more tn28 problems, lost high rpms but runs fine in a bucket

[greenygreen]

from the top, bought a tn28 2 years ago. it had new coils, impeller, gaskets and i rebuilt the carb. fuel lines clear and new spark plugs which i changed just before the problem and they were not the right plugs that came out . just put float in today but didnt change anything,. when i took it first trip this year the clutch spring was broken so i ran it for about 20 mins at idle then fixed the spring by using the 3/4 of it that was good. anyways when i put back in the lake i have lost all high rpms. NO sputtering just a steady 1000 rpms at most. im sure fuel system is good and compression was good. high speed needle and butterfly seem to be acting normal.RUNS GREAT IN A BUCKET but wont pick up when boating. i cant tell any difference in anything but rpm. purrs like a kitten just lost its growl. it used to plane the boat out with a 60lb battery in front..

 

[HighTrim]

Re: more tn28 problems, lost high rpms but runs fine in a bucket

Check to see if it is running on both cylinders. Pull one plug wire at a time. You should hear a noticeable drop in RPMS, if not, that cylinder was not running. Pulling the other wire, will likely kill it, as it was only running on that one.

 

[greenygreen]

Re: more tn28 problems, lost high rpms but runs fine in a bucket

i pulled plugs before running and the top plug is nasty oily and the bottom looked good and clean. no fire to the top i assume. where to go from here? i havent pulled the flywheel on this yet i guess im gonna get to.. i will test it running as you asked when it stops storming if i need too.

 

[greenygreen]

Re: more tn28 problems, lost high rpms but runs fine in a bucket

is a spark tester worth the 20 bucks or is manually testing just as good?

 

[greenygreen]

Re: more tn28 problems, lost high rpms but runs fine in a bucket

Ok i got a spark tester and confirmed am not getting fire to the top spark plug. if it is the wires is there any way to test and change them without removing the flywheel? or should i just go to coils and come foward? (still raining, workin under tarp!)

 

[oldcoot57]

Re: more tn28 problems, lost high rpms but runs fine in a bucket

I would try replacing the oily plug and try again. It's possible you got a bad new plug or cracked it during installation.

 

[greenygreen]

Re: more tn28 problems, lost high rpms but runs fine in a bucket

i swapped the plugs and both the plugs fired properly on the bottom cylinder

 

[greenygreen]

Re: more tn28 problems, lost high rpms but runs fine in a bucket

looks good and clean inside , hopefully its the wires, ive always thought they didnt look to great... off to get a harmonic balance puller for flywheel removal unless anyone has a better way to get em off

 

[greenygreen]

Re: more tn28 problems, lost high rpms but runs fine in a bucket

hey greenygreen make sure to get bolts that fit in your flywheel so you dont have to drive 30 mins back to town!

 

[greenygreen]

Re: more tn28 problems, lost high rpms but runs fine in a bucket

hey ok greeny green thanks for that advice!

 

[greenygreen]

Re: more tn28 problems, lost high rpms but runs fine in a bucket

yep no prob bud

 

[Triangleboater]

Re: more tn28 problems, lost high rpms but runs fine in a bucket

Guess you have to drive back into town?