Travel Power

[nicknorman]

38 minutes ago, IanD said:

 

Yes you're correct about the loading, I was only looking at maximum power (e.g. for battery charging via the Quattro) not actual AC load power delivered (e.g. 2kW to a washer)... 🙂 

 

If "it goes below 800 with the 2kW load on", isn't this against Beta advice not to run with heavy charging loads below 1200rpm (e.g. 850rpm as you said)?

 

Even if the TP is only delivering 1kW, together with 75A from the alternator (~900W output?) that's a pretty heavy load, drawing something like 3.5kW/4.5hp from the engine allowing for efficiencies.

Well it’s not ideal, but there doesn’t seem to be an alternative unless we simply don’t use the tumble drier whilst cruising and have to run it and the engine whilst moored for a hour or so. My feeling is that sharing the load between the 2 alternators which are on opposite sides of the crank, and roughly halving the load on each belt and having the torque pulses from the alternators out of phase with each other, hopefully reduces the problem.

 

The low rpm is only whilst passing moored boats and we wouldn’t for example run the tumble drier when doing locks. So hopefully it can tolerate 30 secs or so at 850 rpm from time to time, and we do have the later crank which was supposed to eliminate the problem (but actually only reduces it) and the Iskra pulley sticks less far out than the TP one

[IanD]

3 minutes ago, nicknorman said:

Well it’s not ideal, but there doesn’t seem to be an alternative unless we simply don’t use the tumble drier whilst cruising and have to run it and the engine whilst moored for a hour or so. My feeling is that sharing the load between the 2 alternators which are on opposite sides of the crank, and roughly halving the load on each belt and having the torque pulses from the alternators out of phase with each other, hopefully reduces the problem.

 

The low rpm is only whilst passing moored boats and we wouldn’t for example run the tumble drier when doing locks. So hopefully it can tolerate 30 secs or so at 850 rpm from time to time, and we do have the later crank which was supposed to eliminate the problem (but actually only reduces it) and the Iskra pulley sticks less far out than the TP one

 

The later crank with splined power take-off does greatly reduce the chance of the pulley coming loose and destroying the crankshaft, but if this was the only problem why keep the 1200rpm restriction? -- which is now printed in big CAPITAL LETTERS in the manual, and I believe on a similar sticker in the engine bay.

 

When I was talking to Beta about this I wondered whether the reason was actually a crankshaft torsional resonance between the heavy flywheel at one end and the big pulley at the other, which would certainly not do the drive plate/torsional damper any good even if it didn't cause any crank damage. Unsurprisingly they would not confirm or deny this... 😉 

[nicknorman]

1 hour ago, IanD said:

 

The later crank with splined power take-off does greatly reduce the chance of the pulley coming loose and destroying the crankshaft, but if this was the only problem why keep the 1200rpm restriction? -- which is now printed in big CAPITAL LETTERS in the manual, and I believe on a similar sticker in the engine bay.

 

When I was talking to Beta about this I wondered whether the reason was actually a crankshaft torsional resonance between the heavy flywheel at one end and the big pulley at the other, which would certainly not do the drive plate/torsional damper any good even if it didn't cause any crank damage. Unsurprisingly they would not confirm or deny this... 😉 

I am aware of another Hudson boat built around the time of ours, with the same engine and new style crank and TP, that suffered the crank / pulley destruction thing a few years ago. So the problem is certainly not eliminated. But it is not a binary thing and so I try to minimise, but not eliminate, exposure to the triggering conditions.

 

On the subject of torsional resonances, our glider tug has a hollow crankshaft end, and with the current wooden propeller there is no problem. But in the interests of improving takeoff performance we are shortly to change to an aluminium propeller, and this introduces an “avoid continuous operation between 2150 and 2350rpm” restriction. Failure to adhere to this limitation can result in the propeller blade tips breaking off, which is not a good look for an aeroplane. All about the torsional resonance of the crank and the heavier metal prop.

 

A couple of years ago, we hired a Supercub with the same engine and prop combination, and you could strongly feel the vibration in that rpm “avoid band”.

