Will not fire!!

[Austin0117]

I am having some troubles getting my boat to start. It turns over just fine will fire then die. If i keep the key in the start position it will run off the starter, only tried this for a second or 2. It acts like the kill switch is in the off position, (which it is not). I have a 2006 Tahoe Q4S w/ 4.3 V-6 220hp. I have changed ignition switch, checked plugs and wires, all harness connections. All i can think of is maybe the kill switch is bad...if that even happens or maybe new ignition coil. Any help would be greatly appreciated.

 

[Don S]

Re: Will not fire!!

Going to need a Merc serial number Austin, 2006 Tahoe Q4S w/ 4.3 V-6 220hp doesn't mean a thing for finding engine problems on MPI engines.

 

[Austin0117]

Re: Will not fire!!

SN is 0W386105

 

[Don S]

Re: Will not fire!!

Ok, carbed engine. Have you checked the kill switch to see if it works? Just because it's in the correct position doesn't mean it works.

 

[Austin0117]

Re: Will not fire!!

What is the correct way to check the kill switch? I haven't done any of this before.

 

[Bt Doctur]

Re: Will not fire!!

jumper it , or using a DVM check for 12V on each connection.

 

[Don S]

Re: Will not fire!!

jumper it , or using a DVM check for 12V on each connection.

Assuming you know how to use a DVM. Hook it up for a voltage test, not a voltage drop test. Hook it up wrong and you can get 12V. but it would mean the switch is bad.

 

[carribbean soul]

Re: Will not fire!!

check for loose or corded wires around coil and rotor

 

[Austin0117]

Re: Will not fire!!

is there a way to bypass the kill switch to see if it is the problem? I do not have a tester.

 

[Don S]

Re: Will not fire!!

is there a way to bypass the kill switch to see if it is the problem? I do not have a tester.

There is two purple wires going to and from the kill switch. Hook the two wires together and the switch is bypassed.

 

[Austin0117]

Re: Will not fire!!

OK, I have done that and the motor still won't stay running.

 

[dingdongs]

Re: Will not fire!!

could it be the faulty oil pressure switch not energising the fuel pump unless cranking.jumper the terminals wires and see if it runs then.

 

[Don S]

Re: Will not fire!!

could it be the faulty oil pressure switch not energising the fuel pump unless cranking.jumper the terminals wires and see if it runs then.

Probably not. The engine would run for 10 to 20 seconds after starting because of the fuel in the carb. His engine is dieing when he first lets off the key.

Get a meter or test light. Hook the meter black lead or test light lead to a known good ground, then with the key in the run position (not start) confirm that you have good voltage or a light on your test light at the + terminal of the coil.

 

[Austin0117]

Re: Will not fire!!

I used a test light and it looks like the coil is bad. I will replace it and let you know. thanks.

 

[Bt Doctur]

Re: Will not fire!!

coil cant be bad if it runs, but if you want to throw part at it ,go ahead.
Instead of guessing you would be better off following the instructions given and report the results.

 

[Austin0117]

Re: Will not fire!!

it doesn't run

 

[Bt Doctur]

Re: Will not fire!!

the posts say it runs if you put gas down the carb

 

[Bt Doctur]

Re: Will not fire!!

place a jumper from the + battery to the + side of the coil and report back. it should stay running with the jumper.

 

[Don S]

Re: Will not fire!!

it doesn't run

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

I used a test light and it looks like the coil is bad.

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

 

[Bt Doctur]

Re: Will not fire!!

read post 18