Chrysler 75hp outboard wiring questions, Please help

[davidschaffer]

Hello. I am new to the forum and new to this motor. I picked up a 75hp Chrysler to put on my boat. I am not sure of the year of the motor but probably mid 70's. It is a 3 plug, 3 carb and appears to be in good shape. I am trying to figure out the ignition wiring. I have the wires connected at the motor but not sure how to connect to the switch. I found a diagram but it was for less wires then I have. The way I have it wired now, when I connect the neg bat. cable, the motor tries to turn over. there are also random disconnected wires in the motor ( not part of the ignition harness ). Are there any diagrams around for this. I appreciate any help you can give.

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help

I should add that the switch is labeled C A M B M S. None of the diagrams that I have found show A. It is a Magnapower ignition. Thanks.

 

[Frank Acampora]

Re: Chrysler 75hp outboard wiring questions, Please help

Dave: Welcome. "C" is choke. "A" is accessories or ignition. It is a switched 12 volt source on only when the switch is in start or run position. Both "M" are magneto--they are not used on distributor engines and are the stop circuit on Prestolite ignitions. "B" is battery and supplies constant power to the switch. "S" is start.

Now, if you have a distributor engine, red connects to the "B" terminal and blue connects to the "A" terminal. Green is choke and yellow is start. No other wires are connected to the switch. The black is a common ground and can be used on a terminal block under the dash. orange is the overheat indicator. White is a tachometer signal wire and purple is just completely unused.

If your engine does NOT have a distributor, then purple is tachometer signal, blue connects to one "M" terminal and white connects to the other "M". Red, yellow, and green are the same as above.

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help

Dave: Welcome. "C" is choke. "A" is accessories or ignition. It is a switched 12 volt source on only when the switch is in start or run position. Both "M" are magneto--they are not used on distributor engines and are the stop circuit on Prestolite ignitions. "B" is battery and supplies constant power to the switch. "S" is start.

Now, if you have a distributor engine, red connects to the "B" terminal and blue connects to the "A" terminal. Green is choke and yellow is start. No other wires are connected to the switch. The black is a common ground and can be used on a terminal block under the dash. orange is the overheat indicator. White is a tachometer signal wire and purple is just completely unused.

If your engine does NOT have a distributor, then purple is tachometer signal, blue connects to one "M" terminal and white connects to the other "M". Red, yellow, and green are the same as above.

Thank you for the info, it is very helpful. I believe I have the ignition wired correctly but am getting no response when I turn the key ( I have no key so am using a screwdriver, the previous owner said this would work ). There are some wires on the motor that are not connected. One small red wire that looks like it should attach to the starter solenoid but when I attach it there the motor cranks a little for no reason. there are two black wires near the flywheel, one is connected ( grounded ) the other is not. I will try and take a picture. Is there a wiring diagram around here or a down loadable manual. Thank you. Also, does the ground wire at the ignition need to be connected for the system to work? and can I ground it to the throttle housing? Thanks

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help



So here are some pic's. You can see a red wire and a yellow wire near the starter solenoid not connected to anything. If I connect the red wire to the solenoid the motor tries to kick over a little. There is also that black wire near the flywheel going nowhere. Any ideas? Also a little black wire you can see at the bottom of the pic.

 

[Frank Acampora]

Re: Chrysler 75hp outboard wiring questions, Please help

Oh! You have an old one there! It has the red selenium rectifier with a trip regulator.

Because of the non-standard wiring, make all changes with the battery disconnected. I do see one wire at the solenoid that appears to have been overheated.

At any rate, at the solenoid, the yellow wire is the start wire and needs to be connected to the small terminal. These early solenoids were grounded through the mount. The large terminal on the red wire should be connected to the battery side of the solenoid. This is the way the engine recharges the battery.

The black wires are grounds and usually they ground the distributor to the block and the rectifier. Your rectifier appears to be incorrectly wired. The yellow wire appears to connect to the start terminal and the yellow in the cable to the switch. disconnect that short yellow, reconnect the yellow in the wire loom that is now hanging free near the terminal, and use the cable yellow as a start circuit as I explained earlier.

