Need Yanmar tach pulse setting for Balmar alternator and 4JH4E

[hlev00]

I have a Balmar Series 60, 100A alternator with ARS-5 alternator on a Yanmar 4JH4E. It has the Balmar serpentine kit.


Since installing the kit, the tach has not been accurate, which I expected. I am finally getting around to adjusting this. The original Pulse setting was 10.29. I found an article from someone else that did the same and recommended 12.45 as the correct setting, This has gotten me closer but is still off. Looking back at the article, it is for a different Yanmar engine and pulley setup. Does anyone happen to have this same alternator + engine (probably any 4JH) + pulley set up and know what the pulse setting should be?


The next is to try the manual adjust method. VDO (tach vendor) recommends setting at above idle but I probably need three people plus a tach to do this accurately.


Thanks,
Harry


s/v Juno

[a64pilot]

You should be able to do it yourself, adjust engine RPM to midrange verifying with a phototach, then adjust tach until RPM matches, then check at full RPM and idle to confirm

[hlev00]

Originally Posted by a64pilot

You should be able to do it yourself, adjust engine RPM to midrange verifying with a phototach, then adjust tach until RPM matches, then check at full RPM and idle to confirm

I do have a phototach but not enough hands this week. I was hoping to get away with a number to set it "the easy way". Thanks for the quick response though.


Harry

[hlev00]

More hands showed up! I used an optical tach and got to where the needle is at 2000 and optical tach says 1997. The pulse setting is now 13.18 future reference. I may play a bit more but that is looking pretty good for now.

[42Possibilities]

Originally Posted by hlev00

More hands showed up! I used an optical tach and got to where the needle is at 2000 and optical tach says 1997. The pulse setting is now 13.18 future reference. I may play a bit more but that is looking pretty good for now.

I have a Yanmar 4JH4E with a Electromaax alternator and have the same issue with the Tachometer not reading correctly. I have worked out actual RPM vs tach reading with a optical tach but don’t know how to adjust the panel tach. Can you tell me how you did it?

[hlev00]

This should be self explanatory. We did the adjust method after the numbers we had didn't work. We used a small screw driver. I think an phillips #0. I would have felt better with a small wooden dowel. I practiced getting the screwdriver in the right position without the engine on so I could feel the button press because the back of our tack is behind a bulkhead that I had to do blind.



I for it working at 2000 RPM. I am going to verify at a couple of other speeds but we are so much closer that I'm not in a hurry. One suggestion from someone else is to verify with WOT. I made the mistake of not recording a few of these key RPMs before changing alternators. I've looked in the service manual but can't find the correct WOT RPM. Ours reads 3400 with no load after adjusting.


https://j109.org/docs/vdo_programmab..._hourmeter.pdf