Edited March 11 by nicknorman

[IanD]

19 minutes ago, nicknorman said:

I am aware of another Hudson boat built around the time of ours, with the same engine and new style crank and TP, that suffered the crank / pulley destruction thing a few years ago. So the problem is certainly not eliminated. But it is not a binary thing and so I try to minimise, but not eliminate, exposure to the triggering conditions.

 

On the subject of torsional resonances, our glider tug has a hollow crankshaft end, and with the current wooden propeller there is no problem. But in the interests of improving takeoff performance we are shortly to change to an aluminium propeller, and this introduces an “avoid continuous operation between 2150 and 2350rpm” restriction. Failure to adhere to this limitation can result in the propeller blade tips breaking off, which is not a good look for an aeroplane. All about the torsional resonance of the crank and the heavier metal prop.

 

A couple of years ago, we hired a Supercub with the same engine and prop combination, and you could strongly feel the vibration in that rpm “avoid band”.

 

Is that the one discussed some time back, where it seemed likely that the owner had done a lot of charging below 1200rpm?

 

If so, then the problem *has* been eliminated so long as you follow the advice in the engine manual and on the engine bay sticker.

 

If you don't and suffer engine damage as a result, I'd say the blame lies with the user, not Beta.

 

Of course in an ideal world the engine would be completely idiot-proof and there wouldn't be the need for any "don't do this" precautions (like with the plane you mentioned), but meanwhile in the real world... 😉 

 

(yes I have one of these T-shirts...)

Edited March 11 by IanD

[nicknorman]

53 minutes ago, IanD said:

 

Is that the one discussed some time back, where it seemed likely that the owner had done a lot of charging below 1200rpm?

 

If so, then the problem *has* been eliminated so long as you follow the advice in the engine manual and on the engine bay sticker.

 

If you don't and suffer engine damage as a result, I'd say the blame lies with the user, not Beta.

 

Of course in an ideal world the engine would be completely idiot-proof and there wouldn't be the need for any "don't do this" precautions (like with the plane you mentioned), but meanwhile in the real world... 😉 

 

(yes I have one of these T-shirts...)

 

Not sure what was discussed earlier, I don't think the owner frequents this forum. Anyway I rather disagree. Something that is a consumer product like a leisure boat engine, should be fairly foolproof. For example, we wouldn't be too impressed if we bought a car and then read in the manual "please avoid driving between 45 and 48mph as otherwise a torsional resonance in the transmission might cause the wheels to fall off".

 

[Tonka]

2 minutes ago, nicknorman said:

 

Not sure what was discussed earlier, I don't think the owner frequents this forum. Anyway I rather disagree. Something that is a consumer product like a leisure boat engine, should be fairly foolproof. For example, we wouldn't be too impressed if we bought a car and then read in the manual "please avoid driving between 45 and 48mph as otherwise a torsional resonance in the transmission might cause the wheels to fall off".

 

Especially as the Travelpower is an add on to the engine. If the engine is not upto it why did Beta add the Travelpower 

[nicknorman]

1 minute ago, Tonka said:

Especially as the Travelpower is an add on to the engine. If the engine is not upto it why did Beta add the Travelpower 

 

Well I think the answer to that is that Beta did not realise that the engine was not up to it, until bits started falling off a few years later! Same with the propeller I mentioned, when it first came out (1960s) after a few years, bits of propeller started falling off and eventually they worked out why, and issued an instruction to avoid the resonant rpm. Being American, they never bother to address the underlying issue so here we are 60 or so years later and it is still the same engine and the same propeller with the same issues! And Trump wonders why people tend not to import American stuff if they can avoid it!

[IanD]

27 minutes ago, nicknorman said:

 

Not sure what was discussed earlier, I don't think the owner frequents this forum. Anyway I rather disagree. Something that is a consumer product like a leisure boat engine, should be fairly foolproof. For example, we wouldn't be too impressed if we bought a car and then read in the manual "please avoid driving between 45 and 48mph as otherwise a torsional resonance in the transmission might cause the wheels to fall off".

 

Like I said, in an ideal world an engine would be idiot-proof.

