mercury outboard 40 HP Model 402

[kai in the sun]

Hi all watersportsfans! I have a mercury 40 HP model 402 ( blue ) ! But if I start the engine it runs for an half houre! Than it stop! :-( I can´t find the problem, becauce I haven´t the service manuels of this engine! I have two meanings, the switch box or the stator have a problem! Can I measure the voltage or other tricks???<br />Please help a german student with a low budget!

 

[Mod2]

Re: mercury outboard 40 HP Model 402

Welcome to iboats kai....I'm going to move your post to the Mercury/Mariner forum. You'll get a quicker response there.

 

[dilligafda]

Re: mercury outboard 40 HP Model 402

Welcome kai! You don't mention in your post how the engine dies. Does it slow down and stop running or quit like you turned off the key? If it slows down to a stop, you may have a fuel delivery issue. Try squirting fome fuel into the carb or squeezing the primer bulb when it does that and see if it picks up and runs. WWill the engine restart right away? If it does, I would not be suspect of the ignition.<br /><br />Try the fuel thing and try to give a better idea of how it quits and we can offer a bit more help.<br /><br />Good Luck!

 

[kai in the sun]

Re: mercury outboard 40 HP Model 402

At first I say thank you!<br />It´s not a fuel problem, I know! The engine stop quickly and won´t restart! I must wait an half houre, than it runs! I think it is a teperature problem! The ignition don´t work at the standby time! I saw it at the sparks! The cooling system is working! Did the switch box have a teperature secruity? Produce the engine not to mutch voltage and need to mutch ampere?? I need some values to measuare or to control the stator!<br /><br />wish a nice day<br /><br />Kai in the sun

 

[dilligafda]

Re: mercury outboard 40 HP Model 402

OK that's the more information I needed. There is no test for the switch box itself, you have to eliminate all the components around it. The first place to check is the stator. With a peak reading volt meter, you should have a minimum of 200v on the blue stator lead and a minimum of 10v on the red stator lead. Then check the trigger leads. You should have at least 0.5v on each of the brown and white leads. Then you can check output on the switchbox green terminals. There should be stator voltage there.<br /><br /> Of course you will have to check all of this after the engine quits, but you should be able to find the problem. If the voltages are correct, then replace the switchbox. <br /><br />You may ask how I know all of this. It's because I own the same engine that had the same problem this last year. Mine turned out to be the stator, yours may be different.<br /><br />Keep us informed.

 

[kai in the sun]

Re: mercury outboard 40 HP Model 402

Thank you for your inportant information!<br />At "märz" I will start to repair the engine! If you want, I send you some pictures of my boat! I gave you my email: k.flecke@freenet.de ! Than we can stay in contact!<br />Thanks for all!<br />I think, it is the stator!!! Do you konw how expenciv it is? And what coast a switch box?<br /><br />greatings from<br /><br />Kai in the sun

 

[Francis Frogg]

Re: mercury outboard 40 HP Model 402

DILLIGAF, Do you have a Mercury or Sierra part number for this stator? I need one badly.Francis Frogg.

 

[dilligafda]

Re: mercury outboard 40 HP Model 402

The Merc number is 398-5255 and runs about $185.00 The Sierra part # is 18-5856 and retails around $182.00. You might want to check locally, even though I don't recommend it, for a used one. If you do, make sure it has some kind of warranty with it!<br /><br />Good luck!

 

[Francis Frogg]

Re: mercury outboard 40 HP Model 402

Dilligaf, Thank you very much for the part number. Francis

 

[kai in the sun]

Re: mercury outboard 40 HP Model 402

Hello! I have now a new problem. The engine ran only briefly, but I can´t start again.I removed the switchbox and would like to<br />know, whether someone to me can say, how can I check it ? It is also not cheap.<br /><br />Thank´s<br /><br />Kai in the sun

 

[kai in the sun]

Re: mercury outboard 40 HP Model 402

I forget the Motornumber: 3404996<br />And the number of the switchbox is: 338-4733(A2)

 

[dilligafda]

Re: mercury outboard 40 HP Model 402

Unfortunately, there is no checks for the switchbox. THe only way to diagnose a failed switchbox is to eliminate all the components around it. Start with the stator, then the trigger and finally the coils. If all of that checks out, then the switchbox is bad.<br /><br />Good luck!

 

[kai in the sun]

Re: mercury outboard 40 HP Model 402

Can you gave me an adress where can I buy/order a new switchbox?<br />And thank´s for your help!!!<br /><br />Kai in the sun

 

[kai in the sun]

Re: mercury outboard 40 HP Model 402

Hi all!<br />I think, I have found the problem.<br />The machine runs and stopped after some time.<br />Saw, which the cooling waterjet precipitates after some time.<br />I need repair manuals! Can I open the<br />transmission? Ist there a prob of the impeller?!<br /><br />greet<br /><br />Kai ...