taking back any amps to starter. 

Thinking something loose as I took her down the canal to a fella as I noticed it wasn't working - only for it to work then. 

But then on my way back up - nowt. 

I am new to boats and engines. 

 

I have made a wee youtube video for you to see. Also a loose belt anyone know how to tighten (see in video) 

 

Thanks very much link below 

 

https://youtube.com/shorts/tGTZcJK_XYA?feature=share

 

[MtB]

Engine starts with plenty of energy, then the ignition lamp goes out as expected as the alternator energises.

 

A busted ammeter would be my guess! 

How do you know the ammeter is measuring starter battery current and not domestic battery current?

 

 

[chris1138]

2 minutes ago, MtB said:

 

How do you know the ammeter is measuring starter battery current and not domestic battery current?

 

 

No idea what you mean mate. 

What's domestic battery current? 

 

Sorry, I don't know much about these. 

 

I'm pretty sure it should be feeding amps back to starter. That's how it worked previously. 

 

I just changed my starter . It's used but it seems grand. 

[Tony Brooks]

I disagree with Mike, I don't think the warning lamp goes out until, for some odd reason, you turned the ignition switch off.

 

Sometimes you have to rev the engine to get the alternator to energise, you did that to a degree, but you put it ack to idle almost instantly. As a test, restart it, leave the ignition on and the rev the engine about halfway for a few seconds, see if it works.

 

The belt looks tight enough to at least allow the alternator to energise, even if it slips, so you do not get maximum output.

 

You MIGHT have left a thickish cable off the main starter connection, maybe about 6mm in diameter. That would be the main charging lead from the alternator that is using the main nut type starter terminal as a junction box, but that is in no way definite because we need to know a lot more about your system.

 

I am sorry, but I am having difficulties understanding your writing.

 

I am fairly sure that is a moving iron meter and they are not really suitable for boats today. It may well have burned out but it needs testing and I am not sure you have the equipment (multimeter) and knowledge to do such testing.

 

24 minutes ago, chris1138 said:

No idea what you mean mate. 

What's domestic battery current? 

 

Sorry, I don't know much about these. 

 

I'm pretty sure it should be feeding amps back to starter.

 

In reverse order.

 

Alternators do not feed amps back to the starter, they should feed amps back to the battery or battery banks. As I said it might use the starter main terminal as a connection point to the battery cable, but if you have two banks it may well not.

 

The vast majority of boats, but not all, have two batteries, a single one for starting and then another one, two, three and so on, all connected together, to provide power for the cabin systems, lights, pumps etc. As you only have one alternator the charge needs sharing between both banks, this is what Mike was talking about, he asks which bank is the ammeter measuring.

 

One alternator and two banks implies some form of charge splitting device, so that might be a faulty, as may the alternator itself. I can't help explain testing to you until I know how much you understand.

 

 

 

 

45 minutes ago, chris1138 said:

Also a loose belt anyone know how to tighten (see in video) 

 

 

The belt on just two pulleys (the front one) will be loose because it only drives a water pump, and too greater tension wears the pump.

 

The one on three pulleys is the alternator drive belt. This one should deflect about 10mm under moderate finger pressure in the centre of the longest run between pulleys.

 

Your alternator has three "fixing" points, two at the top that are ordinary nuts and bolts. Loosen these a turn or two. Underneath it, at the front, there is a long flat bar with a slot in it between the engine and an alternator lug. This has a bolt that needs loosening so the bolt can slide in the slot. Then pull the alternator away from the engine to tension the belt and re-tighten the fixings. Warning - do not lever against the middle of the alternator with all the laminations, if you do use a lever keep ii on one of the aluminium end brackets.

[chris1138]

Thanks Tony. 

 

First off, I was instructed to turn the ignition key off when engine starts from gentleman i bought boat off.  I was warned never to have red light on. 

Oh dear! 

I will try what you suggested in morning. 

 

And no, I don't have a clue about a multi Meter but I'm moored in a club so I will ask someone to try for me when I see them. 

 

In terms of banks I only have the one starter battery and nothing else. All my lights , pumps ect work off the starter. 

 

Again, I will try it with ignition key on in the morning , give it some revs and perhaps turning key off was the issue. 

Fingers crossed 

[Tony Brooks]

14 minutes ago, chris1138 said:

Thanks Tony. 

 

First off, I was instructed to turn the ignition key off when engine starts from gentleman i bought boat off.  I was warned never to have red light on. 

Oh dear! 

I will try what you suggested in morning. 

