02 200 HPDI dies when trim used

[yamayama]

i have an 02 yamaha 200 hpdi outboard with about 180 hours. Recently i ran into a bad gas problem and resolved that, changed ALL filters last year as well afterward. This year everything was running fine until now. When i used the trim while the motor is under stress it beings to bog down from say 3700 to 2500 rpms. Doesnt matter if you trim up or down, either direction does it. Also even while crusing through swells it has the same issues. I changed plugs and check battery grounds and all was well. Im at a loss

[rodbolt17]

keep checking cables and connections and the battery.
one of the 3 is your issue.
when the trim is used under load it draws more current than is availble.
when voltage drops so does the engine.
drop to much and it simply quits.

[yamayama]

Could it be the alt? after starting it i turned the battery switches off and the motor died after a few seconds

[rodbolt17]

could you have fried the charging system?
yep quite possible.
why ever bother the battery switchs with the engine running?
however its not the alt system thats killing the engine at trim use.
its low battery voltage for whatever reason.
what voltage is shown on the dash or the speedo when its idling?
should be 1.5-2.5 volts higher than with key on engine off.
if no speedo or voltmeter you can use a meter on the battery terminals.

[99yam40]

If a bad connection on a battery can cause charging system problems, then disconnecting one while it is running is a very bad idea. Hope yours is still good

[yamayama]

while running it settles around 13.6 volts at idle give or take +/- .2 . Anyone experience the reserve on the battery being to low? they're only a few months old, i dont remember the exact specs on them but i dont skimp on stuff for the boat. Running 2 btw.. and i dont think the charging system blew. only switched off for a few seconds.