90 HP YAMAHA OUTBOARD very slow in reverse! i this normal?

[TONYG279]

yamaha runs great but goes really slow only in the reverse gear. when given rpms no real change. is this normal? maybe a safety thing?

[TownsendsFJR1300]

No slower than any other engine...

Remember, the prop is the most efficient in forward, NOT reverse...

You should see substantial water movement under the boat, throttled up (it won't move as fast as in FORWARD GEAR).

You may want to mark your prop and prop shaft in that you may have a spun hub..

[TONYG279]

What got me to noticed was that i had to lower the shift lever almost all the way down in order for the boat to move at iddle speed going backwards

[99yam40]

What got me to noticed was that i had to lower the shift lever almost all the way down in order for the boat to move at iddle speed going backwards

pushing the lever that far should have raised the RPM way above idle

[TownsendsFJR1300]

What got me to noticed was that i had to lower the shift lever almost all the way down in order for the boat to move at iddle speed going backwards

^^^, I take it you mean CONTROL LEVER, at the helm?


You should be able to shift into reverse and idle. Pushing back farther on the lever should increase RPM's


Sounds like a cable adjustment (throttle) is needed.

As noted above, the RPM's should have raised considerably, (at least to 2,000 RPM I'm guesstamating).

[DennisG01]

This sounds more like a function of the boat - specifically the transom - than it is of the engine. I say this since you make it sound like you can get plenty of RPM's in reverse.

What boat? Bracket mounted?

Is the prop in PERFECT shape?

Is this your first boat? You do know that boats are designed to go forward, right? GoBeing efficient in reverse is/was NEVER a gleam in the eye of the boat manufacturer.

[TONYG279]

i will find out next time if the RPM increase or not, what i can tell you for sure is it did not scream when RMPs increase and second, the boat did not behaved that way before, i have been with the boat close to a year and it was not like that before, i had to be really careful backing up because of the speed. This only happens going in reverse, forward its perfectly fine.

[TownsendsFJR1300]

i will find out next time if the RPM increase or not, what i can tell you for sure is it did not scream when RMPs increase and second, the boat did not behaved that way before, i have been with the boat close to a year and it was not like that before, i had to be really careful backing up because of the speed. This only happens going in reverse, forward its perfectly fine.

Well, you know something is NOW DIFFERENT...

Besides checking cables, cable adjustments, check linkages (likely NOT your issue)..

Have someone work the helm control (on muffs running), or someone turning the prop(engine off) and watch what the carb throttle/cable does UNDER the cowl.
It should be accelerating with the helm control pushing further back(more throttle).

[TONYG279]

i will check it once the weather allows me, it has been raining like crazy down here in Miami, is the shit lever suppose to move forward or backwards if the engine is off? i tried yesterday with the cowling off to see the linkage move, but i could only move it a little bit forward and a little bit backwards? i am not sure the switch should be open like in a car, or the engine on

[TownsendsFJR1300]

i will check it once the weather allows me, it has been raining like crazy down here in Miami, is the shit lever suppose to move forward or backwards if the engine is off? i tried yesterday with the cowling off to see the linkage move, but i could only move it a little bit forward and a little bit backwards? i am not sure the switch should be open like in a car, or the engine on

Depends on where the lower unit gears are "sitting". That's why I posted move the prop by hand (engine off) or running on muff's- then it'll shift(with the shifter)

DO NOT FORCE THE SHIFTER NOT RUNNING) or you WILL have serious issues...



My F150, on the boat lift (partially in the water), shifting into gear:https://www.flickr.com/photos/147134...6/35586610891/

[fairdeal]

is the shit lever suppose to move forward or backwards if the engine is off?

maybe, but probably not.

'shifting into gear' either the forward or reverse
involves sliding a toothed 'dog clutch'
which has to "mesh" into 'cavities" on the gear

when the motor is not running, the gears are stationary
and unless - by random chance -
the cavity in the gear happens to line up with the tooth on the dog clutch -
they cannot mesh
and you won't be able to move the shift lever

with the engine off,
if someone else rotates the propeller
then the dog clutch turns
and eventually will line up to allow shifting

[fairdeal]

this is a typical outboard gear (forward or reverse) and dog clutch.

You can see the projections on the dog and the recesses areas of the gear.

They have to "line up" to engage.

Them not lining up, is the grinding/clicking noise you hear as you shift

which is why you should shift quickly - get it over with

[TONYG279]

thank you for the lesson, now i understand better, i did not forced it to engage, i just noticed it was hard and did not engage.