Starting problems 2004 Yanmar 3gm30f

[Wotname]

Originally Posted by Tortuga331

I looked on Amazon for an alternator, I saw ones that said 3gm30 but not 3gm30f. Which model did you buy?

Bill

Amazon is often loose with their descriptions. There is no difference in the alternator mounting and terminals between the 3GM30 and the 3GM30F. AFAIK, the pulley sizes are the same for both engines but I don't have the parts manual nearby to confirm. I don't trust Amazon descriptions too much but presumably they will honour any discrepancies...

Do confirm the current output of what you plan to buy as there were at least 2 different alternators supplied with the 3GM30 series - 55A and 80A optional. A PO may have upgraded in the past. Physically both fit.

[NorthCoastJoe]

Simple test: At the starter solenoid there's one large cable from the batteries. A small one from the start switch/ button. With a screwdriver short between the two the starter should run. I have done this for years on many engines including my Yanmar 3 GM 30 F.

As other have said sort out the charging problem first. Auto Zone carries an alternator that works. The hard part is getting someone who can order it for you by crossing usage. It's used in a Japanese car, I forgot the model. It's best if you bring the old one with you.

[Wotname]

Stock alternator is Hitachi; the 35A model is an LR135-105; the 55A model is LR155-20. I don't have thePN of the 80A model handy.

[chris mac]

Originally Posted by Tortuga331

I looked on Amazon for an alternator, I saw ones that said 3gm30 but not 3gm30f. Which model did you buy?



Bill

The one I bought doesn't seem to be available, but this one is pretty much identical. Read the reviews, used by one with 3gm30f. Lots of similar problems with pulley size.
Mine are 2 years in now and still running well.
DB Electrical 400-44025 Alternator For Yanmar Marine 3Hm35 3Jh2 3Jh2Be 3Jh2E 3Jh3 4Jh3-Ce 4Jh3-Dte 4Jh3E 4Jh3-Te 4Lha 4Lh-Te LR155-20 LR155-20B 129772-77200 47-2136 20115006TBA LRA0124 021903640I https://a.co/d/2p3veBs
I attached the wiring diagram as it didn't come with one. it was different than my original wiring. The external ground was the problem part for me. Hopefully it helps youAttachment 277700

[Cheechako]

It's entirely possible the regulator isn't starting the alternator charging because your new batteries are full. My Yanmar 3GM30 was that way. I had to turn on some load like a refrig to get it to kick in.

[NorthCoastJoe]

The 80 amp alternator I used is API 20 107 -HO

[Tortuga331]

Originally Posted by Wotname

Yes, replace both wires as per the YouTube video upthread. I misled you in my previous post - my apologies for doing so. I had mistaken the video for a similar one where the video shows the fitting of a relay in the engine bay and leaving the existing wire in situ to operate the relay (the relay then operates the starter motor solenoid); I should have taken more attention - my bad.

Just incase,
those 2 wires I am replacing1. from the starter button to the starter
2. from the ignition to the starter

The question is: Is there room to leave the old wires INPLACE since they MAY have other functions, OR just remove them entirely to keep things clean and less complicated?

Thanks,
Bill
Tortuga

[Tortuga331]

Originally Posted by chris mac

The one I bought doesn't seem to be available, but this one is pretty much identical. Read the reviews, used by one with 3gm30f. Lots of similar problems with pulley size.
Mine are 2 years in now and still running well.
DB Electrical 400-44025 Alternator For Yanmar Marine 3Hm35 3Jh2 3Jh2Be 3Jh2E 3Jh3 4Jh3-Ce 4Jh3-Dte 4Jh3E 4Jh3-Te 4Lha 4Lh-Te LR155-20 LR155-20B 129772-77200 47-2136 20115006TBA LRA0124 021903640I https://a.co/d/2p3veBs
I attached the wiring diagram as it didn't come with one. it was different than my original wiring. The external ground was the problem part for me. Hopefully it helps youAttachment 277700

I am thinking of taking out the alternator and having it repaired, that way I don't have to worry about it fitting ,or amps or anything else.
If I could get it rebuilt within a week, I would have a part that is most likely better than all the ones on amazon.

Any thoughts one a rebuild?

