Throttle Cable

Volvo Penta 5.7 GSI's

After winter layup, I started both engines and both have this issue

When I push remote forward to give acceleration, thats fine. But when I de-accelerate by pulling back on handle to neutral it doesn't go all the way back to idle. I have to manually push it back to slow engine back to idle. I have sprayed with lubricant and worked it back and forth, which doesnt seem to help, how do I adjust?

Ok, bear with me.
Most throttle/shift cables, when set up correctly, are capable of a slight "over-travel". We want this to a small degree to ensure a complete shift, and/or complete throttle movement in either direction.

It sounds as though your throttle cables, when returning to idle, are not offering any over-travel..... possibly meaning that they are not closing the throttle plates to idle position.
It may be as simple as an adjustment that offers a slight over-travel in the direction of "throttle closed".
Not saying that this is IT.... since I can't see your engines, but it may be worth a shot!
Give that a try by disconnecting a throttle cable at the TBI, see if "throttle down" cable travel is capable of closing the throttle completely!
If not, make a very slight adjustment favoring the closed position.


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I will dig into this one tomorrow, thanks for the advice