1985 DT65 Suzuki outboard bogging

[kinghogg]

I am new to the site and need help! I have a 1985 DT65 on a 19' Carolina Skiff that I just purchased. Cranks and idles perfect (since I rebuilt the carbs), runs fine without being under load but boggs down under load. I have tried everything and have read several post's on this site and it sounds like i've checked most things...
What seems wierd to me is that I can let my buddy drive the boat with the cowl off and use the choke flaps to cut the air intake by 50% and the motor picks up and runs great! It will run for as long as you desire working the throttle up and down (1000-3000 rpms). As long as the motor stays above 1000 rpm's you can get back into it and it runs great. I can put back into neutral and shift into gear, fine....trolls great. Advance the throttle and it wants to die. Use the flaps to shut the air in half and it picks up. I then open the flaps all the way and off we go again! Why will the motor run so good full throttle and trolling but won't get-up and go without restricting the air??

Thanks for any help!

 

[99yam40]

It is running too lean

 

[3rdMarDiv]

I have same motor with same problem. I have had it into my local Suzuki dealer and have also been in contact with Suzuki. Seems that this motor has had problems with crank seals. Over the winter we are going to open the power head and inspect the crank shaft. They have a place in Wisconsin that replaces the seals with new sealed bearings.

The motor starts and runs great on muffs, Under any load it bogs out. This happens as soon as it is placed into either forward or reverse gear,

Compression is at 135 and 136 psi and leak down is at 7 and 8%. Everything is showing it as a great motor.

Complete rebuild on carbs with new jets, new thermostat, all new hoses, electrical all checks out, etc.

The dealer is not the only place I have info about the crank seals from.

What is your compression results? I would like to know in order to compare with mine...Thanks