It appears that there is a heavier red wire with a yellow termination attached between the battery side of the solenoid and the engine terminal block. This will supply constant power to the CD box without benefit of the circuit breaker protection and should be removed. The P.O. may have had electrical troubles and decided to rewire the engine in an effort to correct them. Getting late now but tomorrow I will post you a couple of photos of a similarly wired engine.

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help

Oh! You have an old one there! It has the red selenium rectifier with a trip regulator.

Because of the non-standard wiring, make all changes with the battery disconnected. I do see one wire at the solenoid that appears to have been overheated.

At any rate, at the solenoid, the yellow wire is the start wire and needs to be connected to the small terminal. These early solenoids were grounded through the mount. The large terminal on the red wire should be connected to the battery side of the solenoid. This is the way the engine recharges the battery.

The black wires are grounds and usually they ground the distributor to the block and the rectifier. Your rectifier appears to be incorrectly wired. The yellow wire appears to connect to the start terminal and the yellow in the cable to the switch. disconnect that short yellow, reconnect the yellow in the wire loom that is now hanging free near the terminal, and use the cable yellow as a start circuit as I explained earlier.

It appears that there is a heavier red wire with a yellow termination attached between the battery side of the solenoid and the engine terminal block. This will supply constant power to the CD box without benefit of the circuit breaker protection and should be removed. The P.O. may have had electrical troubles and decided to rewire the engine in an effort to correct them. Getting late now but tomorrow I will post you a couple of photos of a similarly wired engine.

Thank you for the reply. I will take some better pics tomorrow. The yellow wire on the loom ( from ignition ) is connected to the labeled terminals on the right of the motor. There was another yellow wire that I attached to the transistor? ( not sure what it is ). I think better pics will help. Thanks again.

 

[Frank Acampora]

Re: Chrysler 75hp outboard wiring questions, Please help

My photos turned out really crappy and will probably confuse you more so I didn't post them. None of my engines have the senelium rectifier with trip regulator and none have the solenoid grounded through the mounting bolt.

Do take a couple of photos showing the complete wiring and also the distributor side so I can see if you have a points or electric eye distributor.

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help



I will try for better pics tomorrow. The red wire with the big ring and the yellow wire with the smaller ring come off the same group of wires and go to the other side of the motor. It sounds like I need to connect the yellow wire to the small terminal on top of the solenoid and the small red wire with the big ring to the battery side of the solenoid. Anyways, I really appreciate the help and will try for some better pics in the daylight.

I paid $150 for the motor and was told it ran great when it was used last. I bought a boat last summer and after putting almost $800 in to the lower end of the Mercury 650 that came with my $350 boat, the motor needs more work. This Chrysler came up for a good price and is way easier to work on. I hope she fires once the wiring is worked out.

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help



Hopefully these do the trick. Thanks again.

 

[Nordin]

Re: Chrysler 75hp outboard wiring questions, Please help

Looks like you have an 1978 (decals and paint on hood) but with an oldstyle rectifier and tripregulator. The distributor is electronic with an preamp eye. The yellow wire should be connected to the small terminal at the startersoleinoid.
It comes from the neutral interlockswitch that make sure you do not start the engine in gear (yellow wire in harness and S terminal at switch).
Red wire with large ring should be at the hotside of startersolenoid.
At terminalstrip there are two blue wires one feed the preamp at the distributor with 12V when the ign.switch is in ign.possision (A terminal at switch). The other blue feed CD module with 12V .

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help

Looks like you have an 1978 (decals and paint on hood) but with an oldstyle rectifier and tripregulator. The distributor is electronic with an preamp eye. The yellow wire should be connected to the small terminal at the startersoleinoid.
It comes from the neutral interlockswitch that make sure you do not start the engine in gear (yellow wire in harness and S terminal at switch).
Red wire with large ring should be at the hotside of startersolenoid.
At terminalstrip there are two blue wires one feed the preamp at the distributor with 12V when the ign.switch is in ign.possision (A terminal at switch). The other blue feed CD module with 12V .

