2013 new 4HP Tohatsu noise

[skipper123]

Just bought a new 2013 4HP Tohatsu yesterday and put it in the water for the break in time. After two hours running it was time for a one min full throttle run. Engine started making a squelling sound almost like a high pitch air noise after I had run at full throttle for one min. I checked the fuel valve to make sure it was all the way open and the vent on the fuel tank on top of the motor was all the way open. When I went back to idle I did notice the oil lite flicker twice and then went back off. Loaded it on the trailer and checked oil again and it was in between the dipstick marks. Kinda made me wonder what the heck was going on and was wondering if anyone else has had the same noise from these engines. Maybe its something with just breaking in a brand new engine ? It had a good stream of water from the pee pipe the whole time running. The squelling sound was pretty loud but changed with throttle position.

 

[colbyt]

Re: 2013 new 4HP Tohatsu noise

I can't imagine running one for 2 hours in a tank. I believe the break in specifies at various throttle speeds not to exceed. I gave mine 10 minutes in the tank and continued the break in on the boat. I think you should call the dealer before running it again.

 

[skipper123]

Re: 2013 new 4HP Tohatsu noise

Never put this in a tank it hit the creek from the start. Followed break in procedures as per owners man. Have run it 2 1/2 hrs so far. I will have to say it runss very nice for a single cyl engine. Dropping from full throttle to idle may have made the oil lite flicker, not sure, It went right back off. Planning to put it back in the creek today and see if sound continues while I continue the break in procedures. I think I have heard a starter rope assembly make a squelling sound before and was wondering about that.

 

[MattFL]

Re: 2013 new 4HP Tohatsu noise

From reading unrelated threads about these motors, I believe there is a bushing in the leg to support the main shaft that can squeal. Not that it's supposed to, just this might be what's squealing.

 

[TOHATSU GURU]

Re: 2013 new 4HP Tohatsu noise

Run it by a dealer and have it checked.

 

[pvanv]

Re: 2013 new 4HP Tohatsu noise

Run it by a dealer and have it checked.

Yep. Can't hurt. That's why there's warranty coverage.

The sound may (or may not) have been the recoil starter partially engaging. Did the sound clear up?

If the motor was trimmed radically, it's possible to slightly starve the oil pump briefly either when throttling up or cutting the throttle suddenly, especially if the oil is a little on the low side. You want the motor straight up and down when checking oil level, and when the boat is running at speed.

What oil are you running?

 

[colbyt]

Re: 2013 new 4HP Tohatsu noise

Never put this in a tank it hit the creek from the start. Followed break in procedures as per owners man. Have run it 2 1/2 hrs so far.

Great.

I don't have the 4. I bought the 3.5 and have finally manged to log about 6 hours with zero unusual noises. The trim aspect as mentioned by others is very important with any 4 stroke.

I would monitor the situation closely. Have you at least called a dealer for info?

 

[skipper123]

Re: 2013 new 4HP Tohatsu noise

Put it in the creek again yesterday and noise was not as loud and only heard it after running full throttle for one min. Im only 3.5 hrs into the break in period as of now. Got rained out yesterday and could only run it for a hour. Taking it to a dealer at this point I feel is a waist of time. Water pump is working and oil level is at top mark on the dip stick screwed in. Im running four cycle engine oil 10w30 I did notice the oil light flicker again after running full throttle and dropping back to idle speed about twice. Anything above idle and the oil light never flickers and it has not blinked or stayed on any while running. This engine does idle very slow but does not cut off. I love the way it idles and will be great for trolling for striper and bass. If it made the noise all the time I would take it to a dealer. I have learned over the years the less time you spend at the dealer and the more you do yourself the better. Nobody will care about your engine like you do. Both days I went out it was raining or about to rain with high humidity. I was wondering if the humid air may make a sound in the intake of the engine.

 

[skipper123]

Re: 2013 new 4HP Tohatsu noise

On a side note this little engine is very smooth for a single cyl engine and pushes my 1542LW Tracker jon boat very well. I would have thought a vacume leak but this little engine idles like a little sewing machine. Its hard to tell is its a squeel or a high pitch air noise. Its a intermittent sound that stops as slow speed. Have not been able to run but one minute at full throttle yet because of break in procedures.

 

[skipper123]

Re: 2013 new 4HP Tohatsu noise

Update, the sound has got quiter as Im now thru the break in period. Everything still working fine but still have the oil light flicker when I run full throttle for a few minutes and drop back to idle. Anything off idle and no oil light so I know the oil pump is working. She is still peeing strong and runs like a gem. Still running off the small fuel tank on the engine at this time but a 3 gal tank is on the wish list. I changed oil to a different 10w30 brand with the same SM SL rating owners man called for but to no avail. She still has a slight squelling noise about 1/4 to 1/2 throttle. Oil is at full mark and exactly 15oz as per owners man dipstick screwed in for checking. If I could get it to make the sound all the time I would have the dealer listen to it but running it in a test tank makes no noise. Seems to be only under a load. Will try and post the outcome after this weekend.

 

[MattFL]

Re: 2013 new 4HP Tohatsu noise

Check your manual to see if it calls for 40 weight oil. My 6hp does and I believe they share the same internals. Thinner oil will lower oil pressure and maybe at idle it gets low enough with 30w to trip the oil light. Just a guess. That or maybe your idle is too low. ; )

 

[pvanv]

Re: 2013 new 4HP Tohatsu noise

All Tohatsu 4-strokes call for either 10w-30 or -40. It needs to be FC-w rated, for corrosion protection. In Northern climates, we prefer -30; in southern Florida, -40 would be appropriate. When new, it's best to be at 1/2 to 3/4 on the dipstick, as the motor will make oil, and you never want to go above full -- not even a drop. The oil light should not be coming on. I would have the dealer test the actual pressure with a real gauge... the sender may be weak, or there may be a real problem.