55EL78S no fire on bottom cyl.

[OLDIRON]

Hey guys, hope you can help me with this.Just aquired a boat and 1978 55hp johnson.I try not to bug you and do a seach first, but this one has me baffeled.PO said it ran last year. But other then that, I have no history on it. I got without even hearing it run.It was a divorce, "I just need to get rid of it thing". Well it was pretty much free.Boat,motor,and trailer for just letting him get rid of it.But like my wife warned me,"there's no such thing as a free boat".
So here's my problem.This thing hasn't ran for a coulple of years.The po said it did run last time he took it to the lake.The first thing I noticed after I got it home has that someone had put a new coil on the bottom cyl. Before even trying to run it, I pulled both plugs and and noticed the top plug was pretty fouled, but the bottom looked good,a light tan colored.This is where it get's strange.After I charged the battery up and cranked it over, The top cyl. has great fire.The bottom has no fire.Eventhough it has the new coil.My guess is that someone had replaced the bottom coil and that didn't solve the problem. I ohmed out both coils and they checked out the same.I checked out all the connections and grounds and they are good.But I know nothing about CD ignition.I'm use to working on older Johnsons. Is it possible with CD that both coils could be ok, but only one fires? I do not have a service manual yet, but I am keeping an eye on ebay for one.If anyone can help me figure this problem out please let me know.Thanks.

 

[Black as]

Re: 55EL78S no fire on bottom cyl.

Have you checked the plugs that they all spark

 

[OLDIRON]

Re: 55EL78S no fire on bottom cyl.

Have you checked the plugs that they all spark

Yes.Tried both plugs on the top coil.They will spark only on the top coil,bottom coil...no spark.

 

[mikesea]

Re: 55EL78S no fire on bottom cyl.

you can swap the coils to insure both are ok,if coil is still ok ,I would think your powerpack has failed

 

[OLDIRON]

Re: 55EL78S no fire on bottom cyl.

Thanks Mike.I thought about that today so when I got home I swaped the leads to the coils and sure enought, both coils will fire on the number one wire coming from the cd pack.But neither will fire on the number two wire.So I guess that elimanates the coils. I don't want to throw parts at it, but if you think the cd pack is shot I don't mind spending 100 bucks on it. Is this the usual problem or do you think it could maybe be the pickup under the flywheel? Or both. Is there any way of testing the pack With a volt/ohm meter? Thanks for your reply.

 

[OLDIRON]

Re: 55EL78S no fire on bottom cyl.

OK.I did some more searching on this forum and found a CDI Electronics site that may help me. Looks like I need a DVA to test. I will have to get one.
The site tells me to check the timer base. Please forgive my ignorance, but what is a timer base? And what wires are they? Like I said, I can figure out how to get an older motor to run, but this cdi stuff has me baffeled. My main concern is to first do no harm. I'm hoping that it's just the power pack and nothing else.Thanks.

 

[72seastar]

Re: 55EL78S no fire on bottom cyl.

I have a 1972 Johnson 65 HP and i had a similar problem and even though it tells you its the timer base/stator or whatever you got up there it is more than likely the power pack i ripped everything up there to pieces only to find out it was the power pack.... now it very well may be the timer base or the stator but odds are your problem lies in the power pack

here is a website from johnson evinrude you can see schimatics and other things just go to the top left and select your make model year HP ect.

http://shop2.evinrude.com/ext/index.aspx?s1=5a81e668277ef0f68ae7f2a5d1f68be3

 

[OLDIRON]

Re: 55EL78S no fire on bottom cyl.

Today I checked everything I could without a DVA for my meter.Seems like it all ohms out according to specs. So that's a good sign and #1 does throw a wicked spark swaping both coils.I will try a local boat yard and see if he has a good used CD2 unit I can try.If that solves it, I will buy a new one.Thanks everyone for your help.
Modern motors, their way more dependable, but when they do go bad,nothing's cheap. Just like modern cars.

 

[mikesea]

Re: 55EL78S no fire on bottom cyl.

Im almost positive the pack from a 4 cyl will work ,if you happen to get one to try,I have every reason to believe its the pack,you did the tests,HOWEVER,I have come across some real crazy stuff with electrical components,packs do fail,if you do have a guy you can borrow one thats great,you may come across color differances in the pack wiring,the orange with blue or grn,blue would be top ,grn bottom,on a 4 cyl you may have 2 different colors,if you get a pack from a 4 cyl ,test the spark,if reverse ,you may get a backfire ,just reverse the plug wire if easier than the smll wires

 

[OLDIRON]

Re: 55EL78S no fire on bottom cyl.

Update. So I went down to the local shop.He dosn't work on OMC outboards anymore,hasn't for years. All he does now are I/O's.He didn't have a used one I could try, but he said that if you have spark on one cyl. it's 99.9% a cd pack to blame.So he scrounges around in his old inventory and finds a brand new pack that is NOS covered in dust and says I can have it for 70 bucks and he throws in a couple of new plugs. I put it on this morning and after and least two years, maybe more...SHE FIRED UP! I only had choke her and crank her over for like 10 seconds, and BAM! Now I'm gonna run some Seafoam through her with the old plugs, and then put the new ones in. One thing he did tell me is that eventhough I have one new coil, I should replace the top one also because from what he's seen, if a coil breaks down internally,it can flash back into the cd pack and may fry it. So I hope that advise helps someone here.Needless to say,I ordered a new top coil. Thanks for everyone's help here.Now I will be posting a new thread shortly with a few more questions about the care and feeding of this motor.