77 Evinrude 115 hp- Need advice on CDI replacement coil fitment

[Dixiedawg]

Hello, I have a 77 Evinrude 115 hp on my 1978, 17.5 ft McKee Craft Southporter. I purchased this motor in 2015 as a replacement for the original 79 100 hp, which was used in salt water by previous owners, and had lots of corrosion issues. I only use the boat in fresh water, and so I found this 115 hp which came off an old bass boat. The motor is in surprisingly good shape for a 43 year old motor. The most recent compression reading was...
#1: 136 psi. #2: 137 psi.
#3: 134 psi. #4: 136 psi.
This motor has served me very well so far. It did develop an intermittent spark issue on the 1 & 3 bank due to a failing power pack. I opted to go with the CDI power pack, as I read mostly good reviews. A couple of the old coils were also cracked, so I went ahead and bought 4 new CDI coils at the same time. The replacements are CDI 183-4632, per the CDI website. While I have them sort of mounted, and they work great, the shoulders on each side of the coils are much bulkier than the original coils, and I can only get 1 bolt into two of them due to the coils interfering with each other. Has anyone else run into this issue, and if so, how did you resolve it? I don't like running these this way, but i hate to start drilling out extra holes in the coil mounting plate. I always try to keep things as original as possible. I am attaching some photos (I think).
Thanks!

https://photos.app.goo.gl/LHaou1X6BQwbovnb6

 

[Dixiedawg]

Any thoughts on using a round file to elongate the mounting holes in the coils themselves, so that I can line them up with the prethreaded factory holes? Not sure if it would be a good idea to file that area of the coils.

 

[Dixiedawg]

Here are some more pics of the mounting holes.

 

[racerone]

Everybody works to different rules and buys parts from online sources I believe.-------I would install coils from say a much newer 8 HP or 115 HP FICHT motor.----The kind that is one neat assembly with both coils as one piece. !!!

 

[Dixiedawg]

Thanks for stopping in Racerone. I have gone way over my boat budget this year due to a trailer rebuild. Since these are brand new, paid for and the motor is running excellent with them, would you just leave them as I have them? I have been checking them occasionally to make sure that they are staying tight. Thanks again for your advice.

 

[McGR]

I'm fairly sure those are the wrong coils for that motor. I believe your motor had the earlier style coils (p/n 581610) as shown in the attached image. OMC changed the ignition system on these around 1977/78. Your coils look like the ones used in the later ignition system.

 

[Dixiedawg]

Thanks McGR. I am wondering the same thing. I did go on the CDI electronics website to confirm fitment prior to ordering these, but my originals were definitely shaped the same way as the ones you pictured. Oh well, the motor runs great with these, so I suppose that I will just regularly check the bolts and make sure that they are staying tight. I know that this is one of the downsides of aftermarket parts, just read lots of reviews recommending the cdi electronics components. Thanks again!

 

[flyingscott]

You do not have the wrong coils those are the updated version of the original coil. It is pretty well known about CDI coils having fitment issues. Do what Racer said or elongate the holes with a file.

 

[Dixiedawg]

Thanks for checking in flyingscott. I think that I will go ahead and elongate the holes slightly with a round file. I just wanted some confirmation from you guys that it wouldn't damage the coils or shorten their lifespan. Thanks again.

 

[McGR]

I think CDI should consider advising customers (i.e. instruction sheet) regarding the difference between their coils and OEMs and the required modifications. Do they somehow expect everyone to be "in the know"?

I've been working in aftermarket parts for 30+ years... Sometimes as an aftermarket supplier you have to offer what's available even if it is different from the OEM. BUT, in these cases you need to include documents explaining the difference. Doing things like this is just opening the door for unnecessary returned parts and unhappy customers.

 

[Dixiedawg]

Totally agree!