Alternator Problems

[nfo]

I have been told that my alternator ( GJF Rotating Electrics Rep Lucas A376 21012001 Batch 31697) is not giving out the correct voltage/ampage. This alternator was transferred from an old Perkins Engine (rather large Perkins Engine) but only running 1 starter, 1 leisure battery to my present Lister Engine, newly refurbished, running 1 starter, 5 leisure batteries. John the Electrical Engineer at Starline Boats Nuneaton (formerly Tony Gallimore Boats of Measham, which I may add we have had so many problems with and are still on going since leaving the boatyard) said this was more than adequate for our requirements. We seem to have a problem as it is no longer charging batteries adequately. I have been told we need to have the alternator refurbished. Can anyone advise if it is worth having this refurbished and will it be adequate to run batteries stated plus 3kw inverter. Hopefully someone can help me with this and advise if there is anyone local in the ashby/coalville/loughborough area of leicestershire who can carryout the refurbishment. I am worried that if I have to have a new alternator it may not marry up with present pully system.

 

A really fed up, ----ed off boater who has another problem since leaving the above boatyard, where all work was supposedly done.

[chris w]

Whether the alternator is man enough for the job will depend on its nominal maximum current output. The next consideration is the engine/alternator pulley ratio.eg: on my boat I have twin "80Amp" alternators. However, owing to the 2:1 pulley ratio ( a very common ratio on a lot of boats) the most I will get out of a single alternator is around 70% of this or about 55 amps.

 

If the alternator needs refurbishing then the likely culprit would only be the regulator/brush assembly which is about £10 off Ebay. The next likely culprit is the rectifier which is about £15 off Ebay. This will give you an idea at least as to whether the boatyard is screwing you when they tell you its going to cost £150!!!!! A brand-new alternator is about that price.

 

What voltage is the alternator giving out?

 

Chris

[nfo]

Whether the alternator is man enough for the job will depend on its nominal maximum current output. The next consideration is the engine/alternator pulley ratio.eg: on my boat I have twin "80Amp" alternators. However, owing to the 2:1 pulley ratio ( a very common ratio on a lot of boats) the most I will get out of a single alternator is around 70% of this or about 55 amps.

 

If the alternator needs refurbishing then the likely culprit would only be the regulator/brush assembly which is about £10 off Ebay. The next likely culprit is the rectifier which is about £15 off Ebay. This will give you an idea at least as to whether the boatyard is screwing you when they tell you its going to cost £150!!!!! A brand-new alternator is about that price.

 

What voltage is the alternator giving out?

 

Chris

Hi Chris

 

Thank you for your response.

 

The alternator is giving out about 11.8 on higher revs than idle. I have given all the details which appear on the alternator but I have no idea what the output of it should be.

 

We have been screwed by the boatyard that much we have very little faith left. We are hoping that we can find someone who is honest locally to test and if need be refurbish the alternator.

[Sir Nibble]

nfo, your alternator is not making 11.8V, it is making nothing, you are reading the battery voltage (and it's very flat). The numbers you quote almost all mean nothing except to the last bloke to refurbish it (GJF Rotating Electrics at a guess), except by "Rep Lucas A376" I suspect they mean "Replaces lucas LRA376". LRA 376 is a 55A alternator and may be one of several makes, fortunately, one of those is the dear A127 and you should be able to get a bolt on replacement cheaply, and easily uprate to 65A at the same time. Chris has bought 1 or 2 from ebay and will doubtless be back in a moment to tell us how much.

Now, is your alternator knackered? How does the warning light behave? could you please measure the voltage at the D+ terminal (engine running).

[Justme]

Plenty of alternator repair places in Leicester.

 

From memory & if they are still there

 

Just off the roundabout near the newish ASDA in Thurmaston, head to wards syston, first entry on left (Britania Road) & first entry on left again.

or

Behind the firestation on hastings road in one of the industrial units.

or

Greens on Victoria road east

 

 

Justme

[chris w]

You can get A127 alternators off Ebay any day of the week. Prices vary between about £40 and £70. I was lucky enough to get a 70A version for £40 including a spare regulator and the belt pulley.

