Help, No Fire On Two Cylinders...

[Striper Rig]

I have been working on a Mercury 175 v6 1977 ob...
I had to put head gasket on the left side of the motor, because it was blown at # two cly...Fixed problem...
I also put a head gasket on the right side...
I thought I was getting water in the #3 cyl, but I found out a little while ago that the motor is not getting fire on the #3 cyl, on the right side...
So I checked all fire on plugs and found I was not getting fire on the #6 cyl also...on the left side of the motor....

The rest of plugs are firing blue sparks when I checked them....

Plugs and coil wires are ok...

What do I need to check next with no fire on #3 + #6 cyl's...?

 

[Striper Rig]

Re: Help, No Fire On Two Cylinders...

Forgot to mention the Motor cranks up without any problems....

 

[Laddies]

Re: Help, No Fire On Two Cylinders...

The trigger winding for 3 and 6 cyl is common, I think if you OHM test it you will find it open.

 

[Striper Rig]

Re: Help, No Fire On Two Cylinders...

The trigger winding for 3 and 6 cyl is common, I think if you OHM test it you will find it open.

I'm not sure where to look for what you're talking about, what do u mean find it open?

If this is the problem is it expensive to fix?

Where is the trigger winding?

 

[j_martin]

Re: Help, No Fire On Two Cylinders...

I'm not sure where to look for what you're talking about, what do u mean find it open?

If this is the problem is it expensive to fix?

Where is the trigger winding?

Just get a manufacturer's maintenance manual for your engine. It's difficult to converse when you don't know the nomenclature. (names of parts, etc.)

It's actually pretty simple, and the test procedures and repair procedures, including synchronization are all in the book.

hope it helps
John

 

[Striper Rig]

Re: Help, No Fire On Two Cylinders...

I was wondering if he is talking about the stator in the flywheel..when he says trigger winding....Is this where the trigger winding is located...Help...

J Martin, I will get a manual as soon as I can....


Thanks for help....

 

[Laddies]

Re: Help, No Fire On Two Cylinders...

The stator is the outside fixed winding under the flywheel the trigger is the inside movable group of windings on the inside of the stator. Go to the switch box and remove the trigger wires for 3 and 6 and test them with a ohm meter.

 

[Striper Rig]

Re: Help, No Fire On Two Cylinders...

Thanks Laddies...

I took the stator off today, it looks like it has been hot...

I will check the wires to the trigger tomorrow...

Thanks abunchey.....

And I will try not to move anything to get the timing off on the motor....

 

[gmacrae]

Re: Help, No Fire On Two Cylinders...

Same thing was happening on mine, 2 of the 6 sparks dead, new trigger coils sorted it. The part cost me about $300ish NZ - probably about $250US.

I've read that a faulty switchbox can cause the same symptom tho... is this right merc pros?

 

[j_martin]

Re: Help, No Fire On Two Cylinders...

Thanks Laddies...

I took the stator off today, it looks like it has been hot...

I will check the wires to the trigger tomorrow...

Thanks abunchey.....

And I will try not to move anything to get the timing off on the motor....

Get the book and do a link n sync on it when you put it back together. It isn't worth it to fry a power head cutting corners.

 

[Laddies]

Re: Help, No Fire On Two Cylinders...

Here's the test from CDI