 

And no, I don't have a clue about a multi Meter but I'm moored in a club so I will ask someone to try for me when I see them. 

 

In terms of banks I only have the one starter battery and nothing else. All my lights , pumps ect work off the starter. 

 

Again, I will try it with ignition key on in the morning , give it some revs and perhaps turning key off was the issue. 

Fingers crossed 

 

You are at the start of a massive learning curve. You may find the course notes on my website helpful. www.tb-training.co.uk.

 

The red light on suggests the energisation part of the alternator is OK.

 

The alternator is a Lucas A127. It has a large terminal marked B+. Connect a voltmeter between that terminal and the case. It should read battery voltage with the engine stationary.  If it reads zero or close to it, the other end of that cable is disconnected (probably at the starter).

 

A full alternator testing procedure is in the electrical notes on my website.

 

PS I think this boat is a cruiser, not a narrowboat.

Edited March 30, 2023 by Tony Brooks

[chris1138]

I know Tony regarding learning curve. 

I've had problem after problem with this boat. Which isn't me complaining. 

 

So when running boat, I should switch key back, or leave it turned to right? 

 

It is indeed a cruiser . Its a 1976 buckingham 27ft boyo with enfield z drive. 

It was used little over the last decade. So there's been a few issues.  But I've managed to get her running after months of head scratching, asking questions and some cursing 🤣

 

[Tony Brooks]

28 minutes ago, chris1138 said:

I know Tony regarding learning curve. 

I've had problem after problem with this boat. Which isn't me complaining. 

 

So when running boat, I should switch key back, or leave it turned to right? 

 

It is indeed a cruiser . Its a 1976 buckingham 27ft boyo with enfield z drive. 

It was used little over the last decade. So there's been a few issues.  But I've managed to get her running after months of head scratching, asking questions and some cursing 🤣

 

 

In general, you should leave the ignition on, and turn it off when you stop the engine. On a boat that old that as probably had lots of unskilled attention from previous owners, there is an excellent chance that the wiring etc. is far from what one would normally expect, so I doubt anyone who has not inspected the boat can offer much definitive advice.

 

Your key should have four positions. Off and turning cockwise, ignition on, then against a spring, glow plugs on, and then further clockwise start. If you let go of the key it should jump back to the ignition on position. That is the normal for BMC keys but there are other switches that will work on a BMC, but the glow plug position might be one turn anticlockwise.

 

The ignition on position not only energises the alternator via the warning lamp bulb, but may feed other things like a temperature gauge, oil pressure gauge, and a number of other things possibly, so the switch should be left in the ignition on position when the engine is running.

[chris1138]

Thanks Tony

 

Yes it's anti clockwise to heat glow plugs. Thanks for reminding me as I have an issue with them too. 

 

Wondered also if you knew where to buy new wiring for these. Pictured below are mine. The second of 4 must have come off on previous owner as its taped up . 

This looks like an easy enough job to replace, no? 

It doesn't seem to affect starting engine. 20 to 30 secs on glow plugs and she starts without issue. 

[Quattrodave]

50 minutes ago, chris1138 said:

with enfield z drive. 

 

 

But I've managed to get her running after months of head scratching, asking questions

 

When was it last out if the water, when was your stern drive last serviced and bellows changed?

 

BMC diesels are pretty damn simple, not sure it should have taken you long to get it running.

[Tony Brooks]

Re glow plug cables.

 

Personally, I would just crimp or solder up a new one from terminals and a bit of suitable cable. If you must buy new the maybe Calcutt Boats will sell them.

Edited March 30, 2023 by Tony Brooks

[chris1138]

It was never the engine 

 

I had issues with z drive 

Relying to dave there

The z drive wouldn't go left on me when in gear. Like was really stuck. I had so many people look at it, scratching their heads. 

We lifted the back of her up. 

Turned the z drive round to look too. 

 

Then one day, it worked. And has since. 

Had issues with the morse box too. 

The way the past owner had it was not right. 

Managed to take it apart and sort it. Also had seized cables. 

That's been sorted too

[Quattrodave]

Hmmm rather sounds like the stern drive hasn't been looked after.  Get it out of the water and serviced properly, change seals and bellows.

 

The Enfield 130s are good sterndrives when cared for.  They are a bugger to set up properly.  If not set up properly or cared for they will eat themselves. 

[Mike Hurley]

If it has not had much use in the last decade how old is the battery?

[john.k]

Whats the pulley wobbling all over the place ...a bilge pump....water circulation pump?.....may need fixing.

