Starter battery voltage whilst cranking

[dmr]

4500 hours is a huge number of hours for a forklift truck engine in a narrowboat.

It is obvious that the engine is very nearly siezed solid.

happy new year 😀

[nicknorman]

Just now, dmr said:

4500 hours is a huge number of hours for a forklift truck engine in a narrowboat.

It is obvious that the engine is very nearly siezed solid.

happy new year 😀

 You are too kind!

[Sailbadthesinner]

18 minutes ago, dmr said:

4500 hours is a huge number of hours for a forklift truck engine in a narrowboat.

It is obvious that the engine is very nearly siezed solid.

happy new year 😀

 

Not seized, that would cause excess current draw by the starter motor. It's only about 300A so not seized and not a Volts drop fault in the wiring either, the Volts drop is In the battery.

 

 

 

[john.k]

Valves may be gunked up from idling or bores glazed from  light running......a continuous compression leak causes a greater draw on starter batteries.

[dmr]

10 hours ago, Sailbadthesinner said:

 

Not seized, that would cause excess current draw by the starter motor. It's only about 300A so not seized and not a Volts drop fault in the wiring either, the Volts drop is In the battery.

 

 

 

 

Do note the smiley.

Actually, if nothing goes badly wrong a high hours engine will take less starter current, engines are like people and reach a peak in their late middle age just before it all goes wrong, so as long as the compression is decent the reduction in friction from a slightly loose engine will be advantageous, but then at 4500 hours this engine is likely much less than half way through its life.

4 hours ago, john.k said:

Valves may be gunked up from idling or bores glazed from  light running......a continuous compression leak causes a greater draw on starter batteries.

 

You will have to explain that.

A loss of compression will result in lower starter current, though it might take a little more cranking duration to start the engine.

[MtB]

42 minutes ago, dmr said:

You will have to explain that.

A loss of compression will result in lower starter current, though it might take a little more cranking duration to start the engine.

 

He's in Australia. Maybe if you turn an engine upside down, the current goes UP. 

 

 

 

(Obligatory smiley, before someone comes along and starts explaining how what I said cannot be true....)

 

 

 

 

[dmr]

If its easy to prevent the engine from starting then giving it a good crank for many seconds is a useful thing to do, and might give a clue to the state of the battery. Its worth doing this at least once a year, probably at the onset of winter.

If you have an engine that starts well its possible for a battery to degenerate into very poor condition without it getting noticed.

You might possibly do this already as part of the oil change ritual.

[nicknorman]

Just now, dmr said:

If its easy to prevent the engine from starting then giving it a good crank for many seconds is a useful thing to do, and might give a clue to the state of the battery. Its worth doing this at least once a year, probably at the onset of winter.

If you have an engine that starts well its possible for a battery to degenerate into very poor condition without it getting noticed.

You might possibly do this already as part of the oil change ritual.

Yesterday It was probably cranked for a total of 30 seconds with the stop button pressed, and I then ran the engine for 30 mins or so. This morning I didn’t use the heaters and it started quickly, sounded a bit more lively and the TP didn’t brown out. So maybe the battery was just a bit lazy?

[magnetman]

There seems to be an argument for having a charging setup to the starter battery from the lithium batteries. Just to keep the forner happy in colder weather when not on sure power. 

 

Edited December 27, 2023 by magnetman
double post taken out

[nicknorman]

31 minutes ago, magnetman said:

There seems to be an argument for having a charging setup to the starter battery from the lithium batteries. Just to keep the forner happy in colder weather when not on sure power. 

 

In our case, we are either on shore power or running the engine at least every couple of days. A starter battery that is properly charged shouldn’t lose any detectable charge in 2 days.

[magnetman]

No but if it did then a little circuit enabling one to transfer some of the main battery power would not be terrible..Not a jump lead just a relatively small wire, a fuse and an isolator switch. 

Because of the voltage different LFP is a good charger for a LA battery. 

[dmr]

1 hour ago, nicknorman said:

Yesterday It was probably cranked for a total of 30 seconds with the stop button pressed, and I then ran the engine for 30 mins or so. This morning I didn’t use the heaters and it started quickly, sounded a bit more lively and the TP didn’t brown out. So maybe the battery was just a bit lazy?

 

Have you confirmed that the starter battery is getting charged reliably?

[Tony Brooks]

3 minutes ago, dmr said:

 

Have you confirmed that the starter battery is getting charged reliably?

 

He did say at the start of the process the voltage was in excess of 13 V (13.3 I think) and it quickly dropped to 12.7 V. That suggests the batery was more or less fully charged.

[dmr]

27 minutes ago, Tony Brooks said:

That is why I said "reliably", I was thinking of maybe intermittent charging, but I confess that I am not thinking clearly as Father Christmas bought me a nasty dose of covid.

I think an intermittent of partial battery short or bad (internal) interconnect is te most likely explanation and a new battery would be a good investment

He did say at the start of the process the voltage was in excess of 13 V (13.3 I think) and it quickly dropped to 12.7 V. That suggests the batery was more or less fully charged.

 

That is why I said "reliably", I was thinking of maybe intermittent charging, but I confess that I am not thinking clearly as Father Christmas bought me a nasty dose of covid.

I think an intermittent of partial battery short or bad (internal) interconnect is a possible explanation and a new battery would be a good investment.

However this explanation would require the original battery to have been knackered and the new one to be a bit defective so we are looking at a very unlikely combination of events.

A good measure of starter current would be useful.

