DT65 Suzuki

[cholliday81]

I have a 1986 DT65 oil injected suzuki engine on my 1981 skeeter bass boat. The engine starts fine but the choke butterflys stay closed. With the boat in neutral (at idle) and manually opening the choke the engine revs up to red line. It does not stay at idle. When you put the boat in gear and give it gas the choke sill stays closed, and the engine starts missing and dies. If anyone knows anything about my problem please let me know. Thanks

 

[stylesabu]

Re: DT65 Suzuki

is the soliniod for the choke staying energized? either the linkage is binding or your getting power to choke soliniod when its not supposed to

 

[cholliday81]

Re: DT65 Suzuki

Thank you for replying, I got my test light out and checked two places. 1 the first connection for the solenoid ( no power ), then checked at the end of the wiring harness from the hand controls up front and still ( no power ). The linkages are free they move really easy. The power top end only has 3 hours on it so its all clean and fresh. Do you know how the choke operates? I think its operated by pushing the start key in and holding it. By the way I just got the boat when my father passed away so I dont know much about it. Does the solenoid get power when pressing the key(closing the butterflys) for the choke then opening when releasing the button? Thanks again for the reply.

 

[stylesabu]

Re: DT65 Suzuki

to engage choke,you are right push key in while cranking.I'm not sure, weathger pushing switch in de-energizes or energizes choke soliniod.you realy shouldn't need much choke once engine is warm or temps above 70 degrees

 

[cholliday81]

Re: DT65 Suzuki

Thanks for repling again. I did go and run a hot wire straight to the solenoid and it operated fine. So I think my problem is in my switch. I purchased a used side control with the whole wire harness all the way to the motor. I hope this solves my choke problem. I still dont know about my other though. I am not sure if you may know anything about it but I will try. When I had the boat running, with it in the neutral position idling, the choke was closed. I manually opened the choke and the engine reved up to wide open throghtle, would this indicate a carb problem? Maybe the low speed jets being cloged? Again thanks for the replys

 

[stylesabu]

Re: DT65 Suzuki

choke is only used to start the motor, once started use fast idle to warm motor

 

[99yam40]

Re: DT65 Suzuki

Are you confusing the choke butterflies with the throttle plate butterflies?
Opening the throttle butterflies to allow more air in is the only way to cause the motor to rev. that I know of.

 

[eli_lilly]

Re: DT65 Suzuki

Yeah, I think you're working the throttle butterflies and there is no choke, it uses an enrichment valve that squirts gas direct.

-E

 

[stylesabu]

Re: DT65 Suzuki

my dt 75 uses a choke soliniod, if chike plates are closed down most of the way engine will run very rich, idle will kick up some once plates are opened, but not over set idle speed

 

[cholliday81]

Re: DT65 Suzuki

Thank you all for replying. Yes I am sure what I am looking at is the choke butterflys. The outer set is the choke all three are connected together and only connect to the choke solenoid. The second set are behind the choke butterflys and are connected to my throghtle cable. Its really weird but like I said when I manually open the choke it doesnt just pick up a little the engine goes from low idle to max rpms ( wide open ). To the point that I close them back because I dont want to hurt the engine. What even confuses me more is that the throghtle butterflys are still mostly closed, like it sould be idling. It will continue to run like that until you close the choke back and make it die. The first time I had this happen it scarred me and I turned the ignition switch off and the engine still was going, Then I pulled all the spark plug wires off and sill was going, pulled the cables off the battery and guess IT WAS STILL GOING! I finally closed the choke and it died. My head hurts from scratching it so much out there messing with it! Look forward to hearing back from you guys. Thanks for the help.

 

[99yam40]

Re: DT65 Suzuki

I can understand a motor not needing the battery to run and the key switch/ kill circuit going bad, but I have never seen a motor run without spark plug wires hooked up.
And a motor running high RPM with the throttle butterflies closed is a new one for me also.

 

[stylesabu]

Re: DT65 Suzuki

sounds like your throttle plates are stuck open, and your choke plates are acting as throttle plates.

 

[mphelle8vld]

Re: DT65 Suzuki

I can understand a motor not needing the battery to run and the key switch/ kill circuit going bad, but I have never seen a motor run without spark plug wires hooked up.
And a motor running high RPM with the throttle butterflies closed is a new one for me also.

Think of a model airplane with glowplug ignition, hook up power to the glowplug to heat it up, start the motor and remove power. The glowplug stays hot from the heat of combustion. It's the same for a 2 stroke outboard with a little carbon build up in the head, the carbon gets hot and pre-ignites the mixture, especially a lean mixture, which is why it continued to runaway without plugs.
He says in his last post that the throttle plates are not fully closed, more than enough for an unloaded motor to start screaming.
Clean the carburators, adjust the linkage, find out why your chokeplate is constantly closed.

 

[cholliday81]

Re: DT65 Suzuki

Ok I will pull the carbs off and clean them. Thanks for the info guys, will write again after I try this.

 

[cholliday81]

Re: DT65 Suzuki

Thanks guys for all your replys. I found my problems. It was a headache but got there. My middle carb had a peice of trash in one of the small jet holes, the other carbs looked good but cleaned them too. I think that was part of my problem. The main problem was my ignition switch. My choke was operating backwards because it wasn't getting power but instead power was running thru the ground which was making it work opposite from normal. The electronics on the motor all had power thru the grounds which juast made it go crazy. After changing the ignition switch, wiring harness and cleaning the carbs the engine starts and runs great. Again thank you for all of your input hopefully this might help somone else who has the same problem. One more thing I bought my ignition switch from NAPA auto parts which saved me about $100.00 and bought the wire harness and side contols off of ebay for $10.00. The local suzuki dealer helped me out with the color codes, so it didnt cost me much. If anyone has this problem check those places out.

 

[99yam40]

Re: DT65 Suzuki

Kind of sounds like the battery was installed backwards if grounds had 12 + on them or a bad negative cable connection, depending on how you tested.

 

[cholliday81]

Re: DT65 Suzuki

No the battery was installed correctly, the ignition switch was bad and was sending some power thru the grounds. Not fully 12v but enough to make all the electronics go wild. I am mechanicaly inclined but never have worked on a outboard. The owner of the local suzuki dealership which has been there for 37 years helped me out alot, he has seen this before. I hope this doesnt happen to anyone else because its a headache to figure out on your own. Thanks again guys.