no fire 1983 150 hp v6 johnson ob

[oldsubsailor]

I just purchased this boat and motor and know absolutely nothing about them. I cannot get the motor to start. It ran at an idle hooked to a hose when I was looking at it prior to purchase. Have not been able to get it to start since I brought it home. It was giving me a half start, then the starter would disengage and spin down. Now I don't even get that so I checked the fire with a spark tester, no spark on either the port or starboard bank. Went to the book and it said to check resistance between the leads at the four pin connector that " connects the leads from the power pack to the timer base". This I did, I get good readings on the port bank (12 ohm) and the same readings on the starboard bank on all except 1 pin, D to A reads 34 ohms, the other 3 read as should. The book now tells me that I need to replace the sensor coil. I am not sure this is the problem, mainly because when I pulled the plugs out and did a compression check on all 6 cylinders, I noticed that #2 plug looked as if it had never been fired, looks brand new the other 5 plugs looked used, not bad, just you could tell that they were firing. I talked to the previous owner whom had the boat for about 2 or 3 years and took it out and operated it about 3 years ago then decided to redo the deck and furniture and such. He states that he did not replace the plugs at anytime when he had the boat. I know the boat was running (idle) and that the # 2 cylinder was not firing for some reason or another and that now, I have nothing for fire on anything. Does this sound like a sensor coil and is the sensor coil something that I could replace myself or is it a highly technical procedure requiring special tools and gauges and the like.

 

[James R]

First check that the dead man switch on the control box is activated, This is usually activated by by a snap in device attached to a pull line. If you are not sure of this disconnect the big red plug inside the motor and operate the starter solenoid with a jumper wire between the positive battery connection on the solenoid and the yellow striped wire connection on the solenoid. this will turn the motor over so that you can observe the spark, This isolates any problem with the ignition switch and dead man switch. If this doesn't work we will need to go deeper.

 

[oldsubsailor]

very good. I did disconnect the red plug, I have fire on 5 of the 6 plugs. Now I will go to work finding out why the dead man switch is not operating correctly and why I have no fire on the #2 plug. Would one plug missing fire be enough to keep this thing from running? I would think that it would start, just run rough. Just wondering. Commander James, I salute you for your info. Why didn't my book say that? Maybe I just missed it.

 

[emdsapmgr]

Your engine has two identical power packs. Each controls the spark on one head. You can swap them. In the process, you may find the "no spark" plug may switch from one head to the other. That would indicate a bad pack. If nothing changes, I'd check the cranking output for the timer base. Possible it is not working on all 6 cyls. You will need a special " peak-reading" voltmeter. Check out the ignition troubleshooting tips for your exact engine at this website: cdielectronics.com

 

[oldsubsailor]

Thanks for all of your info. It turned out to be the power pack and just as you said, the missing fire traveled over to the other side when the pack was swapped. replaced the pack. We also found a bad ignition switch (intermittent contact) which has been replaced. We continue on down the path to getting this baby back in the water. Thank you for all your help.