Yanmar 4JH57 - Alternator

[timohara]

Hi All

Can anyone point me in the direction of a specs PDF (or something similar) for the alternator on a Yanmar 4JH57 (new engine this year). I have trawled the web and can't find anything - and the Yanmar manual is not very helpful (just says 12v - 125A).

The Alternator is made by Valeo ad is model SG10S078.

Thanks all,

Tim

[sailingabe41ds]

Hi..
The Valeo number is SG10S078 as you mentioned. If you google alternator 128990-77250 that is the Yanmar number alternator you might get your alternator and j-way enterprises has it listed. Wx7002 is another number for a different manufacturer.
Hopefully you will find what you are looking for with that info. I tried a few months ago to see if I could find a back up alternator at cheaper price and get more details and I was not too successful. Balmar has a smart ready retrofit for this alternator if you are looking for a smart regulator.

Abe

[Wotname]

I can't help directly but I am wondering which particular specs you are looking for?

[timohara]

Originally Posted by sailingabe41ds

Hi..
The Valeo number is SG10S078 as you mentioned. If you google alternator 128990-77250 that is the Yanmar number alternator you might get your alternator and j-way enterprises has it listed. Wx7002 is another number for a different manufacturer.
Hopefully you will find what you are looking for with that info. I tried a few months ago to see if I could find a back up alternator at cheaper price and get more details and I was not too successful. Balmar has a smart ready retrofit for this alternator if you are looking for a smart regulator.

Abe

Many thanks Abe

[timohara]

Originally Posted by Wotname

I can't help directly but I am wondering which particular specs you are looking for?

I am wondering if it is a new modern 'smart alternator' - as I am installing Lithium house batteries - so need to know what it's voltage output is / behaviour. Suspect it is a dump alternator - and will just pump 14.1 (ish) volts out all the time - but need to be sure.

Thanks !

[GordMay]

Yanmar External Regulation Conversion Kit for Valeo Alternator
https://shop.marinehowto.com/product...conversion-kit

[Ween]

I have the same engine. Replaced the valeo extra dumb alternator. To make it ready for lithium you need to add $180 just to make it "smart ready" then another $300 for something like a MC612 regulator. That's a lot of "lipstick on a pig". Very low quality alternator.

Might as well get a 150A 60 series Balmar or an XT 170 even better and actually get 125A of steady charging, which your Lithium will love.

[timohara]

Originally Posted by Ween

I have the same engine. Replaced the valeo extra dumb alternator. To make it ready for lithium you need to add $180 just to make it "smart ready" then another $300 for something like a MC612 regulator. That's a lot of "lipstick on a pig". Very low quality alternator.

Might as well get a 150A 60 series Balmar or an XT 170 even better and actually get 125A of steady charging, which your Lithium will love.

Thanks. The Yanmar engine data sheet says the alternator is 125A max output - is that your understanding too ?

[Ween]

Originally Posted by timohara

Thanks. The Yanmar engine data sheet says the alternator is 125A max output - is that your understanding too ?

spec is 125A - never saw more than a true 90A come out of it and that was cold, ran at around 75A (shunt data) for a while but because it is so dumb and the batteries so hungry it would overheat and often sit at <50A

[tmcdonagh]

I am in the process of switching over to LiFePO4 also. I am struggling with trying to understand how the valeo will fit into the picture on my 4JH57. Two possibilities, add a second high capacity alternator and keep the valeo to keep the FLA start battery topped off or replace the Valeo with externally regulated high capacity alternator and go with a LiFePO4 start battery. Thoughts?

[Melbourne Park]

My electrical guy says leave the start AGM battery, and connect DC-DC charger(s) downstream of the start battery.

It won't damage the start battery because it will be fully charged straight after starting the motor.

A DC-DC charger with a heat sensor on the alternator, can also cut down its demands and hence preserve the alternator.

Then again, a decent alternator makes long term sense ...

[calm waters]

Originally Posted by Ween

That's a lot of "lipstick on a pig". Very low quality alternator.

Might as well get a 150A 60 series Balmar or an XT 170 even better and actually get 125A of steady charging, which your Lithium will love.

Did this mod to my Valeo, charging the factory Exides. Lasted about 18 months! Full Balmar now.

Have to agree with Ween about Lipstick and Pigs

[Jaragua]

I have the same engine, 4JH57, but I want to change this alternator and buy a new Balmar XT.







But I don't know how the type is the same.



I have 3 types to decide.
Mounting (1-2" shaft; 3.15" saddle; 4" saddle; or Vortec mount)

One foot or double foot
Pulley type (1/2" double V; J10 serpentine; or k6 serpentine)



Can someone help me please?

[Ween]

Originally Posted by Jaragua

I have the same engine, 4JH57, but I want to change this alternator and buy a new Balmar XT.

But I don't know how the type is the same.

I have 3 types to decide.
Mounting (1-2" shaft; 3.15" saddle; 4" saddle; or Vortec mount)

One foot or double foot
Pulley type (1/2" double V; J10 serpentine; or k6 serpentine)

Can someone help me please?

XT-DF-170 or XT-CR-250 both fit

yanmar uses 3.15" dual foot

special 61-0050 K6 pulley for that engine's offset

get the kit

[Jaragua]

Originally Posted by Ween

XT-DF-170 or XT-CR-250 both fit

yanmar uses 3.15" dual foot

special 61-0050 K6 pulley for that engine's offset

get the kit

Tanks