Engine idles too high when coming out of gear - Mariner 40

alt · 16 May 2020, 23:49

Hi guys,
On my tender (Avon SR4), I have a Mariner 40 2-stroke auto-lube. (2000 - 2001)

When I start the engine, she idles fine. When I put her into gear and run at low RPM (not on the plane) and go back into neutral, she idles fine.

If i've been running on the plane / high RPM for some time and I then go back into neutral, it revs quite high. I don't have a tacho but i'm guessing approx 2000 RPM and stays like this.

I combat this by revving the engine with the idle-lever. I give it a quick blast of high(er) revs and then bring the lever back down. This brings the engine back to idle.

I'm at a total loss as to what the issue could be??

Ribtecer · 17 May 2020, 06:39

Something to do with the throttle cable not returning to it's rightful position I would have thought.

Sounds like your correcting that with the idle lever.

New cables or lubricating the old ones would be my first place to start.

If I'm right at least is an easy fix.

Tim M · 17 May 2020, 07:01

I had something very similar after some work to my engine; chap had reconnected the throttle linkage incorrectly so it didn't return to its proper idle position all the time. Sometimes it did, sometimes it didn't. Another cause of this I've encountered is stiff/worn throttle cables which don't quite take the engine back to idle all the time.

alt · 17 May 2020, 18:09

^^ We may have a winner! I think 'worn / stuff throttle cable' could be the reason.

I say this, because I have just remembered that when I have this issue, as i'm bringing the throttle back (say from wide open), moving between idle position and neutral, it's VERY stuff and takes quite a lot of force to return to neutral (much harder than going into gear, as an example)