 

In the real world, if you take a manual car and drive at at full throttle at too-low revs all the time, it'll kill the engine in short order. And if you run a Beta (modern Greenline) engine below 1200rpm under heavy load for long periods, the same might happen. It's not an engine custom-designed for boats, it's an adapted Japanese digger engine which is very durable and reliable but has a known weakness, possibly (I'm speculating here) cause by the marinising changes e.g. extra-heavy flywheel to get smooth running (from their publicity blurb).

 

If you're so mechanically insensitive as to want to be able to do this (or can't read), buy a different engine... 😉 

Edited March 11 by IanD

[Tonka]

1 minute ago, IanD said:

Like I said, in an ideal world an engine would be idiot-proof.

 

In the real world, if you take a manual car and drive at at full throttle at too-low revs all the time, it'll kill the engine in short order. And if you run a Beta engine below 1200rpm under heavy load for long periods, the same might happen. It's not an engine custom-designed for boats, it's an adapted Japanese digger engine which is very durable and reliable but has a known weakness, possibly (I'm speculating here) cause by the marinising changes e.g. extra-heavy flywheel to get smooth running (from their publicity blurb).

 

If you're so mechanically insensitive as to want to be able to do this, buy a different engine... 😉 

Can you edit your script as it is not true. You can run a Beta engine below 1200rpm with a heavy load for long periods. My Beta Bd3 sits 95% of its working life below 1200 rpm

[IanD]

13 minutes ago, nicknorman said:

 

Well I think the answer to that is that Beta did not realise that the engine was not up to it, until bits started falling off a few years later! Same with the propeller I mentioned, when it first came out (1960s) after a few years, bits of propeller started falling off and eventually they worked out why, and issued an instruction to avoid the resonant rpm. Being American, they never bother to address the underlying issue so here we are 60 or so years later and it is still the same engine and the same propeller with the same issues! And Trump wonders why people tend not to import American stuff if they can avoid it!

 

That's very likely what happened; Beta then did what they could to help with the problem (going back to splined drive) but it seems there's still a basic problem they can't fix -- at least without a major mechanical redesign, which simply isn't going to happen. Or maybe removing all the big alternator/Travelpower options, ditto. So they tell users to stay away from the problem operating region by only doing continuous heavy charging above 1200rpm. What's the alternative -- withdraw from the market?

 

The Beta Greenline engines do have a reputation for being reliable and durable, with this one known weak point -- which they clearly warn customers about... 😞 

 

4 minutes ago, Tonka said:

Can you edit your script as it is not true. You can run a Beta engine below 1200rpm with a heavy load for long periods. My Beta Bd3 sits 95% of its working life below 1200 rpm

Done -- I'm sure everyone apart from you knows which Beta engine series I was talking about... 😉

 

Your BD3 is not "an adapted Japanese digger engine" like the others though, is it? 🙂 

Edited March 11 by IanD

[Tonka]

17 minutes ago, IanD said:

 

That's very likely what happened; Beta then did what they could to help with the problem (going back to splined drive) but it seems there's still a basic problem they can't fix -- at least without a major mechanical redesign, which simply isn't going to happen. Or maybe removing all the big alternator/Travelpower options, ditto. So they tell users to stay away from the problem operating region by only doing continuous heavy charging above 1200rpm. What's the alternative -- withdraw from the market?

 

The Beta Greenline engines do have a reputation for being reliable and durable, with this one known weak point -- which they clearly warn customers about... 😞 

 

Done -- I'm sure everyone apart from you knows which Beta engine series I was talking about... 😉

 

Your BD3 is not "an adapted Japanese digger engine" like the others though, is it? 🙂 

It is a Ford Tractor engine.

I was thinking of new people who may read your post and not know which Beta

 

[nicknorman]

23 minutes ago, IanD said:

Like I said, in an ideal world an engine would be idiot-proof.

 

In the real world, if you take a manual car and drive at at full throttle at too-low revs all the time, it'll kill the engine in short order. And if you run a Beta (modern Greenline) engine below 1200rpm under heavy load for long periods, the same might happen. It's not an engine custom-designed for boats, it's an adapted Japanese digger engine which is very durable and reliable but has a known weakness, possibly (I'm speculating here) cause by the marinising changes e.g. extra-heavy flywheel to get smooth running (from their publicity blurb).

