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View Full Version : Backing off throttle and boat stability question.



JayZ
06-13-2013, 02:05 PM
I am still learning to drive my 22 and have a question.

When I am running on plane say somewhere north of 60 and I back the throttle down the boat seems like it wants to twist to port.

Is this common or normal?

seabuddy
06-13-2013, 02:31 PM
Do you have a little tab on your lower unit behind the prop?

Greg K
06-13-2013, 02:39 PM
Pretty common depending on how fast you cut back on the throttle.


I am still learning to drive my 22 and have a question.

When I am running on plane say somewhere north of 60 and I back the throttle down the boat seems like it wants to twist to port.

Is this common or normal?

JayZ
06-13-2013, 02:44 PM
Pretty common depending on how fast you cut back on the throttle.

Thanks.

Vacuum secondaries that seem to close up pretty quickly. I may need to adjust them.

MOP
06-13-2013, 02:47 PM
Normal action! When the power is on the props torque tries to roll the boat away from direction of rotation, when you throttle down quickly the the torque swaps in the other direction. Only happens when the throttle is chopped!

biggiefl
06-13-2013, 02:54 PM
Just like with a car, you don't want to pull it back at high speed. It can also stress some areas as now the prop is trying to turn 800rpm when it should be at 4000+. Not saying you are gonna blow anything up but it is not helping anything either.

JayZ
06-13-2013, 03:20 PM
The off throttle response on my set up is not real linear. I dont just rip the throttle back but It feels like I do. ...you can hear the carb kind of whisle when coming off throttle.

biggiefl
06-13-2013, 03:51 PM
Go through the carb again. If a Quadrabog a rebuild kit is under $20...Webers are a rip at like $75. If it was done within a year you should be able to use the current gaskets and skip the kit.

JayZ
06-13-2013, 04:01 PM
Brand new off the shelf Holley 4160 780cfm.. ...maybe needs some tweaking. or I wonder if kit could be my throttle cable binding up or something?

Jraysray
06-13-2013, 07:37 PM
Happened to me as we'll. Will see if any different with the new 6.2.

JayZ
06-13-2013, 07:42 PM
Happened to me as we'll. Will see if any different with the new 6.2.

Hope you are getting close!

joseph m. hahnl
06-13-2013, 08:09 PM
Brand new off the shelf Holley 4160 780cfm.. ...maybe needs some tweaking. or I wonder if kit could be my throttle cable binding up or something?Could be the vacuum curve and the power valve is closing :checkered:

JayZ
06-13-2013, 09:53 PM
Could be the vacuum curve and the power valve is closing :checkered:

...thinking something like that. I am not a holley guy ...in fact I've never messed with anything but su side drafts or weber thriple throat down drafts so i need to read up on tuning these things.

Phil S
06-14-2013, 12:47 AM
Speaking my language.....listen to these guys though when it comes to driving a 22 with a marine carb.

mattyboy
06-14-2013, 06:23 AM
when chopping the throttle quickly like avoiding a collison with a weekend warrior on a jet ski my 16 would do a bit of a dance with some props and would pull one way with other props . The solas prop was like the boat had brakes it just slowed down. So that is a prop based issue.

now if your are pulling back on the stick slowly and it is not smooth or it acts like you slammed it back I would look to a mechanical resolution.

miike
06-14-2013, 09:56 AM
Ya mine does that too. Leans real hard to port at low speed when stopping too fast.

roadtrip se
06-14-2013, 10:33 AM
Unless you have to, don't do it. Easiest way to lunch a gear set. Think of it as the opposite of fireballing the throttle to get the boat on plane. Ton of stress on the drive train as a whole. Smooth, easy, and predictable....

Jraysray
06-14-2013, 11:24 AM
Hope you are getting close!

Its ready, just to sick to go get it.

RBT
06-14-2013, 12:53 PM
If your prop speed doesn't match your forward speed the blades on your prop become a rudder, naturally the quicker you decelerate the motor the more pronounced the effect.