Ignition problems w/ 4.3 v6 Mercruiser- one bank not functioning...

[Orange_Spitfire]

I have a 92-93 Mercruiser V6 installed in a 95 Bayliner 2355 Capri and the new motor is almost perfect; maybe... I get clinders 2,4,and 6 to fire with no problems but 1,3, and 5 seem to spark through the case of the plug instead of the electrode. Oddly enough, the boat seems to run fine after you get it moving at a decent speed and seems to smooth right out. Why would this be and what do I need to do to solve this problem?? Thanks in advance!!<br /><br />Rob

 

[Orange_Spitfire]

Re: Ignition problems w/ 4.3 v6 Mercruiser- one bank not functioning...

Does anybody have any ideas about this?? I really need help. Thanks in advance.<br />Rob

 

[Trent]

Re: Ignition problems w/ 4.3 v6 Mercruiser- one bank not functioning...

Missing your point? Explain a little more by what you mean... "case of the plug". Are you saying that its sparking thru the sparkplug wire boot that connects to the sparkplug?? If so...Replace sparkplug wires.

 

[Orange_Spitfire]

Re: Ignition problems w/ 4.3 v6 Mercruiser- one bank not functioning...

No, actually, it is sparking from the threaded part of thground source (ie the engine block) when I checked for spark. I've never seen that before. The wires do not arc or anything and it's only on the left bank of the motor. The right bank runs as smooth as silk and even the left will start to run smooth at a higher RPM. I checked the plugs and at idle, they're soaked because the electrode is not sparking. I believe that when the plugs are installed, they are shorting out directly to the engine block at idle / low RPM. Could this be a problem with the spark control or the device under the rotor (looks like a picture box setup)? I really appreciate the help. <br />Rob

 

[Bondo]

Re: Ignition problems w/ 4.3 v6 Mercruiser- one bank not functioning...

Put a New set of Plugs in it.....<br /><br />I think it's the Way you're checking them.... <br />The trigger,+ the module have Nothing to do with it..... If either of these were bad, the motor Wouldn't Run....

 

[P.V.]

Re: Ignition problems w/ 4.3 v6 Mercruiser- one bank not functioning...

I'm confused by your comments... But, if the integrity of all the spark plug wires is not in doubt, and you've install'd the newest spark plugs and it still does as you describe, I would suspect the bushings in the dist. I've had 3 different boats this year with bad bushings. The symptoms are not too diffferent from your description. I suggest you remove the dist. cap and grab the rotor. Is there any side play???

 

[Orange_Spitfire]

Re: Ignition problems w/ 4.3 v6 Mercruiser- one bank not functioning...

Sorry about my brief hiatus. work keeps me on the move... I'll check the rotor for side play. I never thought of that and I'll let you know if that helps. Thanks again for the advice and I'll keep you posted.\<br /><br />Rob

 

[kenimpzoom]

Re: Ignition problems w/ 4.3 v6 Mercruiser- one bank not functioning...

Do you have the coil polarity reversed?<br /><br />Have you moved one complete wire/plug from the working side and moved it to the non working side? That would eliminate the wire/plug as the problem.<br /><br />Ken