force 120 dies when put in gear

[fishonboat]

I just boaught a 1992 bayliner with a 1992 force 120 and it seems to have a problem with low RPMs It will idle in neutral but once its put in gear it just dies. I have adjusted the throttle screw so that it is reading 1000 rpms when in nuetral. If i through it in gear fast i can sometime get it to take off. once it starts moving it runs like a top through all ranges of RPMs. but as soon as i pull the throttle into nuetral and try to put it back in gear it dies again. I'm going on vacation this coming weekend and i wanted to take my boat but it's not looking good. <br /><br />Does anyone have any ideas? I had the Compression checked and it is good. I replaced all plugs and put in freash gas. still no change. any help would be great.

 

[The Marine Doctor]

Re: force 120 dies when put in gear

Have you adjusted the low speed jets?<br /><br />They should be set at roughly 1 1/4 to 1 1/2 turns.<br /><br />TMD

 

[eurolarva]

Re: force 120 dies when put in gear

If the idle adjust has no effect try this. When motor is idling put into forward gear. When motor starts to die try engaging the choke and see if it stops the motor from killing. If it does you probably need to clean the carbs. Wouldnt hurt to replace fuel lines and diaphram in fuel pump as well.

 

[fishonboat]

Re: force 120 dies when put in gear

Thanks for the reply TMD and euro. I did try cleaning the carbs and adjusting the idle screws. they are both about 1 1/2 out. I will try putting it in the water this coming thrusday to see if there is any change. the other thing i noticed is that there seem to be a lot of fuel and oil commig from the bottom carb(blowing out). the top carb is dry as a whisle. I'm guessing that this may be from the motor sputtering around and backfirng. any ideas?

 

[The Marine Doctor]

Re: force 120 dies when put in gear

If there is fuel blowing out through the carb, it's likely that you have a broken reed on that cyl.<br /><br />You might want to pull the carbs off and peek inside.<br /><br />TMD

 

[jim dozier]

Re: force 120 dies when put in gear

Is the fuel pump on this engine connected to the bottom cylinder? If so, you may have a hole in the inner fuel pump diaphragm which may me squirting fuel directly into the intake port of that cylinder causing it to be overly rich and not fire at idle. At higher speeds the increased fuel demand may overcome the leak and not be noticeable. Rebuild the fuel pump to fix.