Yanmar 3-Banger Gauges Read Zero

[Sinbad51]

Check for a black reset button on the engine panel

[Sinbad51]

Can. Youpost a picture of the panel?

[Gone2long]

Originally Posted by Sinbad51

Can. Youpost a picture of the panel?

Will try to do so in the next 48 hrs or so.

There is a white button, used to start the engine once the key is inserted, pressed and turned to the right. That is when alarms go off, until the engine engages and begins running. No black button.

The engine is killed using a lift up, T shaped handle in the cockpit, which is connected by a cable to ... I am not sure where. Hard to see where the cable actually ends up.


The mechanism is like the hood mechanism to a car.

More later,

G2L

[Wotname]

Originally Posted by Gone2long

Will try to do so in the next 48 hrs or so.

There is a white button, used to start the engine once the key is inserted, pressed and turned to the right. That is when alarms go off, until the engine engages and begins running. No black button.

The engine is killed using a lift up, T shaped handle in the cockpit, which is connected by a cable to ... I am not sure where. Hard to see where the cable actually ends up.


The mechanism is like the hood mechanism to a car.

More later,

G2L

It's connected to the fuel shut lever on the injector pump. This will be near the front of the engine on the right hand side (when viewing looking from the gearbox end towards the flywheel end). It will be very close to the engine mounted fuel filter.

[Gone2long]

Originally Posted by Wotname

It's connected to the fuel shut lever on the injector pump. This will be near the front of the engine on the right hand side (when viewing looking from the gearbox end towards the flywheel end). It will be very close to the engine mounted fuel filter.

Thank you,

Will take another look. The engine space is very cramped, so I have yet to be able to get a good angle of vision.

Also, what do you think about the fact that the warning lights seem to be working? As noted above, they indicate that their is a low battery charge and low oil pressure when the key is turned. That seems normal, as in an older automobile.

Then, when the diesel engages. the warning lights, and alarm, go off and do not go on again as long as the engine is running. This would suggest that the warning lights are working and that the engine actually has sufficient, if perhaps a bit low, oil pressure and that the charging system has sufficient amps.

What think ye?

G2L

[Wotname]

Originally Posted by Gone2long

Thank you,

Will take another look.

Also, what do you think about the fact that the warning lights seem to be working. As noted above, they indicate that their is a low battery charge and low oil pressure when the key is turned. That seems normal, as in an older automobile.

Then, when the diesel engages. the warning lights, and alarm, go off. This would suggest that the warning lights are working and that the engine actually has sufficient oil pressure and the charging system has sufficient amps.

What think ye?

G2L

Yep, that's normal and proper operation.

Also tells us the original transducers (senders) on the engine are still there and are serviceable.

As someone else posted, this engine was only fitted with transducers for the warning lights (and audible alarm); it did not have transducers suitable for gauges.

So if a previous owner fitted after market gauges, then he would had to have fitted after market transducers suitable for the gauges. These should be added in addition to the original transducers. Maybe they were fitted, maybe not; maybe they are unserviceable or maybe the wiring is unserviceable or maybe the gauges themselves are unserviceable or maybe the power supply to the gauges is unserviceable.

Keep learning and keep hunting down the problem. With some perseverance, you will find out what's wrong and learn a shipload about the engine as well

Anyway, it's good news that the original transducers are still there and working properly.

And yes, some pictures will help .

[Gone2long]

Originally Posted by Wotname

Yep, that's normal and proper operation.

Also tells us the original transducers (senders) on the engine are still there and are serviceable.

As someone else posted, this engine was only fitted with transducers for the warning lights (and audible alarm); it did not have transducers suitable for gauges.

So if a previous owner fitted after market gauges, then he would had to have fitted after market transducers suitable for the gauges. These should be added in addition to the original transducers. Maybe they were fitted, maybe not; maybe they are unserviceable or maybe the wiring is unserviceable or maybe the gauges themselves are unserviceable or maybe the power supply to the gauges is unserviceable.

Keep learning and keep hunting down the problem. With some perseverance, you will find out what's wrong and learn a shipload about the engine as well

Anyway, it's good news that the original transducers are still there and working properly.

And yes, some pictures will help .

Thank you,

Your post helps greatly to clarify a couple of the critical issues. I think that the previous owner added the new gallery of gauges with the intention of adding the new transducers, but never got around to it.


This is a guess based on lots of other partial repairs which have I have inherited, and the lack of any "sender" located on the engine, which, as far as I can tell, seems anywhere near recent.

Thanks again for all your help.

G2L

[Wotname]

Originally Posted by Gone2long

Thank you,

Your post helps greatly to clarify a couple of the critical issues. I think that the previous owner added the new gallery of gauges with the intention of adding the new transducers, but never got around to it.


This is a guess based on lots of other partial repairs which have I have inherited, and the lack of any "sender" located on the engine, which, as far as I can tell, seems anywhere near recent.

Thanks again for all your help.

G2L

FWIW, additional transducers (for the gauges) are normally tee'd off at the same locations as the original alarm transducers.

The gauges themselves can be easily checked as others have noted. They usually have 3 main terminals on the back plus some for internal lights (if fitted).

One terminal is power (+ve 12 volts).
One is ground (-ve)
The other (signal) goes to the transducer

If you are not sure which is which, try to post a photo; someone here will know.

For a simple go/no go test (again as others have noted), put power and ground of the respective terminals with some temporary leads and leave the 3rd terminal unconnected. The gauge should have very little or no movement.
Now connect the 3rd terminal to the ground terminal and the gauge should give full scale deflection.

[Gone2long]

Originally Posted by Gone2long

I'm an admittedly ignorant, new owner of sailboat boasting a 20 year old Yanmar, three cylinder, 27 horse power diesel. The diesel seems to run fine, and may have been rebuilt in the past.

However, both the temperature gauge and the oil gauge read zero at start up and after running for up to half an hour. Apparently, this is an electrical problem, and may be as simple as a blown fuse or two, but I do not know where to look for such an items and what they might look like on a 12 volt system.

Any advice, photos, or links would be greatly appreciated.

Regards to all,

G2L

As per the above, I found a manual aboard for the engine, and, as suggested by some of you, the manual indicates that the original panel for the boat had only warning lights, no senders. This helps clarify the situation, and all warning systems seem to be working. Got a knocking sound, however, which I will be discussion soon, in another thread. Thanks to everyone for your help.