Merc 402 1975 40HP Electric Choke Problems

[PeteMax402]

I have just completely rebuilt a merc 402 from scratch. I have it running, but I am having diffuculty getting the electric choke working properly. It was working when I took it off of the motor, but now nothing. This choke has a plunger that moves up and down closing the choke on the carb. Any help will be greatly appreciated. <br /><br />Also any feedback on how to time the engine with out using a test tank or running at WOT In forward gear as suggested by the manual would be a great help. Could I time it with the fresh water flushing device hooked up? Will that hurt the engine?

 

[oresaway]

Re: Merc 402 1975 40HP Electric Choke Problems

Sometimes the contact located at the plug that connects the remote control to the motor itself can be dirty or not seated properly. Try disconnecting the plug and reconnecting to assure it is seated correctly.

 

[dilligafda]

Re: Merc 402 1975 40HP Electric Choke Problems

Pete,<br /><br />You can test the solenoid by applying 12v to it direct from the battery. Make sure that the plunger is in place and touch a jumper lead from the battery side of the starter solenoid. If the choke works at that point, you need to look into the wiring harness or switch.<br /><br />As far as the timing at WOT goes, that can be done while cranking the engine with a remote start button, the plugs removed and a spark tester in place and prop removed with the throttle fully advanced to the wide open position. Put an inductive timing light on the #1 spark plug lead and set the timing while cranking the engine. The WOT timing for this engine is 27 degrees BTDC. While cranking, set the timing at 25 degrees. This will bring the timing into the correct range while running.<br /><br />DO NOT RUN THE MOTOR AT WIDE OPEN ON A FLUSH ATTACHMENT!!!!!!!!!!<br /><br />Hope this helps!

 

[PeteMax402]

Re: Merc 402 1975 40HP Electric Choke Problems

Thanks for the quick answers. I am going to try this weekend.

 

[PeteMax402]

Re: Merc 402 1975 40HP Electric Choke Problems

Dilligaf, <br /><br />I was thinking about your reply when I realized that I have no Idea on how to set the timeing to a degree. I have the procedure for timing the engine in the manual, but it does not mention how to set the degrees. <br /><br />So how do you do that? <br /><br />Do I need special tools? <br /><br />Also the manual says something about timing it at 2 different RPM Ranges. <br /><br />Does that mean that I cannot do what you suggested in your last post?<br /><br />Again any help you can provide will be greatly appreciated.

 

[dilligafda]

Re: Merc 402 1975 40HP Electric Choke Problems

The only special tools you need are a timing light and remote start button. Follow the procedures I outlined and your timing will be good. The 2 speeds that are mentioned in the manual are idle and wide open. You can set both, the idle while running in a test tank or on the water and the wide open throttle while cranking. There are seperate adjustments for both.<br /><br />Happy boating!

 

[PeteMax402]

Re: Merc 402 1975 40HP Electric Choke Problems

Dilligaf, <br /> Thanks for all your help. I timed it as you suggested and now it is purring. I also fixed the choke problem. It turns out that the plunger fell out during assembly.