I recently purchased a '78 9.9 HP Evinrude with a 15 HP carb. It's my understanding the 9.9 and 15 HP motors of those years where the same exact engines with different carbs. I bought the engine back in January and it started just fine. Did all the basic checks; compression was 100 on the top cylinder and 97 on the bottom. Fuel lines looked great and where not cracked, PO installed a 15 HP carb and cleaned. PO installed a new water pump and impeller and provided proof with reciept and old water pump and impeller. Oil in the lower unit looked great. Started up fine and purred like a kitten.
Before doing a cold start last week for the first time this season me and a buddy checked the spark plugs to see if they where fine. Bottom spark plug had some junk in it so we replaced both spark plugs with the appropriate champions. . . we where having problems with getting the new lower spark plug to spark. Buddies dad walked in and finagled with the wires a bit, disconnected the wires running from the two coils to the powerpack(?) where the boot was at and moved the wires around. Eventually we where able to get the bottom plug to spark and after that it started right up fine on both cylinders.
Both Coils look corroded where the metal brackets are and the fact that the bottom plug wouldn't start up right away at first even when it was fresh doesn't seem like a good sign. I've been researching on youtube for a how to video on how to replace the coils and I can't find anything. There's information on just about everything else though. . . .
Did some research and I found out this was the replacement part.
http://www.iboats.com/mall/partfinde...n_id=320944695
Is this really the replacement part? I can see the boot for the spark plug, but the coils on my model are round. . .
I don't understand why there are different replacement parts for the 9.9 and 15 HP motors when they're basically the same motor with different carbs? I don't really have much know how when it comes to doing maintenance on these outboards but I'd like to learn. . . I've looked at a few different topics related to the issue around here and I've seen some unanswered questions that me and my buddy where also wondering about. We noticed that there where a set of wires coming from both of the coils going into a boot and we weren't sure how to replace on coil at that point without replacing the other. . . not that I'm against replacing both. I've run into some other potential issues mentioned on these forums including the fact that you have to align the coils correctly and that these replacement parts don't fit on that well and you need to kind of make it work using a bigger bolt. . . ?
If there's anyone who could point me in the right direction I'd appreciate it! I'm also going to look up the model number of my engine and take pictures of the coils to give you guys a look. . . .I've got a week long camping trip coming up this summer and I really want a reliable motor at that point. Right now if I have an issue the worst that would happen is I miss a day of fishing...
Edit: The coils look just like the picture in the original post of this topic, from a 78 25 HP evinrude
http://forums.iboats.com/forum/engi...ards/546705-78-johnson-25-hp-coil-replacement
As you can see in the picture both power wires go from the same boot into each coil. . . how do I replace one with out the other? Not sure how to insert new power lines into that boot. . .
Before doing a cold start last week for the first time this season me and a buddy checked the spark plugs to see if they where fine. Bottom spark plug had some junk in it so we replaced both spark plugs with the appropriate champions. . . we where having problems with getting the new lower spark plug to spark. Buddies dad walked in and finagled with the wires a bit, disconnected the wires running from the two coils to the powerpack(?) where the boot was at and moved the wires around. Eventually we where able to get the bottom plug to spark and after that it started right up fine on both cylinders.
Both Coils look corroded where the metal brackets are and the fact that the bottom plug wouldn't start up right away at first even when it was fresh doesn't seem like a good sign. I've been researching on youtube for a how to video on how to replace the coils and I can't find anything. There's information on just about everything else though. . . .
Did some research and I found out this was the replacement part.
http://www.iboats.com/mall/partfinde...n_id=320944695
Is this really the replacement part? I can see the boot for the spark plug, but the coils on my model are round. . .
I don't understand why there are different replacement parts for the 9.9 and 15 HP motors when they're basically the same motor with different carbs? I don't really have much know how when it comes to doing maintenance on these outboards but I'd like to learn. . . I've looked at a few different topics related to the issue around here and I've seen some unanswered questions that me and my buddy where also wondering about. We noticed that there where a set of wires coming from both of the coils going into a boot and we weren't sure how to replace on coil at that point without replacing the other. . . not that I'm against replacing both. I've run into some other potential issues mentioned on these forums including the fact that you have to align the coils correctly and that these replacement parts don't fit on that well and you need to kind of make it work using a bigger bolt. . . ?
If there's anyone who could point me in the right direction I'd appreciate it! I'm also going to look up the model number of my engine and take pictures of the coils to give you guys a look. . . .I've got a week long camping trip coming up this summer and I really want a reliable motor at that point. Right now if I have an issue the worst that would happen is I miss a day of fishing...
Edit: The coils look just like the picture in the original post of this topic, from a 78 25 HP evinrude
http://forums.iboats.com/forum/engi...ards/546705-78-johnson-25-hp-coil-replacement
As you can see in the picture both power wires go from the same boot into each coil. . . how do I replace one with out the other? Not sure how to insert new power lines into that boot. . .
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