tidechaser 1
Seaman
- Joined
- Jan 29, 2012
- Messages
- 62
recently bought a used 75 hp. merc 03' 2 stroke..the dealer had done the water pump,plugs,filters,fluid change etc..i bought it as is..gulp.
now i find the carbs were full of junk and i got rebuild kits..paid a merc. mechanic to clean and rebuild them..and i put everything back together.
i took it out and it got up on plane quick..then rpm's dropped and then surged up and down never getting as high as when first on plane.
i took everything apart again,found a couple of clamps loose enough to leak when pumping the ball hard.
took it for a ride again..better but it still will not get full rpm's without surging above maybe 19 mph..lower rpms it does it less.
so..i got a fuel pump kit and replaced the entire pump and hoses and clamps..i have run it on the hose but not in the water yet..however..what i notice is that if i hold rpm's at midrange the rpm's climb a bit then it backfires a little and then goes lower rpm and does the same thing over and over.
one more thing i noticed..if you put a rag over the carbs the top 2 will make it almost die but the bottom one does nat make as much of a difference. my sujuki 55 seemed to be the same though..and i had rebuilt the carbs on that engine as well..weird.
it was doing this very badly before i did the hoses and pump..now it is much more subtle.
so..my question is what does this seem to be most likely?
i have squirted carb cleaning around looking for leaks (rpm change) but there is almost no change in rpms.
also replaced the plugs the last time i took it out and it didnt seem to make a difference.
i will try and test it in the water next weekend but it does not seem right still.
thanks!
now i find the carbs were full of junk and i got rebuild kits..paid a merc. mechanic to clean and rebuild them..and i put everything back together.
i took it out and it got up on plane quick..then rpm's dropped and then surged up and down never getting as high as when first on plane.
i took everything apart again,found a couple of clamps loose enough to leak when pumping the ball hard.
took it for a ride again..better but it still will not get full rpm's without surging above maybe 19 mph..lower rpms it does it less.
so..i got a fuel pump kit and replaced the entire pump and hoses and clamps..i have run it on the hose but not in the water yet..however..what i notice is that if i hold rpm's at midrange the rpm's climb a bit then it backfires a little and then goes lower rpm and does the same thing over and over.
one more thing i noticed..if you put a rag over the carbs the top 2 will make it almost die but the bottom one does nat make as much of a difference. my sujuki 55 seemed to be the same though..and i had rebuilt the carbs on that engine as well..weird.
it was doing this very badly before i did the hoses and pump..now it is much more subtle.
so..my question is what does this seem to be most likely?
i have squirted carb cleaning around looking for leaks (rpm change) but there is almost no change in rpms.
also replaced the plugs the last time i took it out and it didnt seem to make a difference.
i will try and test it in the water next weekend but it does not seem right still.
thanks!