dt65 won't go above 1300rpm

[BigJim]

I still can't get this motor to go to the high side. Here is everything I have done:
rebuilt all three carbs, rebuilt fuel pump, removed reed valves and inspected -perfect ,replaced fuel hose from portable fuel tank to motor, replaced the disconnect fitting at the motor, syncronized the carb linkage
and tested the throttle valve sensor and have a monitoring gauge on the motor.
The throttle valve sensor was tested static and while running. Both specs fell with in the specs . The running test was done manual and not in gear.
When the motor is put into gear and moved towards high rpms ,@ 1300rpms the motor shuts down. No warning lights of any type on the monitoring panel. The motor will start right back up . The engine is idling @ 750 rpms. Now with the motor not in gear, the rpm can be raised to wide open and the throttle valve sensor voltage will increase to 2.8volts. Need some help

[mphelle8vld]

Put an inductive timing light on it, take note of the timing at idle. See if the timing advances with rpm. Does the light continue flashing as it dies?

[BigJim]

Dt65

Thanks for the info. Which spark plug is number one ? How do i change the timing (if needed )

bigjim

[mphelle8vld]

Top cylinder, timing is controlled by CDI, can't be adjusted.

[BigJim]

did compression test ; 130lb 130lb 135lb connected up an inductive timing light-
light flashes until motor stops. how do I check to see if timing is advancing ?

[BigJim]

How do you hook up a tach/dwell/voltmeter (all in one ) to the dt65?
I was using a photo tach before . The meter has two wires,black and green. I know one goes to the battery, but where do I attach the green wire for rpms?

[mphelle8vld]

Don't think a dwell/tach will work.

There's a small window in the plastic cover over the flywheel, rotate the flywheel by hand clockwise until you see the timing marks, use a black sharpie to make a mark at 6 degrees AFTER TDC. That's the timing at idle on a warm motor. As you increase rpm the mark will move off to the right as the timing advances.

[BigJim]

thanks, my timing is advancing when rpm is increased..I have discovered another problem. After running the motor, I pulled my spark plugs . Found water mixed with oil on the plug in #3 cylinder. Now what ???

[mphelle8vld]

Not good, only two places water can get in combustion chamber, head gasket and exhaust cover gasket, (or cracked block but that would be less likely). If the motor has ever been overheated I would look at the head gasket first but both are notorious for twisting off bolts. Let us know what you find.

[BigJim]

I have decided to change both the head gasket and the exhaust gasket. It would not matter which one I picked to do, it would be the other one. So, should I remove the engine to do this work ?

[mphelle8vld]

Has the motor ever overheated? I would do the head gasket with the powerhead in place, if you see evidence of blowby on the gasket I would leave the exhaust cover and its bolts alone. If you can't get to it right away squirt some oil in #3 and spin it.

[BigJim]

The motor has never overheated.. so, remove the power head and replace the gasket while the motor is in place. ?

[mphelle8vld]

Take a look, I believe you can replace the head gasket with the powerhead in place.

[BigJim]

Are you talking about the cylinder head cover gasket or the gasket behind the head. My book says to remove five bolts for the cover and 18 bolts for the head. Now i am turned around..

[mphelle8vld]

18 bolts for the head, you will see if you need to remove cover to give more clearance.