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2007 Honda BF50

n_azuma

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I'm replacing the Tach for my 2007 Honda BF50 with a Honda 37250-ZV5-950AH made by Faria. Should I get the resistor assembly or will it work without it? Did I get the right Tach? My boat is a 1999 Bass Tracker 175 Pro with original gauges and it came with a Mercury outboard. I got the Honda outboard a year ago. I have been blowing the 10amp fuse on my outboard and I think it is a bad Tach. When the gauges are unplugged, the fuse does not blow.
 
If the tach that you used for the Mercury worked (set to the right setting), then the Faria should work. The setting should be on #1.

The 50's 2005 and earlier have had the issues with the tach but some of the later models do to...in spite of what is said.

I have seen some of these in the 2006/2007 not work well with the faria tach. You will just have to try it and see. I would not worry about the resistor until you try it. Unfortunately, if it needs the resistor, it probably will not make this tach work right. No one can explain why (from Honda orFaria), but the resistor only seems to work effectively if it is in conjunction with the Faria tach with an hour meter built in.

Do the other gauges work ok with the existing tach disconnected? If the fuse still blows, it is not the tach that is blowing the fuse.

Mike
 
Thanks Mike,

I plan to replace the Tach Saturday and test it on Sunday. Since the Tach came with bullet connectors I will be able to disconnect the Tach, if it continues to blow the fuse. This way I can see if it maybe one of the others (speedometer, voltage or fuel) is causing the problem. If it works the speedometer is next, its 5 to 10 mph off from my GPS.

Neil
 
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Once you remove the old tach from the circuit, put the fuse in and check out the operation of the other gauges.

If you do not blow a fuse, then you are right on about the tach.

If there is still an issue and if the gauges have blown the fuse since the Honda was installed, you need to check the overall wiring of the guages.

If you still have the Mercury trim gauge installed and connected, it will not work with the Honda (it is looking for different voltages). It may be a part of the problem.

The gauge wiring on most Trackers that I have seen goes through a larger connector, then to the Mercury or boat wiring harness. If the Honda was rigged right, you can leave the existing gauges wired together (normally looped from gauge to gauge). There are three main wires that you will need that come from the gauges to the wiring harness connector.....black, purple, and gray. There may also be a blue wiring going through the connector. That would normally be for the gauge lights. Sometimes they are wired to the nav light switch (so they come on when the nav lights are one), sometimes they are wired (jumpered) to the purple lead (ignition power). If they are jumpered, the gauge lights come on when the key switch is turned on.

There will also be another wire coming from the trim meter, if you have one. I will leave that out for now.

If the Tracker wiring was removed and a Honda wiring harness was used to each gauge, then disregard what I am about to say.

Disregard the gauge light wire and the wire for the trim switch for now....
The purple,grey and black coming from the gauges should be cut near the wiring harness connector so that any connection to them from the Honda will not feed back into anything else in the boat wiring harness. If they are still going through the connector and the Honda harness is tapped into the wiring...that is not good and you may have found your problem.

In the Honda key switch harness, there are 5 different individual leads with bullet connectors. (black, black/yellow, gray, yellow/blue, and light green/black)

It is easy to confuse what colors go where, since Honda uses a black/yellow lead for switched power (easily confused with black) If the black yellow is connected to a black lead, then your fuse will blow.

Back to the three wires...
The black from the gauges goes to the black in the Honda harness.
The purple from the gauges goes to the black/yellow in the Honda harness
The grey from the gauges goes to the grey in the Honda harness.

The yellow/blue lead in the Honda harness normally goes to the trim gauge.

These leads should in no way attach to the boat wiring harness, except possibly for the black lead (if you have a fuel gauge). Just to be consistent I normally keep the black lead separate from the wiring harness also. The pink lead from the fuel gauge will need to go through the boat wiring harness to get to the fuel sender.

I hope I did not just make things more confusing...after all, you did just ask me "what time it was" and I told you "how to build the clock".

The wiring diagram of the motor and wiring harness should help you trace things down, if you are comfortable reading wiring diagrams. There is one at the end of the owner's manual. If you do not have one, you can download one for free from Honda. http://marine.honda.com/owners/manuals/models/BF50 Just find the right one by using the serial number on the mounting bracket of the engine.

Mike
 
Hi Mike,

You described exactly the wire colors I have on my boat. I don't have a trim gauge but I do have a fuel gauge. The blue wire does jumper to all the gauges and connects to the Nav light switch. I will have to cut the wire ties too seem if there is a Honda wire harness but I will try the system out without the Tach first, to see if it might be the Voltage, Fuel or Speedometer that might be causing the problem. If it still blows the fuse, I will remove the positive IGN wire (purple) from each gauge until I find the gauges that is causing the problem.

When I was measuring voltages on the wires trying to ID which was what, I notice that with nothing turned on, I measured +11 volts on the gray wire (signal wire) is that normal?

Thanks,

Neil
 
About the grey wire, I am not sure what voltage is there. It might be ok, it comes right from the regulator/rect. I am not at work for a few days, so can not just check one. The Faria troubleshooting says there should be about 2v there when the power is applied to the gauge, so I am still not sure what it on the lead when it is not connected and the gauge is not turned on.

Before you go disconnecting the purple lead from all of the gauges....I can tell you that the original wiring is on the gauges...so

follow the purple lead from the gauges and see where it is connected. It should eventually connect to the black/yellow lead on the Honda harness . At that point, you should also see where the black lead (ground) and the gray lead (tach) from the gauges attaches. That probably will shine some light on things.

Mike
 
Hi Mike,

The purple lead did connect to the black/yellow lead so I connect everthing except for the Tach and ran the motor. I got it up to about 2000 rpm and trim the motor up and down several times, the fuse did not blow. I installed the new Honda Tach and run it up to 5000 rpm and played with the trim, fuse did not blow. The real test is tomorrow, when I will take the boat to a local that will allow me to get it up to full speed and play with the trim before I can say that we fix the problem.


Thanks for the help,


Neil
 
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