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35 hp motor no spark

Fishman479

New member
Hey all,
I use to work a lot of these older motors but I was always under 25 hp. This is my first time with this many wires. Is there a power needed to make this work or how would you start tracking down the lack of spark? Model number from the freeze plug is E35RCRR. Any and all help is appreciated. note yes i realize the plug wires are disconnected from the plugs thats because i was testing for spark which there is none.







 
That motor is the same as the 20/25/28/30 blocks. How are you testing spark? Try disconnecting the black/yellow wire from the switch box.
 
That motor is the same as the 20/25/28/30 blocks. How are you testing spark? Try disconnecting the black/yellow wire from the switch box.

Checked 3 ways first out a timing light on and it wouldn't light second took out spark plugs held on a good ground point and watched no spark last stuck a screw driver in the plug boot and held close to a ground and no spark.

What are you calling the switch box?
 
Same as the power pack. Merc calls 'em a switch box.....I call 'em "trouble". When did you loose spark?
 
The powerpack ( AKA switchbox )-----Is the wee black item that says CD2 on it.----And 12 volts is not needed to make this motor run.
 
The powerpack ( AKA switchbox )-----Is the wee black item that says CD2 on it.----And 12 volts is not needed to make this motor run.

Thanks. This is the first motor I have dealt with that had that all my previous dealings the coils and everything were under the flywheel.
 
Hey Racer, thanks for your help. Now with Joe gone you really gotta bear the load. That PP is problematic in these years, and I've had 'em fail just from sitting over the winter. Since it has no spark on either cylinder and if you have checked output using CDI free diagnostics on-line manual, also tried Mr. Scott's suggestion to rule out a short in kill switch, it is probably this unit. Tim's Outboard in Hackensack MN has a good used one....I have got many from them 218 682 2331, Mike or Dan. These can become problematic especially when exposed to temperature extremes. In remote Ontario, I keep a spare in my "to go" box when I travel. A new one on Marine Engine is pretty good price too. Depends what you want to sink into it. Better tighten that recoil spring too.
 
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The cdi ignition is a vast improvement over the previous 2 systems it replaced. 9 out of 10 times spark loss is.because the powerpak went bad. A 3/8 wrench or socket and it can be replaced in less than 10 minutes. The external coils are far easier to test and service. I have used my motors in well below freezing and over 100 deg weather. I have never had a temperature related problem on those. The beauty of that ignition is the stuff under the flywheel very seldom goes bad. Don't be afraid of the ignition like others on this forum are, it is a tried and true ignition system. Get a manual and learn how that excellent system works. I highly recommend you do not buy a used pak you could get a bad one or one that is ready to go out. I dont know why people say they go bad on the shelf and then tell you to buy a.used.one.
 
My experience is when the motors are stored for the winter and we get -30 or -40. Go up in the springtime and no spark. So true, this extreme may not apply here. Mr. Scott, you are correct to say they are a great ignition system. Here in Duluth, it rarely gets below -20 and in my shop, not below -10. My 25's both have all original spark components and they are late 70's early 80's. The used ones that Tim's supplies are mostly replacements and their storage is much warmer than mine. The 35 hp here has the pack mounted where I don't like to see them.....right at the hottest part of the motor next to the exhaust cover. Let's wait and see what he finds, you might make a " monkey" out of me for sure. Certainly not the first time and probably not the last.
 
The power pak mounting spot stayed the same for pretty much the whole production run of those motors. I don't think that was an issue. Yes I.know.the 88-92 models.were under the flywheel
 
hey guys sorry i was in bed all day sunday sick as a dog. hopefully i will be able to dig into this motor more this week or next weekend. i am located down in oklahoma so i doubt this motor has seen the cold that timguy mentioned but maybe. thanks for the info and i will keep you updated.
 
Okay, take care and keep us posted. I learn more from being wrong than being "Wright"...... Still trying to figure out how they flew a 1050 pound aircraft with a 12 hp motor. Engineers today cannot duplicate what the Wright Bros. did over a century ago.
 
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Model number is for a rope start, but you show an electric start. Just a wild guess, perhaps whoever modified it has screwed up the wiring? Like connected 12V to the power pack?
 
The Wright Flier was completely restored by Orville and is now in the Smithsonian. It was severely damaged by a gust of wind on the day of man's first powered "heavier than air machine" flight.
 
yea my 95' 20hp only runs about 89 degrees on a cool day on the exhaust side. I think it's because of the high-volume water pump and big (for it's size) thermostat and cooling passages. on my 95', the pack is located on the lower port side near the exhaust . it did need to be replaced when i bought it, but it's failure probably had to do with how low it sits in the pan and kept getting wet from saltwater.
 
Model number is for a rope start, but you show an electric start. Just a wild guess, perhaps whoever modified it has screwed up the wiring? Like connected 12V to the power pack?

i put the electric starter on there as i am not for pulling that rope while trying to fix an unknown motor.
 
They are not the easiest motors to rope start. Many of the early ones had a decompresser. My Dad used to rope start his 40 Lark, he will get a new shoulder in his next life.
 
1980 35 evenrude no start , I pull the 3 wire plug and have signal coming from PP , have continuity from 3 wire plug to both coils , but when I plug it up , NOTHING , disconnected Black/yellow at 3 wire plug and on ignition switch , STUMPED
 
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