vibration in a brand new 20 HP Tohatsu

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swump

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I took a brand new Tohatsu 20, 4 stroke electric start for a shakedown cruise today on my 2001 Lowe 1648 MV. The Engine was shipped to me from TN; arrived on time, no damage, no sweat.

She cranked right up, but I noticed immediately that the engine seemed a little noisier than the very quiet 4 strokes I've used. Most troublesome is that the engine vibration seems excessive. Engine vibration is quite noticeable at idle way up in the bow of the boat. It's way more vibration than the 1981 evinriude 15 I ran for a while or the 1984 18 hp merc that preceded it. Vibration is bad in gear or at idle.

The motor starts and runs fine. After 2 hours of break in I ran open throttle for just a minute, got 23 MPH. But at speed there's vibration as well.

Any experience with a magic fingers engine? The dealer did not do the "Pre-Delivery Inspection" that Tohatsu says they should do in their literature. Is taht typical for an on-line dealer?

Thanks for the advice. Time to call the dealer and see what's up.
Swump
 
I would take it to a dealer. Sounds excessive.

Did you check the engine oil and lower unit oil? a Lot of motors are shipped without oil to get around Haz-mat regulations.
 
These ship with lube in the lower unit; it's sealed. I added a quart of engine oil.

It vibrates at idle so I don't think it's lower unit.

I've seen on other forums that the single cylinder 4 strokes vibrate, but not a lot on the 2 cylinder. The guy at on-line dealership says complaints about vibration are very rare in 2 cylinder engines.

I think I'll call a local dealer for service on this thing.

Anyone else run a late model nissan or tohatsu 2 cylinder that can describe vibration or lack of?
 
I own one of those 4 stroke single cylinder 6hp Tohatsu's and it shakes, rattles and roles due to the one cylinder. I hate it actually and am selling it this summer because of the vibration it makes. The 2 cylinder should not behave that way though, the other cylinder should counteract the other and be smooth. I would take it to a dealer immediately as this does not sound right for a brand new 2 cylinder motor.
 
I run a 2008 Nissan 18hp fourstroke and she's runs very quite and smooth. No vibrations at all from day one to year four. I followed the breaking procedures to a T. Best bet is to take it to a dealer if you've followed all the breakin procedures and have the correct lube and oil levels and have the engine mounted tightly on the transom.
 
Have run one of those quite a bit.

They vibrate. Twin cylinder parallel engine-they vibrate unless they're counterbalanced VERY well, which the tohatsu 20 is not. The one I've run is also quite a bit noisier than any of the 20 HP Yamaha motors I've run. I actually have a couple videos comparing them, I may host them at Photobucket later when I've got more time.

P.D.I. is not done by the online seller...this is why I absolutely discourage folks from buying new outboards online. You get what you bought, if it's got a problem, it's a trip to the dealership to (hopefully) have it repaired under warranty. Or the other option, contact the seller and they may want you to ship it back...and shipping these things is not cheap.

If it was purchased at the dealer and there "was" any problem during the PDI process (which is rare but it does happen), they'd either assemble/prep another motor or they'd fix that one and you'd never know about it. Also the P.D.I. would have been done, which proves that they have run it in a test tank, checked for leaks, checked the water, fuel, and oil pumps, propeller nut torque, and a host of other things they check. Now you have to go back to the closest dealer and have them perform the PDI. Some dealers charge for it if you bought it online so be prepared for that. When the motor is invoiced to the dealer, a certain allowance is given to that dealer for setup & prep. Since your selling "dealer" (online) didn't do anyt of that, he pocketed that money. And when you go to another dealer, which did not sell you that motor, they have the right to charge you the labor for the PDI processing. And lastly, the PDI is required by some manufacturers before the warranty can be registered. I know for certain Yamaha does this, but I am not positive about Tohatsu. Yamaha won't even allow warranty registration to be completed unless the PDI form is filled out in it's entirety. It's designed to protect the consumer...even though it's a little more paperwork for the dealer. On the Yamaha stuff, if the PDI is not done, the warranty is not registered...and basically you have no warranty until it's done.

Good luck.
 
T-Todd,
Thanks for the info. I sent you a PM before I read this. You answered the questions I sent.

I found a service provider that seems to be very helpful. He's going to check with the factory Monday.

I'd like to see the Yamaha/Tohatsu video when you get a chance.
 
Hi there,

I have a 2011 15hp Mercury fourstroke and the motor was running rough at idle straight from the dealer. They told me that sometimes the motors will run rough until everything is broken in. I was also told that if things do not clear up bring the motor back in. The motor idles a little rough but once in gear runs great. The water here in the Northeast is pretty cold right now and the temps have been in the 40's. Not sure how marine engines handle the cold as this is my very first (Extreme Newbie). Going to pull and check the plugs tommorow.

G3 1442 Jon boat
15hp Mercury Manual Fourstroke
 
I took it to a authorized service guy that sells boat packages. First lesson is that any Tohatsu service provider will do pre-delivery check on any internet purchased engine at no charge. The guy did that for me and fixed a the reverse engine lock that wasn't quite catching.

No luck with vibration after some carb tweaking by the mechanic. I'm finding that the this engine is dinged for vibration in a number of reviews (see Cabela's reviews of the Nissan for example). It appears that the Yamaha and Honda's are smoother, but of course there's the $600-1000 price difference. There are occasional complaints about other 4 strokes too.

So I can live with magic fingers as long as the engine is reliable. IT seems powerful enough and well made otherwise.

Thanks for the suggestions and info.
 
Well, that is a shame. Seems a strange design.

Since it sounds like you are going to keep it anyhow...any chance that your mounting system could be modified to lessen the transfer of vibration onto the boat? The motor will still vibrate.

Perhaps you can clamp a thicker board onto your transom or something. Might be some ideas on the 'net from others in the same situation. regards, Rich
 
Spent three days on the river with the new engine. I've been through 4 or so gallons of fuel and have almost finished 10 hour break-in. The engine has gotten significantly smoother since as I've gotten deeper into break-in. Engine starts and runs great and vibration has decreased considerably. I would consider that this could be placebo effect (break-in sugar pill) but my fishing partner noticed the change on the third day after taking the middle day off.

The engine runs and starts like it should. Electric start is really nice. GPS says we get 20 MPH with 430 lbs of paunchy middle aged guys and a full load of gear and equipment. 23 MPH with half the old guy load.

This was also the first extended fishing trip in the 1648 Lowe MV since I rigged her up from a bare hull. I am digging this boat.
 

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Nice to hear that she's smoothed out. I'm with you on the electric start, nothing like hitting a button and you're off to the next fishing hole.
 
Nice set up. I dont see a bigfoot switch on the bow deck though. If you dont have one it'll be the best 15 bucks you ever spent!
 
My 2021 Tohatsu 20 hp shakes like crazy when I get to 3/4 throttle. Idle is so quite, trolling very quite. 3/4 throttle and it feels like a concrete vibrator is in the bottom of the boat, everything shakes. I rubber matted the floor so the tackle box, anchor and anything else loose won’t make so much noise. No sneaking up on fish with this motor. It just now has 10 hours on it.
 
I have a 2018 20hp Tahatsu. I am thinking you have a bent prop or propshaft? Something isnt right? Mine has some vibration but nothing like that.
 

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