2002 DT225 loses spark on 3 cylinders after warm

[JJ6338]

i have a 2002, DT225 (2 stroke) that has 200 hours on it. it has always ran good with no issues. on my last two outings i have had an issue, once slow trolling and once running 3/4 throttle. the engine boggs and is only firing on the 3 port cylinders. no spark (i checked) during this problem. after waiting 45 minutes to an hour the motor runs like it should again. no alarms, buzzers etc.... any help is greatly appreciated.

[seaox230c]

Hi search for my post missing at speed by seaox230c....the only thing that takes out 3 cyls on the same side is a bad stator coil. I manufactures my own jumper harness and swapped the inputs and outputs of the coil and my dead bank shifted to the other side so I knew it was the stator...its odd that yours dies at high speed AND low speed because there are 2 separate coils...a high and low....mine only failed at high speed...I will try and look at the book tomorrow and see if there is anything that will kill both coils....you are sure about no spark at both speeds right?...How did you know

[JJ6338]

Hi search for my post missing at speed by seaox230c....the only thing that takes out 3 cyls on the same side is a bad stator coil. I manufactures my own jumper harness and swapped the inputs and outputs of the coil and my dead bank shifted to the other side so I knew it was the stator...its odd that yours dies at high speed AND low speed because there are 2 separate coils...a high and low....mine only failed at high speed...I will try and look at the book tomorrow and see if there is anything that will kill both coils....you are sure about no spark at both speeds right?...How did you know

I had a spare plug on the boat, pulled each plug wire and put plug on wire, grounded and looked for spark, no spark. If I crank the motor now it runs perfect. Run it a while, things warm up and loss of power , 7 mph top speed.

[Solarman]

A 2002 model may have a shift position sensor that could drop fire on one bank if not in the proper gear (thinks it's still in neutral).

Also, on the some of the newer dt motors, they had more features in heat sensors that also limited rpm's.

You need a good Suzuki service manual for your year motor. It should identify those additional features.

Good luck. Post back what you find out.

[seaox230c]

since your doing this by hand and die at low speeds its a low speed coil issue. I cant remember if they are bullet connectors or 1/8 spade connectors but you need a wiring print and the ability to splice some wires into a harness. there is a plus and minus on the low speed coil connectors you need to build a short harness with the proper connectors to switch the wires from the coil output to the cdi, If you do this and the same plugs are dead then the cdi is bad...if the opposite plug bank goes dead then your coil is bad...I will try to research the wiring print over the weekend to help you out

[JJ6338]

since your doing this by hand and die at low speeds its a low speed coil issue. I cant remember if they are bullet connectors or 1/8 spade connectors but you need a wiring print and the ability to splice some wires into a harness. there is a plus and minus on the low speed coil connectors you need to build a short harness with the proper connectors to switch the wires from the coil output to the cdi, If you do this and the same plugs are dead then the cdi is bad...if the opposite plug bank goes dead then your coil is bad...I will try to research the wiring print over the weekend to help you out

Thank you very much. Going to dig into it this weekend and see what I can find out.

[JJ6338]

A 2002 model may have a shift position sensor that could drop fire on one bank if not in the proper gear (thinks it's still in neutral).

Also, on the some of the newer dt motors, they had more features in heat sensors that also limited rpm's.

You need a good Suzuki service manual for your year motor. It should identify those additional features.

Good luck. Post back what you find out.

Thank you for the input. Digging in this weekend.

[JJ6338]

CDI Issue i believe

I have determined that this is a CDI issue. Ordered one and they sent me an ECM since I had it I tried it, didn't correct the issue. they are sending the CDI this week and I will install it and keep you posted.

[Solarman]

I am curious if you ever looked at the neutral switch? If the switch is stuck in neutral position, it would limit rpm's by grounding out one bank.

Good luck. Post back what you find.

[JJ6338]

I am curious if you ever looked at the neutral switch? If the switch is stuck in neutral position, it would limit rpm's by grounding out one bank.

Good luck. Post back what you find.

do not think it is an issue with any safety or neutral position sensors as the motor will rev to 1800 under load and well over 3000 in reverse or neutral with no load on it.

[baldbob]

do not think it is an issue with any safety or neutral position sensors as the motor will rev to 1800 under load and well over 3000 in reverse or neutral with no load on it.

I had this very same problem. After much found I tracked it to a bad capacitor on the ignition control board. There are two capacitors one for each side. The problem will be intermittent until the capacitor fails completely. The board is located behind the coil plate. Take that off and you'll see it

[JJ6338]

I had this very same problem. After much found I tracked it to a bad capacitor on the ignition control board. There are two capacitors one for each side. The problem will be intermittent until the capacitor fails completely. The board is located behind the coil plate. Take that off and you'll see it

Yeah it's the little square box they call the CDI. Thanks a ton!

[baldbob]

No problem

[JJ6338]

CDI was the issue

wanted to update the post so maybe it helps people in the future. the issue was the CDI box. all is good now.

thanks to all that assisted me.