 

If you're so mechanically insensitive as to want to be able to do this (or can't read), buy a different engine... 😉 

Well a couple of things there firstly nothing wrong with running the Beta Greenline below 1200 rpm under heavy load, PROVIDED the load is not via the offset pulley at the front of the engine.

And secondly modern cars have “fly by wire” throttles and the ECU mapping doesn’t allow damaging amounts of actual throttle (as opposed to accelerator pedal position) at low rpm.

[IanD]

9 minutes ago, nicknorman said:

Well a couple of things there firstly nothing wrong with running the Beta Greenline below 1200 rpm under heavy load, PROVIDED the load is not via the offset pulley at the front of the engine.

And secondly modern cars have “fly by wire” throttles and the ECU mapping doesn’t allow damaging amounts of actual throttle (as opposed to accelerator pedal position) at low rpm.

I meant heavy alternator/Travelpower charging load, as I'm sure you're well aware because I've said it several times in this thread, and others on the same subject.

 

I was of course referring to cars with engines with similar old-school non-ECU technology to boat diesels -- as I'm sure you know perfectly well too... 😉 

 

14 minutes ago, Tonka said:

It is a Ford Tractor engine.

I was thinking of new people who may read your post and not know which Beta

 

Understood -- though since the BD3 (now obsolete) is probably outnumbered 100:1 by the various Greenline engines like the Beta 43, not something likely to be of concern to the vast majority of them... 😉 

Edited March 11 by IanD

[nicknorman]

2 hours ago, IanD said:

I meant heavy alternator/Travelpower charging load, as I'm sure you're well aware because I've said it several times in this thread, and others on the same subject.

 

I was of course referring to cars with engines with similar old-school non-ECU technology to boat diesels -- as I'm sure you know perfectly well too... 😉 

 

Understood -- though since the BD3 (now obsolete) is probably outnumbered 100:1 by the various Greenline engines like the Beta 43, not something likely to be of concern to the vast majority of them... 😉 

I’m only aware of what you write, not what you meant to write.

[IanD]

12 hours ago, nicknorman said:

I’m only aware of what you write, not what you meant to write.

Alternatively you could use your common sense to interpret what is written instead of deliberately misunderstanding it so you can have a dig... 😉

[nicknorman]

26 minutes ago, IanD said:

Alternatively you could use your common sense to interpret what is written instead of deliberately misunderstanding it so you can have a dig... 😉

There is a phrase about assumption being the mother of something. Anyway don’t be so touchy, I was not having a dig I was merely clarifying your misinterpretable writing to avoid other people being misled. It’s not all about you.

[IanD]

47 minutes ago, nicknorman said:

There is a phrase about assumption being the mother of something. Anyway don’t be so touchy, I was not having a dig I was merely clarifying your misinterpretable writing to avoid other people being misled. It’s not all about you.

It is all about you though, it seems... 😞 

 

Having a misinterpretation dig at me when that's exactly what your own postings prompted is a bit rich -- what's sauce for the goose... 😉 

 

Perhaps instead of pointless bickering and personal attacks, we could go back to making relevant and informative posts on the thread subject? 🙂 

Edited March 12 by IanD

[nicknorman]

12 minutes ago, IanD said:

It is all about you though, it seems... 😞 

 

Having a misinterpretation dig at me when that's exactly what your own postings prompted is a bit rich -- what's sauce for the goose... 😉 

 

Perhaps instead of pointless bickering and personal attacks, we could go back to making relevant and informative posts on the thread subject? 🙂 

Yes, it’s a shame you derailed the thread. But it is to some extent about me because I do actually have an affected engine and a Travelpower, whereas you have neither.

[IanD]

8 minutes ago, nicknorman said:

Yes, it’s a shame you derailed the thread. But it is to some extent about me because I do actually have an affected engine and a Travelpower, whereas you have neither.

Perhaps instead of pointless bickering and personal attacks, we could go back to making relevant and informative posts on the thread subject? 🙂 

[Deep]

Being the owner of a black box travel power I do have an interest in this. Please could someone explain the phrase “heavy alternator/Travelpower charging load”?  My assumption is that you mean if you run it close to its maximum capacity at low revs this is not wise, whilst if you say run it at below a quarter capacity at low revs this is fine.

