1975 15hp dropping a cylinder

[underpressure]

model is 15r75c ,went out on the water last weekend and motor was running perfect,after about 20 min of running ,it feels like it is dropping a cylinder,but it never stalled out ,just loss of power ,and after 5 seconds or so it was running fine again,and keeps repeating this cycle,so i purchased a new coil because one had been replaced allready before i got the motor,installed new coil and tried to start the motor, it would not start or it would just sputter,noticed that the spark was coming out from around the boot at the plug juming across the porcelian and grounding out on the shank of the plug,reinstalled the old coil and it didnt do it anymore,installed another new plug with new coil and the same thing ,spark coming from around boot to shank of plug,cannot get this to stop and have never seen this before ,hope its a good description and an easy fix ,im lost on this one,please help and thanks in advance for any help

 

[tashasdaddy]

Re: 1975 15hp dropping a cylinder

is this a put together type boot, or come as a completed unit. the put together strip back some insulation and wrap the wire around the spring to get a good connection, then slide the boot all the way on.

 

[underpressure]

Re: 1975 15hp dropping a cylinder

yes it is a put together type coil ,i will do as you suggested and see what happens ,should i use dielectric grease or none at all

 

[Rick.]

Re: 1975 15hp dropping a cylinder

A helpful hint from me. I have found some of the boots will pull the wire coil out of shape when trying to remove them. Get a cup of HOT water and let the boot sit in it for a minute and it will slide right off. A little dielectric grease won't hurt anything but if you do as TD says you will have a good connection. IMO. Rick.

 

[underpressure]

Re: 1975 15hp dropping a cylinder

went to the marina and purchased 2 new boots 1 for each coil ,the boot that was on the new coil was no good ,after i replaced them was able to spray them with water and the motor ran fine ,the problem is gone ,thanks for all the help