[David Mack]

19 hours ago, MtB said:

Engine starts with plenty of energy, then the ignition lamp goes out as expected as the alternator energises.

The engine starts fine and I would have thought the initial revs should be enough to get the alternator started but maybe not. The revs settle to a slow idle and the ignition switch is turned back to the off position, and the ignition light goes out. So all the later reving of the engine is bound to have no effect on the charging. OP should try revving the engine with the key in the run position, and that should cause the light to go out and a charging current to show on the meter. If that doesn't work I would be checking for a loose connection on the wiring first before thinking of an alternator problem.

18 hours ago, chris1138 said:

First off, I was instructed to turn the ignition key off when engine starts from gentleman i bought boat off.  I was warned never to have red light on. 

 

Key should be in the run position when the engine is running, as otherwise you won't get any charging. If the red light stays on after running the engine up to half revs or more you have a problem. That could be a failed drive belt, electrical connection or alternator fault. The video shows the alternator is rotating OK, so you can rule the belt out for now. Checking connections is quicker and cheaper than removing the alternator for testing (and possible repair or replacement) so is the obvious next step.

 

19 hours ago, Tony Brooks said:

You MIGHT have left a thickish cable off the main starter connection, maybe about 6mm in diameter. That would be the main charging lead from the alternator that is using the main nut type starter terminal as a junction box, but that is in no way definite because we need to know a lot more about your system.

If it was set up that way that would suggest the ammeter is in the main positive lead from the battery to the starter motor, which sounds unlikely. Isn't it more probable that there is a wire from the alternator positive to the ammeter and from there to the battery (possibly via isolator/fuse)? And that wire has perhaps been disturbed during the installation of the new starter motor.

[chris1138]

Mike - 

Just bought a new one. 

Old one gave up the ghost over winter.

 

Tony and David-

I tried with the key turned right today. 

No joy. 

Going to check behind ammeter for loose wires this weekend.  Tbf due to the z drive not turning left I had the steering wheel off and replaced the cog thing in behind. So could have pulled something out easily. 

 

Will get back to you. For pub now. 

 

Thanks 

16 hours ago, Quattrodave said:

Hmmm rather sounds like the stern drive hasn't been looked after.  Get it out of the water and serviced properly, change seals and bellows.

 

The Enfield 130s are good sterndrives when cared for.  They are a bugger to set up properly.  If not set up properly or cared for they will eat themselves. 

Yes. 

 

I doubt I'm in the clear with the steering issue. 

But I dont think she will be out of water this year.

[Tony Brooks]

1 hour ago, David Mack said:

If it was set up that way that would suggest the ammeter is in the main positive lead from the battery to the starter motor, which sounds unlikely. Isn't it more probable that there is a wire from the alternator positive to the ammeter and from there to the battery (possibly via isolator/fuse)? And that wire has perhaps been disturbed during the installation of the new starter motor.

 

No, it is a single battery, single alternator boat. The standard way to wire that is alternator B+ > ammeter > battery connection, in this case probably the main stater connection. The feed to the rest of the electrics (engine and domestic, but not the stater motor) would come from the alternator side of the ammeter, so the ammeter will show both charge and discharge. Trouble is we do not know what has been done and how over the years.

 

The fact that he has the red light and can energise the stater suggest that the ammeter is probably OK, so once the wiring has been confirmed it will suggest the alternator needs to come off for testing.

Edited March 31, 2023 by Tony Brooks

[David Mack]

8 minutes ago, Tony Brooks said:

No, it is a single battery, single alternator boat. The standard way to wire that is alternator B+ > ammeter > battery connection, in this case probably the main stater connection.

Yes. But that means the wire from the alternator isn't directly wired the short distance from alternator to starter - it goes via the control panel, so if it then goes back to the starter that's two longer wires that could have been disturbed. The fact that the lamp lights at all suggests that it's connection to the alternator is in order, as is the negative connection back to the battery, and the field coils.

[Tony Brooks]

44 minutes ago, David Mack said:

Yes. But that means the wire from the alternator isn't directly wired the short distance from alternator to starter - it goes via the control panel, so if it then goes back to the starter that's two longer wires that could have been disturbed. The fact that the lamp lights at all suggests that it's connection to the alternator is in order, as is the negative connection back to the battery, and the field coils.

 

Those long wires are exactly why moving iron ammeters are bad news on boats.  Not only is there volt drop potential on boats with larger batteries but also the danger from the probably unfused long runs.