Thank you for the reply. I hooked it up that way but no luck. I don't have the key for the ignition but believe that I am able to turn it far enough to start with a screwdriver. It would randomly make a click sound but thats about all.

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help



Here is how I have it connected now. It won't try to turn over but somtimes the choke will click. I have more pics to post.

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help



Is there a way to bypass the key and jump start ( hotwire ) the motor?

 

[Frank Acampora]

Re: Chrysler 75hp outboard wiring questions, Please help

Yes, simply jump from battery side of solenoid to the small yellow terminal. This will close the solenoid and allow voltage to the starter.

NOW: The rectifier is wired incorrectly. The two black wires that come from under the flywheel are AC leads from the stator. Attach them to the outside terminals (yellow tipped) on the rectifier. Attach the small red wire from the center terminal of the rectifier to the trip regulator (done already). Remove the yellow wire that appears to be attached from the yellow on the terminal board to the rectifier. Purple can stay where it is. Wire the switch as I described in previous answers.

Near the solenoid, disconnect the red attached to the yellow with black tracer. Extend the yellow/black to the neutral interlock switch below the carbs. Be certain the yellow from the switch to the small solenoid terminal is connected and functioning. Green also appears to be attached to this red. Run green directly from the engine terminal board to the choke solenoid. The choke is activated by pushing in on the key and holding it in.

Man! This guy really messed with the wiring!

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help

Yes, simply jump from battery side of solenoid to the small yellow terminal. This will close the solenoid and allow voltage to the starter.

NOW: The rectifier is wired incorrectly. The two black wires that come from under the flywheel are AC leads from the stator. Attach them to the outside terminals (yellow tipped) on the rectifier. Attach the small red wire from the center terminal of the rectifier to the trip regulator (done already). Remove the yellow wire that appears to be attached from the yellow on the terminal board to the rectifier. Purple can stay where it is. Wire the switch as I described in previous answers.

Near the solenoid, disconnect the red attached to the yellow with black tracer. Extend the yellow/black to the neutral interlock switch below the carbs. Be certain the yellow from the switch to the small solenoid terminal is connected and functioning. Green also appears to be attached to this red. Run green directly from the engine terminal board to the choke solenoid. The choke is activated by pushing in on the key and holding it in.

Man! This guy really messed with the wiring!

Alright, finally back in town. Thank you for the reply. I have a few questions.
There is only one rectifier tab open ( previously had the yellow wire from terminal ). I attached the hanging black wire but left the other black wire where it was (grounded) for now. What should I do about that. Also, what should I do with the yellow jumper wire that is now hanging from the terminal. When I disconnect the small red wire off of the solenoid where should I reconnect it?

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help



The first pic is the yellow wire connected to the terminal ( where should this go ? )
Second pick is of the rectifier and the black wires.
Third pic is of the red wire on the solenoid ( other end connected to the battery post on terminal ) where should it go if not to the solenoid?
I believe everything else is connected as you have described.

Thank you.

 

[Frank Acampora]

Re: Chrysler 75hp outboard wiring questions, Please help

Remove that short yellow wire. It does not belong. Take the black wire that is grounded to the starter mount and connect it to the same terminal on the selenium rectifier as the purple wire. Purple can stay or you can remove it--whatever pleases you. It is not used on your engine.

Wires on the solenoid are correct.

 

[davidschaffer]

Re: Chrysler 75hp outboard wiring questions, Please help

Remove that short yellow wire. It does not belong. Take the black wire that is grounded to the starter mount and connect it to the same terminal on the selenium rectifier as the purple wire. Purple can stay or you can remove it--whatever pleases you. It is not used on your engine.

Wires on the solenoid are correct.

Finally have some more time to work on the motor. I bought a new ignition switch with key and the motor cranks but slowly. I used a jumper to give the battery a burst of power but it did not last long. Its just not cranking fast enough. I have a charger on the battery and hope that this will do the trick. The cables at the the battery get pretty hot really quick, Is this normal? Also, is there an easy way to get starter fluid into the carbs and witch carb would need it the most on start up? Thanks