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Question about plug gap and wires

1

1973browning

Contributing Member
I just installed the Pertronix

I just installed the Pertronix Flamethrower II coil and the Ignitor II electronic ignition on my 3.7lx 180hp. I did everything as directed as per instructions. Reset gap on plugs to .045 and set magnet to .030 as instructions said. The only thing that I have not replaced yet are the original 7mm wires to a new set of 8mm. My question is this: Will the 7mm wires allow enough voltage through the plugs with the .045 gap? The engine has spark and is trying to start but something is not right! Would the old 7mm wires possibly be the problem with the increased gap from .035 to .045? What do you guys think?
 
"I had no problems using old 7

"I had no problems using old 7mm wires, but one of the times I installed it a the peice around the dist shaft wasn't down all the way, and another time on another boat I didn't install the rotor."
 
"Ayuh,... Unless the wires ar

"Ayuh,... Unless the wires are Not passing power,..At All,...
You have Other Problems..."
 
Any spark plug wire will work

Any spark plug wire will work fine if new. I would reccomend a name brand over "walmart" quality.

Buying spark plug wires for a marine engine is different than automotive. Marine wires are much longer then automotive.

Also I would reset plug gap to no more than .040"

To wide of a gap could create other issues. .045 is a big gap with that engine.

The key to spark plug wires is the OHMS/FOOT rating. Most OEM are ~ 5000 ohms per foot. Many aftermarket quality wires are less but are not nessesary for your application.

I would buy OEM type replacement or go to a reputable Auto parts store that sells marine quality parts and order there.
 
"I too would suggest bringing

"I too would suggest bringing the gap a little bit tighter. Usually, the larger gaps are reserved for HEI systems.

Also, and just something to consider here..... if this Pertronix was a kit, some of them are known to be very sensitive to the Hall Effect magnetic unit and the Pick-Up unit alignment.
These are often a less precision type of triggering device that requires very close alignment.
See if the instructions address this as being a possible issue.
If so, then read up on how they want you to go about aligning the two.


."
 
"Thanks so much Brian,Bondo,kg

"Thanks so much Brian,Bondo,kghost and Ricardo! I did what you said kghost and Ricardo with the gap and finally got engine to fire and was idling nicely at around 650-750 rpms. I set the gap back to .035 and that seemed to help alot. I guess it would have helped if I changed the stupid wires(and they are original to the engine when I got it, so have no idea how old they are)lol The cap,wires and rotor are my next step. I think the .045 gap was just too much and don't think spark was able to jump that far. However, since regap I noticed a tremendous improvement! Idles smoother and you can hear it hitting on all four cylinders. I set timing with a light and really got it to idle nicely. I set it at about 5 degrees btdc and this seemed to be the sweet spot. Anyways, thanks again guys for the help! sincerely, Tom
P.S. I have another question about another issue and will start a new topic."
 
"Let me guess the next questio

"Let me guess the next question is about your carb ?.. adjusting the idle mixture to the proper setting "can" help if you feel the idle is a little rough, even playing with it a little you may find you can improve the idle more.. but there is a process.. and what's good on land isn't always good on the water and oh sorry.. another topic.. you can search the posts here for more information I know the processes has been mentioned alot."
 
"No Brian, I hope I am not pos

"No Brian, I hope I am not posting about my carb. lol Enough nonsense going at the moment! Thanks for the continued support! Tom"
 
I purcahsed a set of BELDEN 8

I purcahsed a set of BELDEN 8 mm marine wires from NAPA a few years ago for my boat.(1997 I think) and for many others over the years. Excelent wires!! Napa use to have a full marine parts catalouge. I do not know for sure if they still do. OEM are always good!!
 
"Thanks kghost for the info.,

"Thanks kghost for the info., I don't know if I did the right thing but I ordered the Pertronix 8mm universal delco 4cyl wire kit with one end straight and one end 90 degree end. I hope that is what I need. Anyways, thanks for the help! Oh, one more thing I found out about the distributor cap and rotor. I found out that GM used Delco Remy distributors on alot of the 4 and six cylinder engines of the 70's and I think 80's. Anyways, the rotor is the same on the four and six cylinders using the Delco (oem #58217-rotor) and I found the cap at an Autozone under 1970 Chevy Nova with a four cylinder 153cu. inch motor. lol They only had one left at another location so I guess that will be the last time that will happen. Just tired of the shipping charges on two items that total less than $12.00 I know where to get them online but they wanted to sell me the tune up kit which included the points and condensor which I hope I will no longer be needing. thanks, Tom"
 
"Well my experience with caps

"Well my experience with caps on boats is, they last a long time. I would say 300 + hours as long as they stay dry. If you have upgraded to a electronic ignition I would say it will be a while before you need another.

With electronic ignitons it is not uncommon for wires, plugs, caps to last at least 300 hrs minimum. The rotor will likely be the weak link.

With a point ignition everything works harder as the points degrade. Also more likely to have spark travel inside the cap with all that metal and arcing going on. Not the case with electronic ignitions."
 
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