Blocking diode is for what..?????

[skeffer]

What is the purpose of the blocking diode on the remote control shifter. Mine is blue and cracked it is bad as I can measure resistance both ways and I know you should only read one way But which way should that be. Also would this prevent the motor from firing

 

[alcan]

Re: Blocking diode is for what..?????

Hi Skeffer<br />The purpose of the diode is to prevent the electrical path of the vacuume switch circut from reaching the "I" terminal of the ignition switch, which would by-pass the key switch. If the diode fails in a closed condition while the engine is running, the vacuume switch would then supply current to the ignition even with the key switch off. If the diode fails in the open condition, it would go unnoticed when starting, because the vacuume switch closes readily, energizing the shift circut.<br /> To check diode separate diode connector to cable assembly. Connect one ohm-meter (hi ohms scale) lead to ignition terminal on key switch and other test lead to diode connector. A normal diode will show a reading in one direction and no reading in the other direction. A test light shiuld show with connections in one direction only.

 

[skeffer]

Re: Blocking diode is for what..?????

well the diode is bad as I get a reading both ways what is the specs for this diode, or do I get on that meets the pwr requirment or is this a special type. I am familiar with electronic parts I just ain't with boat motors this is on a 71 60hp evinrude

 

[alcan]

Re: Blocking diode is for what..?????

Sorry I am not an electronics whiz. But the OMC part # for diode&lead assembly is 383840. There is a gentelman on the board named schmatic he may know the answer to your question. Do a search on some of his posts, see what you can come up with.

 

[petryshyn]

Re: Blocking diode is for what..?????

I will presume you have an electric shift leg. The purpose of the blocking diode is to allow power to the solenoids while cranking, yet prevent the shift diodes from attempting to charge the batteries and run the accessories. This would kill the shift diodes, as they are small in size, and used only to keep in leg in neutral when shutting down.(preventing a lurch)<br /><br />I would sub the diode with a 7amp 400piv replacement....

 

[skeffer]

Re: Blocking diode is for what..?????

well getting that replaced should be easy. I still have the starting issue going to check the coil. I saw in a post how to check the power pack with a light will this work with a amplifier box and are they the same thing.

 

[alcan]

Re: Blocking diode is for what..?????

Hi Skeffer<br />In this case, yes they are talking about the system you have.

 

[skeffer]

Re: Blocking diode is for what..?????

well the coil checks good <br />blue wire to ground-- infinity <br />black wire to ground---infinity <br />blue wire to black wire--0.4 ohms does this sound right as I would think it should be around <br />5 ohms

 

[skeffer]

Re: Blocking diode is for what..?????

schematic :<br />I have a push button shifter made by Evinrude with the diode on a purple/yellow strip wire and the otherend goes to the shifter

 

[alcan]

Re: Blocking diode is for what..?????

Hi Skeffer<br />Post you e-mail add. and I'll send you some info. As I am no whiz, it dosen't take much for me to get lost with this stuff. Don't worry I do just fine as long as I have my books. (in the shop)

 

[skeffer]

Re: Blocking diode is for what..?????

Alcan any info is good my e mail is<br />skeffer@midsouth.rr.com thanks

 

[skeffer]

Re: Blocking diode is for what..?????

I have tested everything i belive that is connected to the wiring on my boat. I belive the amplifier box is bad as I have 12v on the input and 10v constant on the out put when the point wire is grounded the voltage drops to 9.4 and I belive it should be around a 100 or so. I would appreciate any info as to if this is correct or not <br />Alcan thanks for the info it realy helped alot.<br /><br />Also where are some places that I can check on prices for a amp box. The only place I found it was 233.00. My boat may not make it in the water the summer