[IanD]

14 minutes ago, Deep said:

Being the owner of a black box travel power I do have an interest in this. Please could someone explain the phrase “heavy alternator/Travelpower charging load”?  My assumption is that you mean if you run it close to its maximum capacity at low revs this is not wise, whilst if you say run it at below a quarter capacity at low revs this is fine.

Assuming you have a Beta Marine engine (which this is referring to), this is what the manual says. Running for shorter times or at lower loads below 1200rpm is OK (as @nicknorman said), the engine is not going to instantly self-destruct, but there are no hard-and-fast guidelines for this -- a bit like the CCing rules... 😉 

 

Edited March 12 by IanD

[Deep]

Yes it is a Beta so no difference between light and heavy loads, thanks.

[nicknorman]

11 minutes ago, Deep said:

Yes it is a Beta so no difference between light and heavy loads, thanks.

No I would say there definitely is a difference between light and heavy loads. But it’s not something we or a manufacturer could realistically quantify precisely. But if you are charging lead acid and the current has fallen off considerably, I’d be happy to charge at idle. If you are running a couple of hundred watts from the Travelpower, ditto. But once you go over about 500w for a significant length of time I would definitely be increasing the rpm. By 2kw I’d want to be at 1300rpm.

Edited March 12 by nicknorman

[IanD]

34 minutes ago, nicknorman said:

No I would say there definitely is a difference between light and heavy loads. But it’s not something we or a manufacturer could realistically quantify precisely. But if you are charging lead acid and the current has fallen off considerably, I’d be happy to charge at idle. If you are running a couple of hundred watts from the Travelpower, ditto. But once you go over about 500w for a significant length of time I would definitely be increasing the rpm. By 2kw I’d want to be at 1300rpm.

 

I talked to Beta in detail about this when I was looking at specifying a massive-alternator diesel boat -- like the "Powerstation" they promoted for a bit (Electrodyne 5kW alternator), or the Balmar 48V 100A alternator, or two 24V 100A alternators. In all these cases (4kW output or more) they were happy with 1200rpm minimum under load, this is about half the rated torque of the Beta 43 (the smallest engine that they fit the big alternators/Travelpower/polyvee pulleys to). The single alternators did need extra-large-diameter/width polyvee pulleys though to reduce to belt tension and side load (the dual 2.4V 100A alternators have a smaller polyvee pulley each)

 

They even said the 9kW Integrel "super-alternator" was OK at these rpms, though this needs an extra-big-extra-wide polyvee pulley and a sprung idler wheel to maintain belt tension and give >225 degree belt wrap -- and the Beta 43 would struggle a bit at these loads, the Beta 50 or bigger was preferred...

 

All of which suggests that the 1200rpm stated in the Beta manual is fine -- though a bit higher rpm certainly isn't a bad idea... 🙂 

Edited March 12 by IanD

[nicknorman]

37 minutes ago, IanD said:

 

I talked to Beta in detail about this when I was looking at specifying a massive-alternator diesel boat -- like the "Powerstation" they promoted for a bit (Electrodyne 5kW alternator), or the Balmar 48V 100A alternator, or two 24V 100A alternators. In all these cases (4kW output or more) they were happy with 1200rpm minimum under load, this is about half the rated torque of the Beta 43 (the smallest engine that they fit the big alternators/Travelpower/polyvee pulleys to). The single alternators did need extra-large-diameter/width polyvee pulleys though to reduce to belt tension and side load (the dual 2.4V 100A alternators have a smaller polyvee pulley each)

 

They even said the 9kW Integrel "super-alternator" was OK at these rpms, though this needs an extra-big-extra-wide polyvee pulley and a sprung idler wheel to maintain belt tension and give >225 degree belt wrap -- and the Beta 43 would struggle a bit at these loads, the Beta 50 or bigger was preferred...

 

All of which suggests that the 1200rpm stated in the Beta manual is fine -- though a bit higher rpm certainly isn't a bad idea... 🙂 

Yes. 1300 is what we cruise at on most canals which is why I mentioned it, but no doubt 1200 would be fine.