55HP 2 stroke Yamaha Not Firing

[ChuckB1954]

The story of this motor is long and complicated, but I feel it needs to be told. It use to be on the boat I have now until the owners son blew it up.. The owner had it taken off, replacing it with a poor running Yamaha 50 Four Stroke. The owners son took the blown up motor and the poor running four stroke to a "repair shop". Nothing was resolved and although no one realized it at the time, both motors came back missing pieces. He gave the blown up 55HP two stroke to my friend, on the condition he try and repair the Yamaha 50 Four Stroke, which wasn't running right. Then the owner decide to just sell the boat and let my friend keep the 2 stroke anyway. It is the boat I bought. I made a thread about it running rich and about the parts missing.

My friend realized the 55HP 2 stroke was beyond economical repair so he bought a used, bare power head. He transferred all the parts ( carbs, electrical, electronic, etc) from the blown up motor to this one. He never could get it to run properly.. it never would idle or even continue to run.. After a bunch of mishaps, he threw in the towel. Another friend had already bought this engine from him, anticipating that it would be ready to go in a short time. It is now in my hands to get running. It halfway ran before, but now it wont even fire.. no spark.

I was surprised that this engine has two tags on it.. here is the numbers on the right side of the mount:


28733.jpeg


Here is the numbers on the left side of the mount:

28731.jpeg

So I purchased a manual for model C55TLRS, part number LIT-18616-00-43 It covers this model from 1991-1994. This engine is a 1994.

I could find no info on the model number on the right side of the mount. C550LRS

Now my problem. After some other troubleshooting, I attempted to OHM out the CDI with the chart shown in the manual I purchased:

CDI.JPG

The problem is that the CDI wiring on this engine is not the same as in the manual. Here is the cover plate from the CDI junction strip on this engine that reflects the colors:

20190602_184708small.JPG



What would explain this? Is this the wrong ignition for this engine, or did I get the wrong manual?

[99yam40]

maybe an after market CDI

[ChuckB1954]

maybe an after market CDI

That's an idea I haven't considered, although that cover plate sure looks factory, to me anyway. Maybe I can find some numbers on the CDI to determine it's origin and application.

[ChuckB1954]

Maybe I can ignore the colors by matching the components physically and tracing them in the schematic and still use the test chart(?)

[panasonic]

Should be some numbers on the CDI...post a picture. Mr Boscoe may be able to help you identify it. He is very good at that.

[panasonic]

Go here and enter your specifics

CDIELECTRONICS.COM

It will tell you which cdi their aftermarket one replaces.

They also have charts which give peak voltage inputs and outputs for many different engines.

[panasonic]

https://www.amazon.ca/Voltage-Readin.../dp/B00R3B6HYW

You need one these for your meter to measure peak voltages. This is the one I have.
CDI Electronics have them as well.

[ChuckB1954]

Go here and enter your specifics

CDIELECTRONICS.COM

It will tell you which cdi their aftermarket one replaces.

They also have charts which give peak voltage inputs and outputs for many different engines.

Well if that CDI is aftermarket, then all the components attached to it are also aftermarket (pulser coils, charge coil) because the leads from those components match the colors of the leads coming from the CDI. Seems unlikely.

[ChuckB1954]

Maybe I am over thinking this. I think I just need to find each component input and test it as per the chart. It shouldn't matter that all the colors don't match. The main ones do. It just confused me as to why this manual's is suppose to be for this motor and some wiring colors are different.

[panasonic]

Well if that CDI is aftermarket, then all the components attached to it are also aftermarket (pulser coils, charge coil) because the leads from those components match the colors of the leads coming from the CDI. Seems unlikely.

Sorry I never meant that it is a aftermarket CDI on your engine. They list an aftermarket CDI for that engine AND under the listing is all the Yamaha CDI it replaces. A bunch of Part numbers that may be on your CDI.

Also they have a troubleshooting guide which tells you how to test and what color wires to use. Check it out.

http://www.cdielectronics.com/support/

[panasonic]

I don't know why your manual is showing different colors, but the manuals are not always right unfortunately.

[panasonic]

The story of this motor is long and complicated, but I feel it needs to be told. It use to be on the boat I have now until the owners son blew it up.. The owner had it taken off, replacing it with a poor running Yamaha 50 Four Stroke. The owners son took the blown up motor and the poor running four stroke to a "repair shop". Nothing was resolved and although no one realized it at the time, both motors came back missing pieces. He gave the blown up 55HP two stroke to my friend, on the condition he try and repair the Yamaha 50 Four Stroke, which wasn't running right. Then the owner decide to just sell the boat and let my friend keep the 2 stroke anyway. It is the boat I bought. I made a thread about it running rich and about the parts missing.

My friend realized the 55HP 2 stroke was beyond economical repair so he bought a used, bare power head. He transferred all the parts ( carbs, electrical, electronic, etc) from the blown up motor to this one. He never could get it to run properly.. it never would idle or even continue to run.. After a bunch of mishaps, he threw in the towel. Another friend had already bought this engine from him, anticipating that it would be ready to go in a short time. It is now in my hands to get running. It halfway ran before, but now it wont even fire.. no spark.

I was surprised that this engine has two tags on it.. here is the numbers on the right side of the mount:


28733.jpeg


Here is the numbers on the left side of the mount:

28731.jpeg

So I purchased a manual for model C55TLRS, part number LIT-18616-00-43 It covers this model from 1991-1994. This engine is a 1994.

I could find no info on the model number on the right side of the mount. C550LRS

Now my problem. After some other troubleshooting, I attempted to OHM out the CDI with the chart shown in the manual I purchased:

CDI.JPG

The problem is that the CDI wiring on this engine is not the same as in the manual. Here is the cover plate from the CDI junction strip on this engine that reflects the colors:

20190602_184708small.JPG



What would explain this? Is this the wrong ignition for this engine, or did I get the wrong manual?

TIA02-12 is on the top right side of the chart above, I believe that is the CDI manufacturer part number. Is that number on your CDI?

[ChuckB1954]

TIA02-12 is on the top right side of the chart above, I believe that is the CDI manufacturer part number. Is that number on your CDI?

Thanks, I will check it out tonight.

[ChuckB1954]

I checked the CDI for numbers. It matches the chart. I also found the brown and blue wires from the charge coil going to the CDI to be an open circuit. I have a spare and will change it. Hopefully, It should correct the firing problem. How it got damaged is beyond me, but my friend, the previous owner of this engine, did pull the flywheel off a couple of times. He also broke one of the float tabs on the lower carb when he was cleaning them. Put it back together anyway. I told him it was unacceptable so he will be pay for a replacement. There are other issues with missing carb/advance linkage that I will also have to deal. He also cleaned the varnish off the pickup area of pulsar coils!!.. why is beyond me. In time, I hope to make everything right. My other friend who bought this engine paid way to much.


20190603_193155_small.JPG

[ChuckB1954]

Well, the spare charging coil I had turned out to be from a '95 model, which is completely different than the 94 and earlier models. Rarer than hens teeth, but I finally found the right charging coil on ebay. When installing it, the pulser coils had to be removed to gain access to the wire chase that the charging coil wires set in. I noticed the pulser coil brackets have slotted mounting holes that allows you to adjust their position. I marked them when I took them off, but how critical is the alignment? I see nothing about it in the Yamaha manual.