Thanks everyone for your great advice!
Bill
Tortuga

[Geoff54]

Originally Posted by Tortuga331

I am thinking of taking out the alternator and having it repaired, that way I don't have to worry about it fitting ,or amps or anything else.
If I could get it rebuilt within a week, I would have a part that is most likely better than all the ones on amazon.

Any thoughts one a rebuild?

Thanks everyone for your great advice!
Bill
Tortuga

I'm late to this discussion but I would absolutely rebuild your current alternator. I had a bad experience with a DB alternator from amazon (different model to the one Chris Mac linked to) - it crapped out after less than a week. I rebuilt the old one - stator was good, cleaned up the rotor, new bearings, brushes and diode pack. A year later, it's still going strong and I expect it will last as long as it did first time round. I thought that I was saving time by getting one from amazon. Just my 2cents.

[Wotname]

Originally Posted by Tortuga331

Just incase,
those 2 wires I am replacing1. from the starter button to the starter
2. from the ignition to the starter

The question is: Is there room to leave the old wires INPLACE since they MAY have other functions, OR just remove them entirely to keep things clean and less complicated?

Thanks,
Bill
Tortuga

If the wiring is standard Yanmar, then remove them for the reasons you stated but if a previous owner has added something to the circuit, then all bets are off.

Just to be clear, make sure the wires I have highlighted in red (below) remain in place. Again assuming the wiring is stock standard.

[Wotname]

Originally Posted by Tortuga331

I am thinking of taking out the alternator and having it repaired, that way I don't have to worry about it fitting ,or amps or anything else.
If I could get it rebuilt within a week, I would have a part that is most likely better than all the ones on amazon.

Any thoughts one a rebuild?

Thanks everyone for your great advice!
Bill
Tortuga

Originally Posted by Geoff54

I'm late to this discussion but I would absolutely rebuild your current alternator. ..........

Yes, totally agree with Geoff54.

The original Hitachi unit is robust. Most likely the fault is either the internal regulator or the diode pack, less likely the brushes and remotely the bearings or windings. Regulator / diode pack / brushes / bearings are all easy to replace and any halfway decent repairer would check and replace as necessary.

I have Hitachi units that 40+ years old and still serviceable. They are dumb but tough.

The service manual gives full details for a keen DIY owner to test and replace as necessary but if you are not mechanically minded, the auto repair shop is there for you!

[Capt.Don]

Originally Posted by Wotname

Stock alternator is Hitachi; the 35A model is an LR135-105; the 55A model is LR155-20. I don't have thePN of the 80A model handy.

My Yanmar 3GM30F has a Leece Neville 70A alternator, part number 66021070, externally regulated.

[Wotname]

Thanks Capt. Don.

This is the first time I have heard of Yanmar fitting a Leece Neville externally regulated alternator to a 3GM30F ex factory but just because I haven't heard of it happening, doesn't mean it hasn't happen.

I can't find any reference to Yanmar part number (in a Yanmar publication) cross referencing to the LN part number 66021070 nor can I find any Yanmar service manual detailing the wiring of an externally regulated alternator.

Are you sure a PO didn't fit the LN unit?

[Capt.Don]

Originally Posted by Wotname

Thanks Capt. Don.

This is the first time I have heard of Yanmar fitting a Leece Neville externally regulated alternator to a 3GM30F ex factory but just because I haven't heard of it happening, doesn't mean it hasn't happen.

I can't find any reference to Yanmar part number (in a Yanmar publication) cross referencing to the LN part number 66021070 nor can I find any Yanmar service manual detailing the wiring of an externally regulated alternator.

Are you sure a PO didn't fit the LN unit?

That's what's on the boat, see picture,
Don

[Geoff54]

Originally Posted by Capt.Don

That's what's on the boat, see picture,
Don

Hi Don - Just for curiosity, what boat is this?

AFAIK, Hitachi supplies electrical components to Yanmar.... BUT Yanmar is willing to supply engines without certain components. As an example, Catalina tend to use custom instruments, rather than the Yanmar panel, This also means the the usual Yanmar temp. sender does not work properly (different resistance) and the usual instrument sender has the wrong thread for the engine, so there is a Catalina specific sender.

I wonder if your alternator might be boat manufacturer specific. Either that or I suspect a previous owner installed it.

As I said, just curious.

Geoff