trimming causes motor stumble

[twa72]

89 bayliner 19ft 2.3 omc First put it in the water and run about six mile upstream everything works great slow and wot. then when you trim up or down it causes the motor to miss but at only above 4200rpm maybe it does do it slower and i dont notice i dont know. Done the research and change the points and condenser (dwell the points at 32) changed the coil, checked the connections and that seemed to help a little bit but problem is still there. The after awhile running at 4500-4800 it will start to do that miss till I back out of the throttle.But that is only after I have been playing with the trim so much trying to figure it out. Any ideas would be greatly welcome!! Greta site whish I had found a couple of years ago!!!!!!!!!!!!

 

[Boatin Bob]

Re: trimming causes motor stumble

Most likely you have a bad connection somewhere at the battery or at the engine. When trimming it is dropping voltage somewhere and this is causing your miss as the ignition is starving for power. Check and clean all battery connections and at the engine end as well.

 

[rodbolt]

Re: trimming causes motor stumble

I am with boating bob<br /> ya got a bad connectiuon someplace. the trim is drawing more current than the system can supply.<br /> most likly corrosion on a pin or the battery wing nuts are finger tight.

 

[dhoptay]

Re: trimming causes motor stumble

could it be trim is to it's limit and putting load on the electrical system?

 

[sea wolf]

Re: trimming causes motor stumble

Check out your alternator.

 

[Lou C]

Re: trimming causes motor stumble

Replace the batt cables if there are old and use clamps with nylock nuts instead of the wing nuts. I replaced all the cables last year when I put in my dual batt system and it made a big difference, no more slow cranking problems.

 

[seahorse5]

Re: trimming causes motor stumble

That was a common problem on early model 4.3L motors.<br /><br />The fix for those included a separate 10 gauge gound wire from the alternator frame to the engine block. That also helps on models like yours.<br /><br />Also check the ground stud on the block, it is probably rusty along with the wire terminals attached to it.<br /><br />A weak or too low capacity battery can also be the culprit, as can poor battery connections and cables.

 

[twa72]

Re: trimming causes motor stumble

Went Boating yesterday did more research. Alternator is charging at 15.3 so no problem connections are good from battery to soleniod for starter and from alternator<br /> By the gause running at 14 hit trim it drops to 9 so definitely trim i think Had a buddy run it on land I think it is going real slow and even got stuck at on point and i picked it up to get it goin, while trimming up. There is no physical damage anywhere and the trim motor squealed a couple of times broke a line loos and there was fluid in it at motor<br /> Any suggestions or fixes can I replace motor or do i have to do pump and motor?<br /> Can not find my manual I purchased 4 years ago Thanks for all the help so far been checking what you guys have mentioned

 

[lowshovel1]

Re: trimming causes motor stumble

(Alternator is charging at 15.3)-------Sounds high,you sure batterys are good?

 

[drvred]

Re: trimming causes motor stumble

I just went through this same problem with my 140. It turned out to be the main electrical plug on the back of the motor. <br /> Pulled the plug, cleaned it with some electrical cleaner, and it ran fine afterwards.<br /> Two weeks later, had a miss that was unrelated to trimming. Turned out to be corrosion on the small terminals on the coil.<br /> Hope this helps.<br /><br /> Rick Edwards

 

[dhoptay]

Re: trimming causes motor stumble

check ground contacts make sure all are good