88 johnson v4 110 horse help !!

[Johnbel]

i have excellent top range motor runs good,checked compression,all 3 cylinders 100 then the last one was 85 changed the plugs too,the problem is when i move the throttle from start ,it bogs down if i move slowly it does not and will pick up speed like it should it does it every once in a while i also changed the water seperator filter too!!it seems to do it after the motor is warmed up,sometimes when it boggs down it will stall,when ever it bogs i move the throttle back then start again and it might not do it the second time,<br />please help!!the motor runs good starts good and once i get past the bog ,there is no loss of power at all<br />thanks in advance johnb

 

[emckelvy]

Re: 88 johnson v4 110 horse help !!

Check to make sure the timer base is not hanging up as you advance the throttle. It definitely will bog down if you don't get spark advance with the throttle. <br /><br />You can disconnect the timer base linkage from the throttle arm, then run it thru its range of motion and check for any binding.<br /><br />HTH........ed

 

[G DANE]

Re: 88 johnson v4 110 horse help !!

I would disassemble, soak and clean both carbs VERY carefully. After assembly, check floater hight , do a search on decarb and decarb it twice og tripple, might bring compression up on your low one, befor the carboning hurts cylinder walls and pistons. Do you have a manual to set ignition/trottle timing after refitting carbs ?

 

[DJ]

Re: 88 johnson v4 110 horse help !!

john,<br /><br />Your compression numbers do not look good. You have one cylinder that is very suspect. That cylinder can't pull its weight with low compresion.<br /><br />2-strokes can fool you on how well they will run with a sick cylinder.<br /><br />Here is what I would do.<br /><br />1. Check plugs. Do all the spark plugs look the same? Is one real clean looking?<br /><br />2. Recheck the compression numbers.<br /><br />3. Check the timing base advance, as suggested.<br /><br />4. Decarb. the engine.

 

[rodbolt]

Re: 88 johnson v4 110 horse help !!

remove the head. look at all the scars. cry a bit.<br /> but pull that head before you waste anymore time and money.<br /> good luck and keep posting

 

[Johnbel]

Re: 88 johnson v4 110 horse help !!

thanks to all will do will also update you<br />johnb