To revisit the gloom and doom scenario......failed head gasket and a bit of water in the bores.😀

[jonathanA]

2 hours ago, dmr said:

I think an intermittent of partial battery short or bad (internal) interconnect is a possible explanation and a new battery would be a good investment.

However this explanation would require the original battery to have been knackered and the new one to be a bit defective so we are looking at a very unlikely combination of events.

Not really given 2 years between battery changes.... also if you read the thread Nick has measured the starter current.

 

So it seem like the battery should have been in a good state of charge confirmed by a voltage of 13.3v at the terminals. Drops to 8 and a bit when cranking.  It's a proported duel purpose starter/leisure battery....  so perhaps a bit of a compromise?

 

Seems to be starting better following a bit of engine use / charging. 

 

Does suggest a 'lazy' battery.... think now that's understood then its a question of whether that can be lived with... 

 

[Sailbadthesinner]

1 hour ago, jonathanA said:

Not really given 2 years between battery changes.... also if you read the thread Nick has measured the starter current.

 

So it seem like the battery should have been in a good state of charge confirmed by a voltage of 13.3v at the terminals. Drops to 8 and a bit when cranking.  It's a proported duel purpose starter/leisure battery....  so perhaps a bit of a compromise?

 

Seems to be starting better following a bit of engine use / charging. 

 

Does suggest a 'lazy' battery.... think now that's understood then its a question of whether that can be lived with... 

 

 

As I said a fair number of posts ago

😉

[nicknorman]

10 hours ago, dmr said:

 

Have you confirmed that the starter battery is getting charged reliably?

Yes. The Beta panel voltmeter is the starter battery voltage and sits over 14v when the engine is running (it can’t be read very accurately).

[magnetman]

What about when its on shore power? 

 

What type of charger is maintaining the start battery? 

[nicknorman]

2 minutes ago, magnetman said:

What about when its on shore power? 

 

What type of charger is maintaining the start battery? 

Mastervolt Combi starter battery output.

[dmr]

Been thinking about this a bit more, too bloody tired to do anything more constructive than lying in bed and thinking, If covid is this bad after 5 injections then Im really glad I did have those injections.

The cranking voltage is a bit low according to the www, but don't believe everything you read on the www. I would like to do a proper measure of mine but my data acquisition system has just thrown an expensive tantrum.

I wonder if dual purpose batteries really are somewhere between a starter and deeop cycle in terms of plate construction, or if (more likely) they are just a rebadged starter?

4500 hours is a fair bit, have you done full service recently? thinking tappets and possibly injector overhaul/replacement? Does the engine smoke at all? All the light load running is a potential source of a lot of soot and coke so maybe this, togerher with winter temperatures, has made the engine just a little less enthusiastic with its starting? and this has just tipped the travelpower over a theshold.

 

[Tony Brooks]

1 hour ago, dmr said:

wonder if dual purpose batteries really are somewhere between a starter and deeop cycle in terms of plate construction, or if (more likely) they are just a rebadged starter?

 

That was Gibbo's opinion, starters fitted with handles. Especially now many trucks demand a domestic supply ability.

[cuthound]

On 26/12/2023 at 18:18, nicknorman said:

Yes I was wondering if the starter motor could be tired. Look quite difficult to get to in our installation though!

Had a similar issue on my first shareboat. The battery was changed to no avail.

 

Then the starter motor was taken to an rotating electrical repairer, tested and found to be defective.

 

 

 

 

[Tony Brooks]

1 hour ago, cuthound said:

Had a similar issue on my first shareboat. The battery was changed to no avail.

 

Then the starter motor was taken to an rotating electrical repairer, tested and found to be defective.

 

I have two comments.

 

It is not unknown for starters with plain sintered bronze bearings to dry out and then the extra friction gives these symptoms. It was often the bearing in the drive end overhang bracket, but the Beta starter has no "overhang nose" from what I can see.

 

The other thing that happens on a four brush starter is that a brush wears out or stick so it tries to run on one pair of brushes, this reduces the torque and cranking speed so excess current flows. I suspect the Beta starter is a two brush geared unit, so this can not apply.

 

I agree it needs to be considered, but feel in this case it is less likely. As it seems to have recovered a bit I wonder if it was suffering a bad case of acid stratification until a good engine charge stired it all up.

 

 

[nicknorman]

10 hours ago, dmr said:

Been thinking about this a bit more, too bloody tired to do anything more constructive than lying in bed and thinking, If covid is this bad after 5 injections then Im really glad I did have those injections.

The cranking voltage is a bit low according to the www, but don't believe everything you read on the www. I would like to do a proper measure of mine but my data acquisition system has just thrown an expensive tantrum.

I wonder if dual purpose batteries really are somewhere between a starter and deeop cycle in terms of plate construction, or if (more likely) they are just a rebadged starter?

4500 hours is a fair bit, have you done full service recently? thinking tappets and possibly injector overhaul/replacement? Does the engine smoke at all? All the light load running is a potential source of a lot of soot and coke so maybe this, togerher with winter temperatures, has made the engine just a little less enthusiastic with its starting? and this has just tipped the travelpower over a theshold.

 

I changed the oil recently but the tappets aren’t in Beta’s maintenance schedule. I did check them in the early days but they were spot on. Yes maybe should check again but I doubt it’s the issue. The engine gives a slight puff of smoke when it is started and after that absolutely zero smoking. Oil consumption is zero too.

 

I agree with the tipped threshold theory. Travelpower working properly or not is a hard binary thing, but could arise from a slight change in battery or starter motor liveliness. ie it has a Schmitt Trigger input!