Dt 225

[Marcus]

I own a DT225 and the last few times out after the engine warms up it will stall at idle or just out of idle. Runs fine on the top end and throughout the mid range. Is there a chance this could be bad plugs or more likely a thermostat or throttle sensor? Any help would be appreciated.

Thanks
Marcus

[RICHARD HARE]

I wish i had the answer for you. I have had this problem since i bought this motor and boat, used. I have heard that the thermostats might be bad and not letting the engine warm up enough. I replaced them and i could not even make the motor stall if i wanted. After 5 trips it was the same b.s. For the next year and is still not fixed. Some people say throttle position sensor and some people say adjust the idle. Only problem with this is half say you can and half say you can not adjust the idle speed. My engine idles about 600 rpms in nuetral. Let me know if you have any luck. If i figure it out fisrt ill let you know.

Rich

[smccar7467]

I had this issue and changed the throttle control sensor. Did the trick. However you just cannot throw it in. You must calibrate it correctly. Good Luck.

[plopez]

Similarities

I had similar troubles and it turned out to be a leaky head gasket left side. Pull your plugs and look for water. Then look for water in your fuel by removing the separator filter on your boat and dumping its contents into a bowl. If there is water then you have a bad filler cap or hose, leaky fuel tank or just a bad supply of fuel. Keep in mind if you like me tow the boat and fill up at roadside you are getting 10% ethanol. Ethanol is a moisture sponge so make sure the cap seal is good. My DT 225 would clunk at low speed then stall. I currently have the heads off and am waiting for parts. The whole thing including plugs do it yourself is under $250 with boats.net part. I'm sure it could be something else. Another test is to pinch the water hoses on the heads while you run it and feel for a "pulse". I was told there should not be one. if there is it blowing by the head gasket. Specially since I just re-did the water pump! By the way beware of breaking bolts! that will make the 2 hour job a 12 hour job! Heat is your friend here. Get a torch.
Just my 2 cents,
Glad to be here,
Plo