Help With Auto Choke

[jarway]

Have a 82 150 HP Johnson (Model J150TLC Serial # J5699966) and am having trouble getting the electric choke working. I have done the following diagnostics:<br /><br />Traced wires from choke switch which is transferring 12V OK. Have a purple wire and brown wire that feeds into harness. Brown wire carries the power when the momentary toggle switch is turned on. Wires go to an 8 pin connector at the motor. Female side has eight wires running from dash-- R, W, Y/Bl, Grey, P, P/W and the brown wire which is hot at the plug. The male end on motor side has (2) Bl, (2) W, Grey, R, P, Bl/Y, Y/R and a P/W wire that runs to a "Fuel Primer Valve" There is a label on the motor that explains that one can flip a lever to 2 positions (manual start and run). I can start the motor when I flip the lever to manual start and then turn it back to run. The first time I did this ther was a surge of gas through the line from teh primer valve to teh carbs. I am only getting 1 volt to the valve and also only 1 volt to the connector despite the brown wire carrying 12 V. I checked continuity at the connector and the brown wire goes to a different female post than the purple/white wire on the male side. Futhermore, I get continuity on 3 posts from the P/W wire but none are the same as the Brown feed wire. I jumped the valve directly with a 12 V battery and it clicks which I assume means that it is opening to let fuel flow to the carbs. Since this isn't your typical solenoid/butterfly choke setup, I am not sure what to do next. Instinct says to just run a jumper wire past the connector to the P/W wire that feeds the valve but I am afraid that putting 12 V to it might affect something else due to the fact that the P/W wire comes off of 3 separate terminals at the conector.<br /><br />If anyone has any advice about this problem, I sure would appreciate the help. Taking the cowling off and on just to start the motor is getting to be a pain. Another thought was to just run an individual wire from the choke toggle to the valve which should turn it off and on bypassing the connector altogether??<br /><br />Thanks for listening.

 

[Joe Reeves]

Re: Help With Auto Choke

Brown wire? If you're using a toggle switch, there should be a purple wire leading from the "A" terminal of the ignition switch to the choke/toggle switch.... and a purple/white wire leading from the choke/toggle switch to the primer solenoid.<br /><br />Normally a ignition switch is used that does not require a seperate choke/toggle switch. Said switch would have a terminal marked "C" whereas the purple/white wire would connect to it.

 

[jarway]

Re: Help With Auto Choke

Thanks for the quick reply Joe,<br />I thought that P/W should carry through but for whatever reason there is a brown wire in the harness that goes to the red connector plug and a P/W comes out the other side to the primer solenoid. Despite the color coding do you see any problem just jumping the connector and either tapping into the existing P/W wire or running a new wire right to the solenoid?

 

[jarway]

Re: Help With Auto Choke

First let me say I owe an apology to Joe. I should have learned never to second guess a retired mechanic-- my uncle was an auto inspection mechanic and when I was younger and I always seemed to do it the hard way despite his advice. Well this morning before going to the lake to field test a prop issue (see Prop Analysis post), I decided to pull out the ignition switch again and low and behold the infamous P/W wire was over on the lead to the hot light. Took it off that terminal and put it on the choke switch terminal and the sweet click of the primer solenoid was heard. Not quite sure what the brown wire does but it feeds into the harness and goes back to the connector at the motor. Well maybe someday I'll get the time and ambition to trace it down , but for now, it is taped and disabled under the Center Console. Motor still runs fine so it must not be that important. Will have to figure out a terminal on the ignition switch to jump a wire for the hot light.<br /><br />Any advice about colors Joe??<br /><br />Thanks again for all of the advice from this board. Forums like this allow amateurs like me to have the self confidence to tear into projects like this. I guess this technology stuff isn't all that bad! ;-)))

 

[Joe Reeves]