 

Chris

[Chris Pink]

I have been told that my alternator ( GJF Rotating Electrics Rep Lucas A376 21012001 Batch 31697) is not giving out the correct voltage/ampage. This alternator was transferred from an old Perkins Engine (rather large Perkins Engine) but only running 1 starter, 1 leisure battery to my present Lister Engine, newly refurbished, running 1 starter, 5 leisure batteries.

 

 

Worth noting that a A127 -alike on a small pulley on a Lister will need quite high revs before the light goes out and it starts charging.

[alan_fincher]

You can get A127 alternators off Ebay any day of the week. Prices vary between about £40 and £70. I was lucky enough to get a 70A version for £40 including a spare regulator and the belt pulley.

Yes we bought a brand new A127 70 amp model off eBay at under £40 - £38ish, I think. That had no pulley, which was an extra fiver to get fitted at a local car electrics place.

 

Worth noting that a A127 -alike on a small pulley on a Lister will need quite high revs before the light goes out and it starts charging.

 

Must depend to some degree what Lister, surely ? I don't think that's beem stated, has it ? Newer water cooled ones will tick over, and generally be run, a lot faster than the old SR series ones, for example.

[chris w]

Worth noting that a A127 -alike on a small pulley on a Lister will need quite high revs before the light goes out and it starts charging.

Not so...................one can increase the "excitation" current simply by wiring a resistor in parallel with the charge lamp. A 47 ohm/10W resistor (Maplins)would be a good starting value. If that doesn't do it (it should), connect 2 x 47 ohm/10W resistors in parallel.

 

Chris

[nfo]

Yes we bought a brand new A127 70 amp model off eBay at under £40 - £38ish, I think. That had no pulley, which was an extra fiver to get fitted at a local car electrics place.

 

 

 

Must depend to some degree what Lister, surely ? I don't think that's beem stated, has it ? Newer water cooled ones will tick over, and generally be run, a lot faster than the old SR series ones, for example.

 

Thank you for your input. We have a Lister Petter LPWS-3 canal star engine

[alan_fincher]

Thank you for your input. We have a Lister Petter LPWS-3 canal star engine

In which case I don't think comments about a slow revving Lister really apply. I'd have thought that was more for the SR or SL series, or something even older.

[nfo]

nfo, your alternator is not making 11.8V, it is making nothing, you are reading the battery voltage (and it's very flat). The numbers you quote almost all mean nothing except to the last bloke to refurbish it (GJF Rotating Electrics at a guess), except by "Rep Lucas A376" I suspect they mean "Replaces lucas LRA376". LRA 376 is a 55A alternator and may be one of several makes, fortunately, one of those is the dear A127 and you should be able to get a bolt on replacement cheaply, and easily uprate to 65A at the same time. Chris has bought 1 or 2 from ebay and will doubtless be back in a moment to tell us how much.

Now, is your alternator knackered? How does the warning light behave? could you please measure the voltage at the D+ terminal (engine running).

Thank you for your kind assistance We purchased on Ebay an A127 uprated to 70A it arrived in just 2 days and fortunately it bolted straight on. It is working perfectly. A Really relieved and pleased boater. Thank you again.

 

You can get A127 alternators off Ebay any day of the week. Prices vary between about £40 and £70. I was lucky enough to get a 70A version for £40 including a spare regulator and the belt pulley.

 

Chris

Thank you for your kind assistance We purchased on Ebay an A127 uprated to 70A it arrived in just 2 days and fortunately it bolted straight on. It is working perfectly. A Really relieved and pleased boater. Thank you again. Regards Nigel

 

In which case I don't think comments about a slow revving Lister really apply. I'd have thought that was more for the SR or SL series, or something even older.

Thank you for your kind assistance We purchased on Ebay an A127 uprated to 70A it arrived in just 2 days and fortunately it bolted straight on. It is working perfectly. A Really relieved and pleased boater. Thank you again. Regards Nigel