Warning alarm and Hour meter not working
 

After installing my new motor today and turning the key on to check the electrical system, I found the alarm and hour meter not functioning. I labeled all wires as I pulled the old motor out and can't find anything wrong. HELP! Any suggestions?

Bad senders? or your ground?

Is the hour meter directly associated with this? Which ground should I look for? I'm not that great with electrical problems! Where do i start?

is your hour meter built into the Tach? or is it seperate

My hour meter is separate

My guess is you missed a ground putting the motor back in

the hour meter is most of the time a 2 wire system, a full time ground, and a key on [ignition on} hot, which runs the meter, most hour meters will register time by leaving the key on, engine does not even have to run, pull your gauge panel and check with a test light, you might have a bad hour meter if your ground and hot are ok

My hour meter and alarm worked fine before I pulled the motor. I looked for 2 hours yesterday to find a ground wire I may have missed. Decided to have a few beers and call it quits for the day. I may look again this afternoon. By the way there is no water in the motor yet. Does the thermostat housing need water for the alarm to signal when the key is on??

I'm assuming you have carbed
merc. setup.
The alarm is activated by one of
three switches, gear oil level,
high engine temp, or low oil pressure
the alarm sounds when you turn the
key on because theres no oil pressure,
and the oil pressure switch is normally closed.
The switch is grounded to the block.( no oil pressure = ground)
Where is the hour meter mounted ?
(engine, or dash) If its in the engine area,
and the ground is missing, this would give you
symptoms you discribe.

One easy check, take a jumper cable lead,
run it from neg. battery to the engine
block, heads, etc.

Do any of the other guages move when you
turn on the ignition switch ?

Good luck on your hunt,
jt

Absolutly

Everything else works. I'm thinking it has to be a ground. Seems too coincidental for both items to go out at the same time. It has me stumped because I looked for a missed wire or ground for 2 hours and found nothing.

The hour meter is in the dash.

Did you put alot of thread sealer on the
oil pressure switch?
that could be causing a bad ground for
the alarm, remove the wire from the
oil pressure switch,(with ignition on)
touch the wire to the block, the alarm
should sound, if not, there is an open in
the ground wiring from the alarm to
the switch, or lack of positive voltage
to the alarm.

As for the hour meter, there usually set up
like Mark has said, although, I have seen
some wired to an oil pressure switch, so
the hour meter only runs when the engine is
running, this usually uses a 3 pole oil pressure
switch,
is yours like that?

My hour meter runs whenever the key is on regardless if the motor is running. I did use lots of ARP thread sealer on all fittings and senders. HMMM.......that may be it. I'll try that next. thanks

Take a digital volt meter and check you readings at the hour meter and at the alarm.....You can grab both ground and power from behind the dash right next to the gauge......check your sources first! That will tell you if your getting the right feed to the items. if Your not getting good feeds then its time to start back tracking from the gauges and alarm to where they have hookups....if both look to be hooked up porperly you can take the Meter and check the wires between the gauge/alarm and the point of contact.....does this make any sense or did i just confuse you more? :)

Wally, It makes sense. Thanks I just don't understand why everything worked fine before I pulled the motor and now????????? Is it possible that the pigtail is not snug up against all terminals? I never did tighten the hoseclamp. Maybe I should wiggle the connection and tighten clamp.

Here's one more thing to try,
with either a test light or volt meter,
ignition on, connect 1 lead to the hour
meter terminal ( it doesn't matter which terminal,
being it's not working, it's just potential energy)
and the other to battery neg., if the light comes on,
or voltmeter reads battery volts, you have your
positive source.
Next, with ignition off, connect 1 lead to battery
positive, disconnect the hour meter neg. lead,
(this will prevent possible backfeeds thru the other
keyed components)
connect the other meter/ light lead to wire that
was disconnected from hour meter,
if you have a good ground, the light will come on,
or meter will read battery volts, if not, you've
lost your ground.

I really doubt the engine harness plug would
cause you to loose your hourmeter, but,
it could be the source for your alarm problem


Use a voltmeter, if at all possible.

good luck,
post your results

I have a nice digital voltmeter, just need to learn how to use the functions. I've been building motors and such for years but have always been intimidated by electrical systems! It's supposed to warm up this weeekend, maybe by then the 6" of white **** on the cover from today's storm will be gone and I can try some of these suggestions. THANKS

The problem ended up being the low oil pressure switch on the port side of the block. I grounded the lead directly to the block and everything worked. The switch is actually a $3 auto parts store item and not the typical $@&%ing $50 mercruiser part! I fired the new motor on Sat. and went to the river yesterday to make sure of no leaks before I put the interior back together. other than a loose exhaust boot I overlooked, everything is ok. Amazingly, the gimbal housing does'nt leak. I was most concerned about that because of the fact that I have never done a gimbal ring service before! Sorry to ramble here, but thanks for the advice.

The hourmeters working now, too ?

Yes, it is I wonder if it is coincidental. I wiggled the pigtail before I tightened the hosecLAMP.