Idle control for 1999 Mercury 40hp 4 stroke

Kind of new to boat ownership. I’m looking for a idle control or cruise control for my 1999 Mercury 40hp four stroke tiller if there is such a thing. My boat is 2000 Lund 1650 Explorer. I have 12 volt trolling motors on the bow and stern, the bow mount is an i-pilot. They work great on lakes when I’m running them both for hands free navigation and speed control. My issue is when I’m on the river with a strong current there isn’t enough hp to troll at the speeds I want to go. I’d love to use the Merc to power the boat and the i-pilot for navigation. Any help would be appreciated.

Steve,check these guys out, https://trollmasters.com/
I see the biggest motor they list is a twenty hp but they do ask that you contact them if you dont see your motor listed.

Thanks, I think I saw that too when I was checking them out. I’ll say thanks again for helping me previously getting my motor fixed. I almost pm’d you asking this question. I figured you’d have some good ideas. I had a friend suggest that I try the throttle tension control and see if that’d hold the throttle in place. Have you ever heard of that working?

Well I guess I need to read the manual more often. There is a tension control knob for the throttle to control speed. I just thought it was for personal preference on how tight you wanted the tension on the throttle. I wish I had realized this a few years ago. Doesn’t hurt to read the manuals a few times I guess.

glad you figured it out !!
just remember to loosen it back up when using full throttle.