Re: Help With Auto Choke

Perhaps that wire you speak of is not "Brown" but is rather "Tan". If so, that would lead to the warning sensors in the engine compartment which on your 1982 V6 engine would be 2 Overheating Sensor (one in each head), and 1 fuel restriction sensor.<br /><br />The wiring would be a purple wire leading from the "A" terminal of the ignition switch to one of the warning horn terminals, and that "Tan" wire would attach to the other horn terminal.<br /><br />If using a 3 wire horn that has a internal black wire leading from it, the "Tan" wire would connect to the terminal closest to that black wire. Connecting it to the other terminal will result in false warnings.<br /><br />Note.... Don't even think of using a light instead of the horn. Should the engine overheat, by the time you think of looking at that light, it would be because the engine is coming to a halt and smelling weird!<br /><br />You can test the horn by (engine not running) having the key in the ON position, then grounding out one of the "Tan" wires that you see protruding out of the top are of either cylinder head (heat sensors).

 

[jarway]

Re: Help With Auto Choke

Thanks again Joe. Will trace and check the wiring sequence. The wire is dark brown though and the explanation you gave makes sense. Where would this warning horn be? The only thing I have right now is that hot light on my ignition switch plate which I assumed, until now, that it was just an indicator for when the switch was on. Come to think of it, the other wire on the light is a purple wire but I have to check which post from the ignition switch it comes from. I could probably find some kind of buzzer or horn somewhere to wire in. Any ideas about sources?<br /><br />Thanks again. It looks like I'll have her ready to take down to Chincoteague next weekend for fun in saltwater.

 

[Joe Reeves]

Re: Help With Auto Choke

Ignition switch plate with a light on it? Sounds like you're using a instrument wiring harness setup from the 1960s or early 1970s.<br /><br />The heat warning light was done away with in 1971 in preference of the warning horn setup.<br /><br />The older wiring harnesses did have a dark brown wire which pertained to the generator type charging system, and that connected to a voltage regulator.<br /><br />If that wiring harness is indeed the older type harness, I'd suggest that you obtain the proper instrument wiring harness (engine to dash). As it stands, connecting one wire wrong could be a very expensive error.<br /><br />Does the instrument cable harness have a red plug that plugs into another red electrical plug at the engine? If so, is some other older harness spliced into it? Something is not right with that wiring if your engine is indeed a 1982 V6 Johnson or Evinrude.

 

[jarway]

Re: Help With Auto Choke

Joe,<br />I listed the model and serial number of the motor in first post. I checked the numbers with the OMC coding and believe that it is an 82. The instrument cable harness does have a red plug that connects with a red plug at the motor. No splices between connector plug and ignition-- straight shot with wires.<br /><br />I bought the motor used last fall and it looked to be in good condition and well maintained. I was happy to see it turn over quickly last week after I finished setting it up on the boat I restored and yesterday it pushed the Sea Nymph about 35 MPH. Still playing with props and WOT and motor height on transom. There is a slight miss/hesitation that I hope to fix by checking timing when I get the shop manual CD that I just ordered. I decarbed and put in new plugs and not much carbon out the exhaust on the decarb and visual inspection shows carbs look clean.<br /><br />Now you've got me wondering about what to do with that brown wire. It wouldn't surprise me that is an older harness since it came off of a deck boat that was older. Do you think I should connect it to the terminal on the hot light and also wire in a buzzer or some audible signal to that circuit or just forget it and let it taped under the dash? In the meantime, I'll look around to see if I can find a harness of the same vintage as the motor. Thanks again for your expert advice. No way I would have any chance of figuring this out myself.

 

[Joe Reeves]

Re: Help With Auto Choke

A instrument wiring harness with a RED electrical plug and no splices would be the correct wiring harness for a 1982 OMC V6. The harnesses were identical thruout the years and horsepowers as long as they had the RED plug. No need to look for another. However, that dark brown wire you speak of does sound strange as it doesn't exist in any wiring diagram or in my memory.<br /><br />When you get a chance, check it out with a ohm meter to see if it is actually connected to the two TAN heat sensors at the top areas of the cylinder heads. Disconnect both TAN wires to avoid a false reading due to feedback.<br /><br />The vacuum switch I may have mentioned at one time or another should not exist as that item was not incorporated on the V6 engines until 1984.

 

[jarway]

Re: Help With Auto Choke

Thanks again Joe. Will check out and report back sometime later this week.