'79 40 hp Merc 400 STOPPED sparking...

[steveo_the_newbie]

I have a '79 or '80 Mercury 400 outboart that's 40 horse. I checked the lines, checked the spark...all was good. I got the engine running for about three minuts. Then it stalled. No spark now. Plenty of gas where its supposed to be. There is some sort of sliding cable on top of the fly wheel that seems to be disconnected, so it doesn't move some other parts when the cable moves. So any Idea's? Are the cable and the no spark inter-related? Or did I do something BAD like blow the ignition module (I think thats what its called... the big expensive looking thing that all the wires go to)?? Any help would be nice.

 

[Plainsman]

Re: '79 40 hp Merc 400 STOPPED sparking...

Could be the switch box. That was what happened to mine. New one was 400 but found a used one for 80.

Can you give the serail # of the motor as well as a photo of the cable that is disconnected? You can upload it to photobucket.com for free.

There are many here who will help you diagnose this.

Wekcome to iboats Steve!

 

[steveo_the_newbie]

Re: '79 40 hp Merc 400 STOPPED sparking...

Ok. The serial number is 3043424. I did some reserch and apparently its a '71 model. I have two pictures of the cable on top.

http://s52.photobucket.com/albums/g...urrent=PICT0002.jpg&refPage=&imgAnch=imgAnch3

http://s52.photobucket.com/albums/g...urrent=PICT0003.jpg&refPage=&imgAnch=imgAnch2

http://s52.photobucket.com/albums/g...urrent=89433e82.jpg&refPage=&imgAnch=imgAnch4

It looks like there is a ground wire between the lower and upper unit that is cut. Its the same on both sides. You'll see in the picture.
http://s52.photobucket.com/albums/g...rrent=PICT00061.jpg&refPage=&imgAnch=imgAnch1

If all that doesn't work... its posted on photobucket. My username is the same. steveo_the_newbie

 

[tashasdaddy]

Re: '79 40 hp Merc 400 STOPPED sparking...

steveo resize you pictures, very blurry.

 

[Plainsman]

Re: '79 40 hp Merc 400 STOPPED sparking...

Use the macro feature on the camera for such a close picture.

 

[steveo_the_newbie]

Re: '79 40 hp Merc 400 STOPPED sparking...

Ok, sorry bout that everyone. Here is the in-focus ones.

Broken? thing on flywheel.

http://s52.photobucket.com/albums/g...urrent=PICT0009.jpg&refPage=&imgAnch=imgAnch1

http://s52.photobucket.com/albums/g...urrent=PICT0008.jpg&refPage=&imgAnch=imgAnch2

http://s52.photobucket.com/albums/g...urrent=PICT0007.jpg&refPage=&imgAnch=imgAnch4

If you look at the second picture, you can see what is supposed to slide. It moves along the groove you see

Cut ground between upper and lower unit.

http://s52.photobucket.com/albums/g23/steveo_the_newbie/?action=view&current=PICT0010.jpg&refPage=&imgAnch=imgAnch3[/url]

If anyone needs more pictures, ones taken from farther away, etc, let me know.

 

[Plainsman]

Re: '79 40 hp Merc 400 STOPPED sparking...

Now that the closeups are clear, could you take one further away to get perspective?

 

[steveo_the_newbie]

Re: '79 40 hp Merc 400 STOPPED sparking...

Here are the shots from further out.

Cable on top of flywheel
http://s52.photobucket.com/albums/g...rrent=PICT0016.jpg&refPage=&imgAnch=imgAnch2

http://s52.photobucket.com/albums/g...rrent=PICT0013.jpg&refPage=&imgAnch=imgAnch3

Cut wire from upper to lower unit
http://s52.photobucket.com/albums/g...ent=PICT0015-1.jpg&refPage=&imgAnch=imgAnch1

Hope it helps. Oh, and happy 4th everyone

 

[Plainsman]

Re: '79 40 hp Merc 400 STOPPED sparking...

Thanks for the pics. I am not familiar with the motor, but someone here will help I am sure.

The first pic looks as if the cable is connected but came loose from it holding. What does that cable go to if you follow it?

As for the ground, what is on the inside of the motor that it might go to?

 

[steveo_the_newbie]

Re: '79 40 hp Merc 400 STOPPED sparking...

I'm not sure what the ground wire would go to.

I had a friend come over and take a look at the engine... he says the cable on top is for when you pull string start it.

I checked the second spark plug and am getting nothing now. I found a site that gave a list of things to check when you are having mercury starting problems... I'm going to mess with the thing tomorrow and see what I can find out.

 

[Plainsman]

Re: '79 40 hp Merc 400 STOPPED sparking...

Thanks to Calms for this:

»You need to troubleshoot the ignition. Start with the standard switchbox test. If it passes that it's the trigger.

-W
MERCURY BATTERY-POWERED CDI SWITCHBOX TEST
FOR DISTRIBUTOR MODELS


This test is for the 332-2986 switchbox used from 1967-1978 on all the
inlines.

This test assumes your coil is good (most all are).

DISCONNECT BATTERY

1. Turn off ignion
2. Disconnect all 3 wires on the distributor side of the switchbox.
3. Remove the HV lead from the coil to the center cap (remember it unscrews
from cap)
4. Reconnect that HV center lead to the COIL side only.
5. Position that HV lead about about 3/8" from ground (block, shrouds etc)
and find a way to hold it there.
6. Jumper the brown and white terminals on the dist. side of the switchbox
together.

RECONNECT BATTERRY

7. Check that you have +12 V at red terminal.
8. Turn on ignition and verify +12V at white terminal (on red terminal side)
9. Touch the black terminal to ground - unit should cause spark each time
you touch ground.

If this passes and it still won't fire at all, suspect the trigger (distributor).

I wish the more experienced guys would jump in on this.

 

[Plainsman]

Re: '79 40 hp Merc 400 STOPPED sparking...

Look through this Steve:
http://www.iboats.com/bbboard/bbBoard.cgi?a=viewthread;fid=29;gtid=933928

 

[steveo_the_newbie]

Re: '79 40 hp Merc 400 STOPPED sparking...

Thank you for the link.

I removed the flywheel earlier today and took a look at the stator. It has some thin cracks on it in the thinner areas between where it is thicker. I read that cracks warrant replacing the stator.

However, I still don't get why I had it running earlier. I need to run the test you did. I have the same problem with gas leaking out of the carb.

I don't want to fry anything though... So I'm holding off untill I buy a manual for this thing.

 

[steveo_the_newbie]

Re: '79 40 hp Merc 400 STOPPED sparking...

Ps: I partially removed the flywheel. I removed the top part via the 8 bolts, wich allowed me to slip the bigger part of it off. However, there is still a part of it left, and I cannot get a look in the distributor cap. any sugesstions? I do part of the removal wrong?

I can't seem to find anything matching my switch box... so I'm kind of shy about hooking stuff directly to the battery..... do I have nothing to worry about?

 

[Plainsman]

Re: '79 40 hp Merc 400 STOPPED sparking...

You need to get a manual before you take things apart. If your not comfortable about the test, don't' do it.