DF 140 Loss of RPM when Trimming Down

[Intuition Gloucester]

New DF 140 this weekend! Noticed that at speed (2000 RPM) the engine would lose about 400 RPM when I trimmed down. The loss would occur for only a second or two (for as long as I held the switch) and it would come back up to speed. No issues when tilting up. No issues at very low speed. Is this a safety feature?

 

[Triton II]

Re: DF 140 Loss of RPM when Trimming Down

New DF 140 this weekend! Noticed that at speed (2000 RPM) the engine would lose about 400 RPM when I trimmed down. The loss would occur for only a second or two (for as long as I held the switch) and it would come back up to speed. No issues when tilting up. No issues at very low speed. Is this a safety feature?

Congrats on your new OB. To answer your question. Nope, it isn't a safety feature. Most correctly rigged OBs lose rpms when trimmed down - especially if you're below your max torque rpm which for a DF140 is around 3500-4000rpm. However 400rpm is a fair loss, so I wonder if your motor is too high and you're prop is ventilating slightly when trimmed up and then bites when you trim down giving you a sudden loss of rpm. Then, as the boat accelerates, you gain back your rpm? Just a thought?

TII

 

[rodbolt]

Re: DF 140 Loss of RPM when Trimming Down

you have a battery connection or ground wire issue.
thats why the RPM comes back when you release the switch.
ALL the systems on that engine require constant 12V to work.
one of them isnt getting it when the down button is pushed.
take it back to the dealer.

 

[Intuition Gloucester]

Re: DF 140 Loss of RPM when Trimming Down

Marina mechanics have it today for a prop test and a electrical test. All new battery connections and cables as part of repower. I bet it's a ground.

Thanks

 

[krockett75]

Re: DF 140 Loss of RPM when Trimming Down

I am having the same exact problem with my 2009 Suzuki DF225. I cleaned and re-cleaned all battery connections and even replaced the battery switch. The problem went away and I used the boat 3 times with no issues. However the problem came back yesterday. Cleaned all battery connections again but no luck. Both times I had this problem I had given the boat a good washing and 2 days later my problem came about. Of course when I brought it to a Suzuki certified mechanic the problem went away on my way there and they found no trouble. Computer diagnostic test was perfect. Was curious if you or the dealer found a definite fix for what is causing this. Any help or info would be greatly appreciated. Thanks.