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New Tohatsu 4-stroke hard to start

newtoh12

New member
I have a brand new 9.8 4-stroke Tohatsu that is extremely hard to start. First time took over 30 minutes of pulling, checking fuel, oil, plugs, kill switch, & repulling. (New motor has new gas, new oil, new plugs) Finally got it to run, did the 10 minute idling for new engine break-in. Tried again today, and it would not start, did not even try to fire. Finally after much pulling, checking all things again, got it started by advancing throttle past the start and restart lines and up to about a quarter-throttle level. It still took about 6-8 pulls with that.
Experience with other new motors is that they should start easily with one or two pulls.
Contacted 5 dealers in my area and all have 2-4 week backlog, so looking for ideas before taking to a dealer. Anyone have any ideas of a simple adjustment that won't void the warranty?
 
Could be almost anything. Probably your starting technique. All 4-strokes start better with a little throttle, especially when warm. Did your dealer do a PDI on the motor? What do the plugs look like? Sounds like you are too rich, and adding air helps to get around that. Are you choking when the conditions don't need it? Did it reatart OK after warming up? When it ran, what was the idle speed, and how did it operate?

Break-in is 10 HOURS, not minutes. And not at idle.
 
This is my first 4-stroke with a manual start, so may just be a learning curve with it. Dealer did not do PDI, stated not required for under 25HP. Plugs are clean & dry. Using choke initially with cold engine. Idle speed was a bit slow. Since initial post, I've been able to start on first pull as long as I give it more throttle. Appears the throttle needs slight adjustment. This motor needs more throttle when cold.
According to instructions received with this motor, first 10 minutes of break-in time should be idle only. Next two hours less than 1/2 throttle, then increase throttle at varying points for that first 10 hours.
 
Sounds like you have it solved. Not a big problem... mostly technique. But... that is why our shop always does a PDI on every motor, no matter how small, even though it isn't "required" by the factory. The cold idle for any 8/9.8 will be a little slow, and will increase as the oil-heated intake warms up (improving fuel atomization at warmer temperatures)... One reason that we tank test all motors is to verify the idle rpm with a shop tach. The 9.8A3 low-speed operation is particularly lean (thanks to the EPA), and if the warm idle is below 900, it may not cold idle well. You could snug the idle stop screw about 1/8 turn or so. If you have access to a good shop tach, the trolling idle (in gear) should be about 900-950, after the motor has warmed up at least 10-15 minutes. Don't get too carried away with adjusting the idle until after break-in and that first oil change (at 10 hours); the idle may increase a little as the rings seat better towards the end of break-in.

Sorry I originally misunderstood your break-in time. Yes, keep the speeds slow at first, and then increase as per the manual.
 
I've experienced this same issue from time to time. My suggestions for solving it: First, follow the starting instructions exactly, to the T. These engines are very easy to flood, especially in warm weather and if it hasn't been run in a couple weeks. If you do flood it, try these suggestions which have worked for me: 1. Open the throttle all the way, and close the choke. pull until it starts. This allows more air into the system and clears excess gas. This is how we used to start a flooded car back when they still used carburetors. 2. Try disconnecting the fuel line, and pulls it to clear any excess gas in the system. It will probably fire and then die from lack of fuel. Start over with the normal starting procedure and it may just decide to run well.
 
You do realize this is 7 years old... No, don't close the choke to clear flooding. That will make it flood more.
 
You do realize this is 7 years old... No, don't close the choke to clear flooding. That will make it flood more.

OK, yes, my bad. Push the choke in...open it up, let the air flow through. These things seem to be very sensitive to flooding. Pay close attention to starting instructions or you'll get blisters from tugging the cord...
 
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