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oregondunes
09-25-2009, 01:42 AM
1987 Johnson 225 VRO

OK....so my tach stopped working this past weekend after hitting a pretty big wake.

I tested the tach tonite by applying 12v to the terminal on the back of the tach. I can make the needle jump. Then I followed the lead wire back to the motor and the distribution block between the power packs and can make the tach needle jump from there too so I know that I dont have a broken lead.

So is my tach bad or is the CDI got a short in the tach output. The motor still runs just fine and all else is great. Ive tested the stator output and charging circuits as well and all within spec according to the factory manual.

Im gonna pick up a powered tester this week to do more tests, but thought I would toss this out there in case any of you have ran into this issue before.
racer
09-25-2009, 10:58 AM
cdi does not control tack that is controled by the regulator
oregondunes
09-25-2009, 11:09 AM
Im assuming it's the CDI that beneath the two power packs, am I right ?
flabum1017
09-25-2009, 11:10 AM
You may have a bad tach circuit in the regulator, but that usually also means the regulator or stator has a problem too. Check to make sure the system is indeed charging. If it's charging good, you can attach the tach leads to one of the yellow wires comming out of the stator. If the tach still won't work then you may have a bad tach.
flabum1017
09-25-2009, 11:12 AM
Im assuming it's the CDI that beneath the two power packs, am I right ?

The tach hooks up to the regulator.... a regulator is not a CDI. The regulator is mounted in the top of the block under the power packs.
oregondunes
09-25-2009, 11:20 AM
You may have a bad tach circuit in the regulator, but that usually also means the regulator or stator has a problem too. Check to make sure the system is indeed charging. If it's charging good, you can attach the tach leads to one of the yellow wires comming out of the stator. If the tach still won't work then you may have a bad tach.

thanks...that is what I was looking for. Ill try that tonite.

When I hooked up my $200 wiz bang battery charger, it said the the system was charging between 14.5 - 15.1 volts and 30-35 amps. My manual says it has a 35 amp charging system.
oregondunes
09-29-2009, 09:38 PM
ok, swapped the grey tach wire over to the yellow wire on the block from the stator. Tach works perfectly. Also tested at the starter the stator is putting out 13.8 volts and 32 amps with a hard draw on it.

all is well for now.