1989 DT150 Tach and Gauge Issues

[paul40269]

New member here, thanks for having me. I have an 89' DT150 Super Six on my Ranger bass boat. Since I bought the boat the tach, trim, speedo, and fuel gauges don't work. The only gauge that works is the oil level/water temp gauge.

I've been wracking my brain to try and at least get the tach functioning. So far I have tried:

Buying a new tach (did not work, back to Walmart it went)

Replacing the Rectifier (did not work)

Should I be looking at the stator? Is there a fuse I might be missing?

Is there a master ground in addition to the black ground wire going to the gauge?


Any help would be appreciated.

[Solarman]

Is this the fuel injected dt 150, or the carb 150 (super six, I'm guessing carb version)?

Did/do you have the service manual for this motor? If not, you should have it. Following the wiring diagram from the tach back to the motor could help you locate any wiring problem, or if you have a tach control module, or if the wiring goes directly into the control module.

I would check all connections at back of all your guages. If wiring is dirty/connections poor, this can cause these problems. Also, all the connectors at the motor, any that show signs of corrosion, poor continuity, need to be cleaned.

If you can access the back of your tach, there should be a rubber plug(?) Inside that hole is a switch (notice what position it is in before turning (take a pic of need be). Rotate the switch through the several positions a few times, then put it back to its original position.

The speedo is probably run from water pressure? Which most probably is clogged at the pickup mounted at back of boat, or if using pickup on outboard, possibly there. Those small holes easily clog up. Make sure the water tubing is in good condition, before clearing blockage, don't need water leaking into boat if damaged.

Your tach wiring is part of the wiring harness that goes back to the motor. The conditions of your wiring under your console (back of guages), and all connectors from the guages to the motor, etc. have to be clean, and dry. Otherwise, you can expect other electrical problems.

Good luck, post back when able to let us know how it's going, and what you find out.

[paul40269]

Thanks for your response. I have the carbed Supersix. I don't have the manual. Where can I get one? The old flasher on my dash is not hooked up so I'm wondering if it's a case of other gauge connections knocking out the tach, like you said. Hopefully I will catch a stretch of warm days to work on it more.

[Solarman]

Above in "puchase Suzuki parts", shown in red, search for service manuals. You might have to call boats.net to order the right one?

Or, at browns point marine go to this page...


https://www.brownspoint.com/store/pc...l-73p63820.htm

Good luck.

[paul40269]

I have this manual I found on the internet, does it look familiar?

[Solarman]

If the manual has the correct, readable, wiring schematic for your motor, it would be good to use it.

You can look up wiring for guages? Maybe it will show something you can use, maybe tests you can use to check your system??

Good luck, post back when able to let us know how it's going, and if you find anything.