1995 DT30C low troll issues

yyequipment · #1 (**permalink**) 10-12-2011, 08:43 PM

I have a very low hour 1995 DT30 (35 hours)that runs excellent at every speed except at about the 2 mph trolling speed. I ran compression on all cylinders and they are at 125 pounds +/- 2 pounds. The previous owner had the carbs professionaly rebuilt last year by a quality shop ( I have the reciept), I removed them and they look like new inside ( I cleaned them anyway). The problem I am having is the motor will run for about 3 seconds and then pop at the above metioned speed under load and will eventually die. I would appreciate any help this forum could offer. Thanks

boats.net · #2 (**permalink**) 10-13-2011, 08:36 AM

Verify that the carburetors are properly sinc'd and adjusted. The pop sound like it could be a lean pop due to improper adjustment.

yyequipment · #3 (**permalink**) 10-13-2011, 07:16 PM

Thanks, I sync the carbs as best I could by opening the the center carb butterfly .0030 via the idle screw and using a set of the old style carb feeler gauges (the round kind)to set the other two to the same spec. Sounds odd but it seems to have worked. Runs good and stopped popping thanks again for the help.

boats.net · #4 (**permalink**) 10-15-2011, 10:40 AM

An easier way to sync 2stroke engines is to back the idle adjustment screw all the way out (this closes all the butterflies) then loosen the individual carburetors butterfly screw (this will allow you to set the individual butterfly) allow the butterfly to close all the way then tighten the butterfly screw. Do this to all the carburetors. when completed tighten the idle adjustment screw till it starts to open butterflies, turn 1 turn. Start engine and adjust idle to 500-1000 rpms. You can then adjust the idle/air mixture screws. These need to be set at factory for beginning then adjusted accordingly.