Gauges and ignition only work intermittantly

[nautihabits]

1992 250 Yamaha original owner. Recently, went to start and when I turned the key the gauges went blank and reset. After repeated attempts the motor finally cranked. However, while running, the gauges intermittently go blank and reset or flash different idiot lights. None of this seems to affect the running. Starting is still hit or miss. Use of the throttle trim button is also intermittent. If the gauges are not reading properly then the trim will not work but when the gauges seem to be working the trim works. I have tried bypassing the neutral cutoff and disconnected the throttle trim switch to no avail.

 

[Silvertip]

Re: Gauges and ignition only work intermittantly

Check, clean, and tighten the battery cables (both ends).

 

[nautihabits]

Re: Gauges and ignition only work intermittantly

Will do Capt.

 

[nautihabits]

Re: Gauges and ignition only work intermittantly

Could it have anything to do with using a series 24 starting battery with this motor? What is the recommended battery for a 250hp?

 

[Silvertip]

Re: Gauges and ignition only work intermittantly

Doubt it. Once running, the engine is very capable of supplying the current required for all of your electronics with sufficient left over to keep the battery topped off. You should obviously check to see that the alternator is actually working. Measure battery voltage at idle (12.6 or so) and then at about 2000 RPM (should be 13.6 or better.) If it stays at 12.6 or less regardless of engine rpm the charging system is not working.

 

[nautihabits]

Re: Gauges and ignition only work intermittantly

Cleaned and checked batteries and connections all are immaculate. Batteries have a good charge. Once battery switch is on, the trim/tilt swtch on motor works fine. Everything between the console and the motor is intermittant. Sometimes you turn the key and it starts and sometimes it doesn't. When it doesn't it kills the gauge displays and they reset. If you hold the key for a few seconds it usually starts. When it cranks it turns over strongly and fires right away. After it starts, it runs great but for the gauges flickering on and off at their leisure and the throttle trim and tilt switch working when it wants. Ignition? Wiring harness? Ground? I have checked every connection I know.

 

[rodbolt]

Re: Gauges and ignition only work intermittantly

you have a bad connection between the battey's termanals and your switch, go find it.
what is happenibg is when you turn the key to start there is a total loss of current so everything quits.
has nothing to do with your alenator or nuetral start switch and all to do with a bad wire or connection. a voltage drop test of the wires will find it in 10 min or less.

 

[nautihabits]

Re: Gauges and ignition only work intermittantly

That's why you're the Master. And congrats on that. Thanks for your time and help.

 

[nautihabits]

Re: Gauges and ignition only work intermittantly

Rodbolt - You were exactly right. Bad (RED) wire in the main wiring harness somewhere between the motor and the bilge. I found it by doing a continuity test on the wiring harness, alot of resistence on the red all others checked out. I (carefully) slit the harness insulation in the bilge and pulled out the red. Cut the red and it checked out to the console but not to the motor. I pulled a new RED 16 awg through the tube from the bilge to the motor and connected w/ heat shrink connectors and we were back in business for mini-lobster season. No more dead helm. Ran great all week. Never suspected it would be in the wiring harness itself. Thanks a bunch.

 

[rodbolt]

Re: Gauges and ignition only work intermittantly

thats why we call it trouble shooting and not poking and hopeing. take all avalible data and combine it with not only what the engine is doing but not doing as well then draw a conclusion.
glad ya found it

 

[nautihabits]

Re: Gauges and ignition only work intermittantly

I've read other posts out of curiosity trying to educate myself on other mechanical issues and knew not to second guess you guys. Others would be served well to learn that lesson. Thanks again.

 

[RoboHandJobO]

Re: Gauges and ignition only work intermittantly

After searching and reading this post, I thought I might have a similar problem. I disconnected the wiring harness at the engine and, using a multitester, checked the continuity of the wires in the harness to the helm. The red wire also tested negative as it did in this post. ?NautiHabits? slit the harness insulation and spliced in a new wire. I was also thinking about doing the same thing. Conversely, as I studied the harness connections in the motor I noticed that the red wire comes out of the harness (1). There is a quick type connector and the wire then travels up to the solenoid (2).
My question is; can I use the red quick type connector to bypass the wiring harness or should I use ?NautiHabits?? idea of slitting the harness?

 

[rodbolt]

Re: Gauges and ignition only work intermittantly

dunno, but the connection points in your picture have nothing to do with power feed to the ign switch.
rather than hijacking this thread start a new one posting your complete engine model number and the symptoms you have. looks kinda like a 3 cylinder but its hard to say.