Distributor Cap& Rotor Burnt

pcoyle24

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Joined
Jun 5, 2016
Messages
5
Have a 2001 glastron gx-205. Originally had a 5.0. Im the third owner of boat and due to improper winterization prior to owning it, i was stuck with a cracked block and taking water non stop and hydrolock. Had a 350 longblock put in and transfered all my other equipment over to this new motor. Had a issue with speaker wires and burning the cap and rotor. Problem solved by eliminating the wakeboard tower speakers. I have a sub and amp hooked up with the 4 inside boat speakers going. All has been fine all summer since end of may. Took it out this past weekend and was wakeboardi g and felt the boat stumble on takeoff pulling out of water. Made it back to marina pulled the cap and all inside looks like each point is burned and my rotor is done the same way. It has the updated id ition module with the flame thrower coil. Any ideas on where to start? Checked the ground from the battery to the side of block and all seems snug and tight. Idk if its a faulty distributor or what. First post on here and im by no means a boat engine mechanic.
 

gbeltran

Petty Officer 1st Class
Joined
Jul 12, 2009
Messages
283
I doubt the speakers had anything to do with the cap rotor issue. Post a pic, you know they do get that way, a lot of current flows/arcs across them to fire the plug. Are you using a cap with brass or aluminum contacts? How about your wires, how old and what kind? Is that distributor marine rated? As in mostly sealed or is it possible moisture collects in there? What distributor is it? Sorry about the multitude of questions, but it sounds like you have some aftermarket stuff for the ignition.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,614
What distributor do you have in this? Sounds like you don't have the original distributor.
 

pcoyle24

Recruit
Joined
Jun 5, 2016
Messages
5
The boat mechanic swapped the distributor out because my original one would do the same thing, and would only get spark on half the cylinders. He had this one in another engine that he had out of a boat and we put it in and everything has been fine since may. Now i went to use it one more time before winterizing and it messes up. It had the points sytem and was updated before i bought the boat with the flamethrower coil and ignition module on the distributor. This sytem has been a nightmare for me since owning the boat.
 

CraigBarnard

Petty Officer 1st Class
Joined
Nov 7, 2010
Messages
269
Without looking at the actual engine in person it sounds to me like you have high resistance in the secondary ignition. (Plugs. Wires).
If the wires or plugs have high reistance then the coil has to put out an excessive amount of voltage to overcome it. Causing to much "heat" inside the cap where the spark jumps from rotor to cap.
If not already done properly i would change the plugs (correct type and gap) and good OE wires.
Oh and i would be inclined to ditch the aftermarket coil. If its a stock engine they are a complete waste of time as a coil only puts out as much voltage as the system requires. A stock engine only needs a stock coil.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
51,234
Your 2001 should not have had points. Volvo wuit using points in the mid 80's. I suggest getting the right dizzy and ignition for your boat and motor.

I understand that you went from a 5.0 to a 5.7, however the dizzy should still be stock volvo. Most likely a delco est

If your "mechanic" swapped in an old dizzy, get a new mechanic
 

pcoyle24

Recruit
Joined
Jun 5, 2016
Messages
5
Appreciate it guys. Im not sure which distributor my engine calls for with it being a new engine and size. Apparently i have the wrong one now so i cant use that part number to get a new one. What direction do i go with to getting the correct one and new plugs and wires?
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,614
What is the model number for your engine? Was the original engine red or charcoal grey? You can probably tell by what the transom housing on the inside is.
 

pcoyle24

Recruit
Joined
Jun 5, 2016
Messages
5
Idk bonestly. It had a 5.0 from the factory. The previous owner put a 5.7 in it and didnt winterize it and ive put another long block in it. Makes the 3rd engine in it so as far as knowing the color i couldnt tell you.
 
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