My tachometer is fluctuating up and down even when my speed is constant. Don't know if the tach is bad or if it's a wiring issue. Any ideas would be greatly appreciated.
P.S.- My service manual doesn't give any info on the tach.
My tachometer is fluctuating up and down even when my speed is constant. Don't know if the tach is bad or if it's a wiring issue. Any ideas would be greatly appreciated.
P.S.- My service manual doesn't give any info on the tach.
first off please read the rules,http://www.bbcboards.net...04651 you need to post your serial number, and model number. that said you also did not say if it is a dfi or a carb model and either can be a number of things causing the problem.
[I]TEAM CORGI DOG[I]
1996 javelin 400T /1996 Johnson 200 Venom
Sorry about the missing info. The #'s are as follows: serial GO3830172 & model MJ200TXEDC, carbed. The original 1995 tach was replaced in '04 along with a rebuilt powerhead. Tach worked fine until recently. I don't think that the engine is reving up and down as indicated by the tach because the speed is constant and the engine sound does not change when the tach jumps. This fluctuation happens in the 1000 to 4000rpm range. Again, thanks for the help.
According to your model number your motor is a 1996, if you have a volt meter you can check the tach signal at the back of the tach if your tach has posts and not just a system check plug.
Volt meter set to DC volts 12 volt scale. hook meter red lead to the sender or "S" post, hook the meter black lead to the ground or "G" post, start the motor (with water of course) and the meter should show approximately 9 volts.
If the meter shows lower than approximately 9 volts you will need to check and or replace the regulator/rectifier.
Thanks Rusty for your help. I checked the voltage at the tach & got 5.6V. I was unable to duplicate the tach jumping at least not at idle with the boat still docked. I checked all connections starting with the batt. & everything seems tight. I think I located the reg/rectifier at the rear of the engine under the power pack. Voltage is 14.5 at the batt. & drops to about 13.4 under load. Any harm in not replacing the reg/rectifier? Voltage is good! How can I tell if the reg/rectifier is the culprit?(5.6v at tach, not 9v). Thanks again for your help. Without your input I would have foolishly replaced the tach.
Rectifiers have been known to catch fire under the hood, besides not recharging the battery. JMHO I would replace it.
Thanks for the feedback. Looked up the reg/rect. on BRP website and my engine, model # MJ200TXEOC comes back as a 1995 with part# 0584641. Do I have a 96' or 95'?
Don't matter the regulator is the same for both MY's you just don't hook up the purple wire.
1995 according to this model number.
Which one is it, EO or ED?
EO, engine is a 95, my mistake, looked like an ED.
Unfortunately I have a new development with my engine. Lost spark to 3 port side cyls. I disconnected the blk/yellow shift interrupt switch but still do not have spark to those clyl. Any ideas would be greatly appreciated.
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