92 force 90

[catfishlion]

Hello all. I have a 92 bayliner with a 90 force motor.starts great idles great. When i put to full throttle it might get up to 18 mph.I rebuilt the carbs, replaced all fuel lines, did compression test, spark seems to be great. Pulled the prop off and had a shop look at it said was fine. I'm at a loss now. Any help or suggestions would be appreciated.
thanks

 

[catfishlion]

Hello,I have a 92 force 90 on my bayliner. Statrs and idles great. Once you go into forward runs great but will not get over 18? mph. I have done a compression test and was all good. rebuilt carbs,new fuel lines,spark seems to be great. Not sure what else to check. Oh and i took the prop off and to a shop and they said it was fine. Any suggestions would be great. I am not a boat engine guy at all lol.
Thanks

 

[catfishlion]

Do i have my settings wrong? I have no replies in the last few days.New so not sure im set up right

 

[GA_Boater]

It helps to start threads in the right forum section, which leads to getting replies.

You may not be a frequent poster, but you're not new after almost 7 1/2 years.

 

[catfishlion]

It helps to start threads in the right forum section, which leads to getting replies.

You may not be a frequent poster, but you're not new after almost 7 1/2 years.

I didn;t realize I did at first,appoligize, And yes this is only my second post in 7 1/2 years.lol

 

[The Force power]

Welcome back
-what are your compression readings?
- are all plugs firing? Check each cylinder for rpm drop, while in running idle
- is the fuel-pump inspected/rebuilt?
- did you check the spark with a spark-tester?
You may not be an boat engine guy, but you'll a few good testing tools are required when owning an outboard. lol

 

[jerryjerry05]

More info?
Does the motor continue to rev up after you get to 18mph?
You have Trim@Tilt ?
How big a load are you carrying?
Check / watch the linkage as you have someone push the throttle forward(turn prop as you push throttle, otherwise the linkage binds).
Watch the timer base as you throttle up.

 

[catfishlion]

Welcome back
-what are your compression readings?
- are all plugs firing? Check each cylinder for rpm drop, while in running idle
- is the fuel-pump inspected/rebuilt?
- did you check the spark with a spark-tester?
You may not be an boat engine guy, but you'll a few good testing tools are required when owning an outboard. lol

I did not check the fuel pump, holds rpm at wot , Compression was 120 120 115 115, Spark was tested just jumping plugs.

 

[catfishlion]

More info?
Does the motor continue to rev up after you get to 18mph?
You have Trim@Tilt ?
How big a load are you carrying?
Check / watch the linkage as you have someone push the throttle forward(turn prop as you push throttle, otherwise the linkage binds).
Watch the timer base as you throttle up.

It does not have power trim on it. all i carry is a cooler 3-4 people and a tube. So i wouldn't think weight was a problem.

 

[The Force power]

I did not check the fuel pump, holds rpm at wot , Compression was 120 120 115 115, Spark was tested just jumping plugs.

Are all plugs burning evenly? what are your max rpms reading under load?

While engine is idling; pull one plug-wire off the spark-plug & listen for a rpm drop.
IF with one of them you notice no drop in rpms; then that is the cylinder of the engine that not working

 

[catfishlion]

Are all plugs burning evenly? what are your max rpms reading under load?

While engine is idling; pull one plug-wire off the spark-plug & listen for a rpm drop.
IF with one of them you notice no drop in rpms; then that is the cylinder of the engine that not working

I did a drop on the plugs. All drop the rpm down when removed.My merc 85 would get on plane right away, this anchor takes about 100 yds to just barely plane.I appreciate the reply.

 

[jerryjerry05]

Your not answering all the questions??
(Does the motor continue to rev up after you get to 18mph?
Check / watch the linkage as you have someone push the throttle forward(turn prop as you push throttle, otherwise the linkage binds).
Watch the timer base as you throttle up.) Linkage broken?
How big a boat? Make model?
What rpms at wide open?

 

[catfishlion]

Your not answering all the questions??
(Does the motor continue to rev up after you get to 18mph?
Check / watch the linkage as you have someone push the throttle forward(turn prop as you push throttle, otherwise the linkage binds).
Watch the timer base as you throttle up.) Linkage broken?
How big a boat? Make model?
What rpms at wide open?

No, wot throttle rpm stay with the motor speed,No reving higher or anything. Linkage is intact. Its a 92 bayliner 19ft. rpms wide open are around 3500-3800. Thanks

 

[The Force power]

No, wot throttle rpm stay with the motor speed,No reving higher or anything. Linkage is intact. Its a 92 bayliner 19ft. rpms wide open are around 3500-3800. Thanks

As Jerry already mentioned; verify the timing is advancing to max in full throttle ALSO verify the shutters in the carbs. are fully open!
inspected/rebuilt the fuel pump otherwise we keep guessing

 

[catfishlion]

As Jerry already mentioned; verify the timing is advancing to max in full throttle ALSO verify the shutters in the carbs. are fully open!
inspected/rebuilt the fuel pump otherwise we keep guessing

I will check those this weekend. Thank you for the help!!!