Will not fire!!

[Don S]

Re: Will not fire!!

It's carbed, and the engine runs with the key in the start position. It's not fuel.

Nice edit Doc, makes my answer to your MPI question you had look kind of silly.

 

[Bt Doctur]

Re: Will not fire!!

jumper to verify that the wiring is not supplying power to the coil in "run " position. I saw where he said if he holds the key on start it runs. work the problem back to the dash from the engine.

 

[Austin0117]

Re: Will not fire!!

You said it runs if you keep the key in the run position, so that alone says the coil works.




What was the result of the test? Did it light or not with the key on?

it did not light up with the key on.

 

[Don S]

Re: Will not fire!!

it did not light up with the key on.

Well if it didn't light up, then it's not the coils fault. The coil won't work until that terminal gets power.

Do as BT Doc mentioned and put a jumper from the positive battery cable to the + terminal of the coil and it will run. (remove the jumper to shut it off).

What you have to do is find out why you don't have power to the coils + terminal.

Since you replaced the switch, it could be anything from the ignition switch having a purple wire missing on the I termanil to a blown hidden fuse, or a bad kill switch, bad connection on a terminal somewhere, or ???????????

About that hidden fuse I mentioned, read this thread http://forums.iboats.com/mercruiser...den-fuse-4-3-tahoe-q4-please-help-554420.html
I don't think your engine is new enough for that fuse, but worth looking at to make sure.

 

[Austin0117]

Re: Will not fire!!

OK, I put a jumper to the coil and it's still will not run on its own.

 

[Don S]

Re: Will not fire!!

Did you read this thread.

http://forums.iboats.com/mercruiser...den-fuse-4-3-tahoe-q4-please-help-554420.html

 

[Don S]

Re: Will not fire!!

Pour some gas in the carb and see if it will start and run for a second or two after you let the key off.

 

[Austin0117]

Re: Will not fire!!

Sorry guys the wire wasn't connected good, it will run with the jumper to the coil.

 

[Don S]

Re: Will not fire!!

Then you have a problem somewhere in the purple wire from the key switch to + terminal of the coil. It can be a loose or corroded connection, broken wire, bad kill switch, etc., but it's in that wire somewhere.

 

[Austin0117]

Re: Will not fire!!

traced the purple wire all they way to the motor and the main connection going into the engine was almost falling off. I tightened it up and the boat fired right up. Even after tightening the connection as much as possible its still pretty loose is this a consistent problem with these motors and is there a fix to make it more secure.

 

[Don S]

Re: Will not fire!!

Even after tightening the connection as much as possible its still pretty loose is this a consistent problem with these motors and is there a fix to make it more secure.

If you are referring to the hose clamp on the round ten pin harness connector, then you have found your problem.
That clamp just gets snugged down a little to keep the connector from coming apart. If you have tightened it down as much as you can, then the connector is distorted and need to have both sides replaced.
If that is not the connector you are referring to, please post a picture. Might be a good idea either way, just to see what you are talking about.

 

[Austin0117]

Re: Will not fire!!

That is the connection I am talking about. If it needs to be replaced is that an easy part to find and replace? I don't have very big or helpful marine repair shops here.

 

[Don S]

Re: Will not fire!!

There are no pigtail replacement connectors for those. One is the end of the engine wiring harness, and the other goes to the instruments and ignition switch.
You might be able to take a helm extension harness and cut the ends off and splice them in to work. But the harness is expensive and it takes a lot of careful precise water proof splices to make it all work right.

 

[generator12]

Re: Will not fire!!

I know nothing about the specific ignition system you have, but what I've seen that relates to this situation is this:

Most ignition systems will provide full voltage to the coil in the "start" position, then revert to standard (reduced voltage) configuration when the key is released from "start" to "run". Essentially, there are different paths to the coil, one for start and one for run. If I had your problem I would look immediately at the ignition module, or whatever passes for that in your system.

 

[FreeBeeTony]

Re: Will not fire!!

If it's only that 1 wire in the connector you can do what I did.

I cut the wire at both sides of the connector and installed a "jumper wire" to bypass the big connector.
I used butt connectors/liquid electrical tape/shrink sleeving on the connections........

It'll work if it's just that 1 wire.........