My tach is falling to zero. It often starts out working fine when I first start up then later acts intermitantly and/or drops to zero. Sailing yesterday, that's exactly what happened and after we sailed with engine off or two hours, and started back up, it was still reading zero. Alternator seems to still be working (although only reading about 12-13 volts). tried tightening up the belt and still read zero. reving up engine still zero. I've tried turning the calibration knob on the back of the tach as has been recommended before and that didn't help. I've checked all the wire connections I can see and find no issues. This morning, started her up at the dock, planning to bypass the wiring to see if that would make it work, but it worked immediately on start up. let it idle up to temperature and it still worked, reved it and it went up appropriately. And Alternator output was reading 14 volts. (batteries at Float charge.) Help! I don't like running without knowing my engine speed.
Any help appreciated.
Sam
Capt. Sam Murphy
1994 Catalina 36, Hull 1327
Shoal draft, two cabin model.
Panama City, Florida
I was going to suggest running external wires from alternator to tach temporarily - but you have already thought of that. I would still run them and keep them that way until you can find the problem. You may also have worn out contacts on the alternator.
Haro Bayandorian, 1999 C36 MKII, Sail La Vie #1787, M35B,
Coyote Point, San Mateo, CA.
The problem might actually be your alternator. If it's not putting out what it should be I'd be looking there. 12-13 volts sounds much lower than it should be after a startup.
The tach doesn't light up until the alternator does, if there's no power on the field wire, or not enough power for some reason, the alternator is not going to put out any pulses, or enough pulses, to the tach.
14 volts is too high for float voltage by the way, should be more like 13.2-13.6.
If you've got an external reg I'd be checking that, and checking the wiring at the alternator. Makes sure the field wire is delivering enough volts.
Your alternator putting out 12-13 volts when your tach was acting up is the first place to start. Two thoughts: (A) that's a very low voltage so you might just be reading battery voltage, suggesting the alternator is not putting out which would possibly be the reason for no tach (no stator pulses). (B) some folks using an external regulator have left the tach directly connected to the stator output on the alternator. This works fine until the regulator goes into float. At that point, there might not be enough field current to produce stator pulses, so some external regulators have tach input and a tach outputs to solve this. The intention here is to connect the alternator stator output to regulator tach input, and regulator tach output to the tach. This helps the regulator provide enough field current to maintain reliable tach pulses when regulator is at float.
Nick Caballero
Retired C36/375IA Mk II Technical Editor
Nick's (b) idea is a good one. Do you have a fridge on the boat and is it running when you're motoring. Tachs will stop if the batteries are full sometimes. This happens a lot when folks are plugged in, start their engines and wonder why the tachs don't work. It's because the alternator's regulator sees no reason for the alternator to produce output.
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)
Thank you all. Those are great comments and suggestions. I was suspicious my problem is alt related already. The alt is a new (20 hours) 80amp Baldor with an external smart regulator. I've got a complete trouble shooting guide for both the alt and the regulator and I'll go through it this weekend. I'm sure your suggestions will lead me to a solution. As usual, ya'll are the greatest!
Thanks, I'll report back.
Sam
Capt. Sam Murphy
1994 Catalina 36, Hull 1327
Shoal draft, two cabin model.
Panama City, Florida
I thought I would post a closing (I Hope) note to this issue. I took in all the good suggestions and headed back down to the boat where I performed the manual's recommended diagnostics on both the Alternator and the ASR-5 regulator. Both checked out fine. So then I ran continuity checks on the regulator harness and the connection from the Regulator to the Tach. The wiring is as described by Nick above, in that the Stator out from the Alt. goes to the Reg. then a wired from the alt. out to the tach. All the continuity was good. I called Balmar. They suggested reprograming the regulator to beef up the target voltage but when I used the magnet to try to get the regulator to go into its programming mode, it wouldn't. Call again to Balmar and they had me ship the reg back while they shipped a new one. Got it in two days!! amazing!. Installed it and guess what. Tack works fine. Ran engine for half hour and it was still working but I haven't taken the boat out for a longer run, so I'm guardedly optimistic. Meantime Balmar says they will honor the warranty on the regulator even though I bought it in the fall of 2012. It had less than 35 hours. I'm very pleased with the service of Balmar. And hoping that the early failure was a fluke.
And lastly, thanks sooo much to all you smart sailors for the right-on suggestions and advice.
Sam
Capt. Sam Murphy
1994 Catalina 36, Hull 1327
Shoal draft, two cabin model.
Panama City, Florida
Great news, Sam, and thanks for letting us know.
Where is your regulator located? Outside the engine space, I trust.
I just learned something new, thanks to you: Tach not working? In addition to all the "usual suspects," try [I][U]reprogramming your external regulator[/U][/I]. If it won't work, guess what?!?
Nice of Balmar, Maine Sail has good things to say about them.
Also, interesting how sometimes a phone call can be a lot easier than emails...:eek:
Thanks again, glad you're baaack!!!!;)
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)
Thanks Stu. My regulator is mounted just behind the companion way on the bulkhead, outside the engine cover box. I think its a perfect spot for it in that its outside of the engine heat and its LED display can be read just by looking behind the stairway. I'm still a little puzzled by one issue; when I started up the engine, with batteries at 100% the regulator was telling my alternator to charge "Bulk" rate. after idling for 30 minutes it still showed Bulk when it should have gone to "Float".. They agree it should be showing "Float". (added after a conversation with Balmar): Balmar says the regulator will go immediately to Bulk rate on start up even if batteries are 100% then cycle to float after a time. It did this when I went for a longer sail, (four hours) on Sunday. Also the tach problem did not re-occur so I'm putting this one in the "solved" column. Sam
Capt. Sam Murphy
1994 Catalina 36, Hull 1327
Shoal draft, two cabin model.
Panama City, Florida