Tohatsu MFS 20C Shift Lever Rattle

Packard8

Seaman
Joined
Apr 8, 2007
Messages
72
Hi Folks,

Installed a new impeller and test ran the motor in a barrel, runs nice with plenty of water out the tell-tale.

At around 2000 RPM (just guessing, no tach) the shift lever rattles/vibrates like heck against the plastic shift gate cover... a really LOUD buzz. Probably not a major issue, but really annoying. I applied a "Bubba Fix" by wrapping about 1/32" of electrical tape around the lever, which helps but does not totally fix the "buzz".

Am I the only one who has had this issue and applied Cooter & Bubba's "Agro-American Engineering Upgrade"? Or has Tohatsu been made aware of this and retrofitted some sort of rubber sleeve on the lever or gate?

Thanks for any insights,

John
 

pvanv

Admiral
Joined
Apr 20, 2008
Messages
6,567
Re: Tohatsu MFS 20C Shift Lever Rattle

John,

The shift lever may have too much play. It pivots on a sleeve (bushing) and is retained by a bolt and washer. if anything is loose with that attachment, I can see where it could vibrate around.
 

TOHATSU GURU

Admiral
Joined
Jul 22, 2004
Messages
6,164
Re: Tohatsu MFS 20C Shift Lever Rattle

Might be a barrel issue. Not providing enough support for the engine mounts.
 

Packard8

Seaman
Joined
Apr 8, 2007
Messages
72
Re: Tohatsu MFS 20C Shift Lever Rattle

Thanks for the suggestions guys.

I did check the attaching bolt at the base of the lever and it was/is tight.

The rattle persists whether running in the barrel or firmly attached to a stout wooden stand using muffs. Maybe just the nature of the beast, but if present in others of the same model I would expect that it would have been been noted and reported to Tohatsu and a correction applied.

Another question please.... is the telltale output dependent on the position of the thermostat? Sometimes it takes maybe 20-30 seconds for the water stream to appear, primarily when running on the muffs.

Thanks,

John
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Re: Tohatsu MFS 20C Shift Lever Rattle

If muffs doesn't adjusts tight to leg losing water pressure through water intakes sides, or garden hose pressure is not optimum, those are the cause, thermostat sitting position it's not fixed, rotaes 360? on base.

Happy Boating
 

Packard8

Seaman
Joined
Apr 8, 2007
Messages
72
Re: Tohatsu MFS 20C Shift Lever Rattle

If muffs doesn't adjusts tight to leg losing water pressure through water intakes sides, or garden hose pressure is not optimum, those are the cause, thermostat sitting position it's not fixed, rotaes 360? on base.

Happy Boating

Thanks Sea Rider,

By "position" of the thermostat I meant open or closed, rather than the orientation in the housing. On inspection I see there is a small secondary water intake on the underside of AV plate...perhaps that should be taped off to direct all of the water into the primary intake on the leg when using the muffs.

When practical, it seems best to run in the barrel, but when flushing on the trailer at the lake the muffs would seem the only choice.

Cheers,

John
 

TOHATSU GURU

Admiral
Joined
Jul 22, 2004
Messages
6,164
Re: Tohatsu MFS 20C Shift Lever Rattle

The telltale output has nothing to do with the thermostat being opened or closed.
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Re: Tohatsu MFS 20C Shift Lever Rattle

If you are losing too much water sideways of ear muffs or garden hose has poor water pressure, tape with duct tape Cav Plate under water intake to better water amount coming inside water pump, will pee much better. Don't forget to remove tape, you don't want to catch kelp, banana peel and block intakes on your way and fry impeller by runing it dry with assured overheat fatal consequences to the head.

Place muffs on leg, make with epoxy cement 2 retainers at front of leg, will help to retain belt much better on U bar; will achieve having tight muffs on water intakes than before.

Happy Boating
 

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Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Re: Tohatsu MFS 20C Shift Lever Rattle

Great idea Sea Rider,

Thanks!!

Forgot to ask, if you remove cowl while engine is on, does the buzz, strange sound, whatever is heard, while throttling, still persisits ?

Happy Boating
 

Packard8

Seaman
Joined
Apr 8, 2007
Messages
72
Re: Tohatsu MFS 20C Shift Lever Rattle

Forgot to ask, if you remove cowl while engine is on, does the buzz, strange sound, whatever is heard, while throttling, still persisits ?

Happy Boating

Thanks for the note. The rattle is the same with or without the cowl in place. It is the shift lever vibrating laterally in the plastic gate cover with the "F,N & R" markings. I can stop the rattle by holding the lever still with my hand and the wrap of electrical tape I've installed lessens but does not eliminate the noise. If the factory would have installed a rubber cushion on the lever, the sides of the cover or both I think the noise issue would be solved. Guess I'll just live with it or fab a better cushion myself.

Cheers,

John
 
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