Engine Knocking When Put into Gear (Slow Idle)

[SideW@ys]

Hello, I have an 84' Johnson, 100 HP, Model-J100WTLCRS. I have noticed the last two months or so that when I first engage the throttle the engine sometimes "knocks" or "lurches" at slow idle but stops once I give it a little gas. I first noticed it after I had change the gear shift control cable but I'm not sure if it is related. When I put it in gear the lever is where it is supposed to be and I adjusted it even a little more just in case but it is still happening. Only when I increase the throttle from a slow idle it doesn't happen. About more than a couple of miles per hour to give you an idea of just how much throttle. Any suggestions? Is this a lower unit problem or do I possibly I have a cylinder misfiring? Any help would be appreciated. Thank You!

 

[F_R]

Re: Engine Knocking When Put into Gear (Slow Idle)

Hello, I have an 84' Johnson, 100 HP, Model-J100WTLCRS. I have noticed the last two months or so that when I first engage the throttle the engine sometimes "knocks" or "lurches" at slow idle but stops once I give it a little gas. I first noticed it after I had change the gear shift control cable but I'm not sure if it is related. When I put it in gear the lever is where it is supposed to be and I adjusted it even a little more just in case but it is still happening. Only when I increase the throttle from a slow idle it doesn't happen. About more than a couple of miles per hour to give you an idea of just how much throttle. Any suggestions? Is this a lower unit problem or do I possibly I have a cylinder misfiring? Any help would be appreciated. Thank You!

Sounds to me like it might be idleing too slow.

 

[bktheking]

Re: Engine Knocking When Put into Gear (Slow Idle)

Sounds to me like it might be idleing too slow.

Or it could be your gears in the lower knocking until it gets into gear.

 

[SideW@ys]

Re: Engine Knocking When Put into Gear (Slow Idle)

Thanks for the replies. Well it used to idle too slow but it would just die out and not do this knocking thing. So I adjusted the idle and it idles perfectly now in neutral and I never had a problem before putting it into gear. As for the gears in the lower unit, that may be it but I can't be certain. It grinds a little bit getting into gear but after it catches it seems to be fine with the exception of the occasional "knock at low speeds". It has been progressivly getting worse over the last two months.

 

[Fl_Richard]

Re: Engine Knocking When Put into Gear (Slow Idle)

Tiny bit off topic but.....

Boat engines don't grind going into gear. Shifting into gear is not a smooth soft action, it is sudden and deliberate.

There are dogs that engage each other while putting it into gear. Slowly shifting makes these dogs slowly grind together as your not moving the cable enough to allow them to fully engage.

It should clunk into gear, not grind.