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2002 50a indicator lights what voltage.

C

Chubbsdad

Member
Hi all
You may well have seen my other thread " BF50 choke to Se carbs" its all related . I am trying to refurbish a 2002 50A the unit runs in a water barrel and I have it wired into an automobile start switch . The switch unit consists of 2 x on off toggle switches a push start button and 2 x 12 volt lights one Red the other Green . The start switch is temporary for test purposes and I would like to wire in my oil pressure switch to the green indicator light.
Taking a measurement from the oil pressure switch to ground at idle rpm I get around 27 volts dc.
Can any body confirm this is the correct voltage . I know the honda remote indicators are LED units but according to the Selco manual you can test them with a 12 volt battery. Therfore I assumed that the circuit would produce around 12 volts when running ?
The pressure switch must be functional as it shows continuity when stopped and open circuit when running. 27 volts would be a tad too high for a 12 volt lamp so either my switch is faulty or my oil pressure is low ?
thanks
 
Not sure how you are measuring, but the lights get 12v from the key switch. The BF50A normally has a light module that is powered by 12v and if the ground from the oil pressure sensor opens (with good oil pressure), the green light goes on. In other words, when you remove the ground to the Yellow lead going to the module, the module oil light lights.

Since you do not have that module and you are just using lamps, your oil light will work just the opposite and the manual indicates. The light will be out until the oil pressure goes down below the threshold of the oil pressure switch. At that time, the switch will send a ground to the lamp and light it.

You could be creative, if you wanted to wanted to make it work the standard way. If you feed the switched 12v to the lamp through two resistors in series and connected the other side of the lamp to a permanent ground....then connect the yellow lead from the oil pressure switch to the point where the two resistors connect, then it would work as Honda describes. If you used leds, then you could use pretty large value resistors and that would minimize any excessive current draw and heat dissipation.

Back to your measurements.....

The pressure switch is just a switch. It is on or off. It does not generate any voltage.

Mike
 
Hi Mike
Well Electrics was never my strong point ,however your explanation is great and I now understand the circuit.
I measured the voltage on the Yellow to Ground, not sure how I get the 27 volts but thats what I get .
I will have to check the wiring to see is all is ok . I also measured the voltage on the Red ( thermo valve ) and got a similar result. Regarding the switch I thought it was like a pressure sender altering the resistance in relation to the pressure ,but its just a plain on / off !!
Thanks Andy
 
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Seeing 27 Volts might indicate that it's connected from a 'raw' source out of the flywheel coil, prior to passing through your CDI or Diode Module, that voltage should vary w/RPM. Also that would be A/C voltage and you would need to select that scale on your OHM Meter.

My ancient ('86) BF-100E has an indicator light on the front of case which lights when oil pressure completes its ground. Power was supplied by a yellow wire at 7 volts or so (as I recall) from the CDI module. If the bulb blew, you had to replace the whole socket and wire unit at $30+ US. I just located a very tiny, 12 Volt LED (from an automobile dashboard) and squeezed it into existing socket and tapped power from DC Plug (+) feed (disconnected feed from CDI). I had 12 volts above idle speed and if 12V Battery was plugged in, continuously and lighting LED when Oil Pressure switch closed.

Follow the link above to see that socket/wire and the huge list below of engines using it, which I would expect might include your engine as well.
Art
 
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Excellent link from Mike for you !!! With any used engine, you must look out for previous user's modifications to the wiring. I mentioned just one mod I had done and anything like that gets recorded in SM for future reference.

Looks like I may need to re-power from my Main Yamaha 90TLR and the additional 57 to 140 pounds of current engines will crowd my 77lb Honda off my transom. I will pass SM along with it, but local Honda Dealer wants it to hang on his wall to display Honda's longevity. :) I love that little engine and it's five years older than my failing Yammy and still going strong.
Art
 
Thanks for the link Mike. I did download it before,but I found the lettering difficult to recognise . I have the Selco manual and it has a similar diagram which is a bit better. On that point I should say that the Selco manual in poor quality in my mind and not worth the money I paid for it.
 
My downloaded BF75-100 Owners Manual (45 Letter-Size Pages) Printed out a clear diagram, sorry about yours or could you try another download?

The Honda Factory Service Manual is excellent, I feel no need to supplement it with Seloc's or Clymer's.

My Yamaha Factory Manual is less 'user orientated' and for that you need the after-market Manual/s as well.

Check your local Library for a copy of your Honda Factory Service Manual. In the US, Library's have a program where they can connect with other Libraries and obtain books that are not in stock. If you must buy one, eBay (with care) would be a good source.

I highly recommend the Honda Factory Service Manual. It's well written and Illustrated and goes far deeper into the 'Why & How" than the Yamaha SM.
Art
 
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Thanks for your comments Art , over the last few years I have collected ,downloaded a number of manuals, however most of them are american publications and I am never too sure if they are different to the european models. I even joined Seloc on line !! That was my worst investment ,what a waste of time and money ��.
The most recent was the 50A user guide from Honda Com europe unfortunately it has 2007 date stamp and therfore the wiring diagrams are different. Recently I discovered this great forum think is called " Marinengine.com" or something -----they have real time guys who offer great advice and have terriffic experience . The best investment I have made ��������
Sometimes for me ,I need a bit of a break ,away from "Things that go up and down and round and round "
so I have just come back from ------Star Wars---- awesome ✔️ long live the Force
cheers
Andy
 
Pardon if you've already been to this site, but I just discovered it:
http://boatinfo.no/lib/honda/manuals/bf40bf50.html#/202

They claim to maintain the largest library on the net, can't download, but you Can Print.

Link above opens to a genuine Honda Service Manual and page 202 of 435 looks like it was getting into some electrical parts.
This is their main Marine Engine "Library" page:
http://boatinfo.no/lib/library.html

On their Yamaha page, they have Seloc instead of Factory, so they agree with my observation that Honda Factory SM is best, while Seloc is better for Yamaha.

Could be a SA site as some of their 'anchor' pages were Google translated from Afrikaans. Definitely a work in progress as I encountered a lot of '404' errors, but not on any Marine Publications.

Happy you got to see Star Wars:D
Art
 
My post with a link to the Honda Factory Service Manuals that you can read and print seems to cause my posts to disappear immediately. But searching this site for that, shows them all over here, here's one:
http://www.marineengine.com/boat-fo...s-available-online&highlight=boatinfo+library

They seem to have it all, even agreeing with my observation that Seloc is great for Yamaha, but Honda Factory Service Manuals are best for Honda's.:cool:
You may need to zoom out to see the whole library.

Happy you got to enjoy the new Star Wars and have a Great Holiday!
Art
 
Hi all just a quick update.
I did the simple thing and wired the indicator to work the opposite way . So now its just like a car Red indicator On ignition On , no Lub oil pressure. Red indicator Off engine running Lub oil pressure .
Andy
 
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