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Problems starting my 9.8 4stroke Tohatsu

N

NGT

New member
Here's what's going on:

-Running it in my driveway: It takes 5-6 pulls to start and might stall out once. Then it runs fine in the driveway. I never put it in gear at home, but once going, it will idle just fine for as long as I want.

-Running it in the water: Takes 6-8 pulls to start and stalls out a few times. Usually I have to shift it into gear with a tiny bit of throttle turned which causes a jerk on take off, to get it to go without stalling out. This is still after warming it up for 5 minutes or so. Once I get going, I can idle/troll all day long fine. If I turn it off to stop and fish, and only stay in a spot for 1-2 hours, it usually starts right back up fine. If I'm stopped all day, I usually have to pull 3-4 times and it might stall once before it's idling fine and I can take off again.

-Where I fish: I only run it in salt/brackish water. Mostly in the Napa River or Petaluma River. I run it in the garbage can of fresh water for 5-10 minutes in my driveway everytime I come home. I was told that I should unplug the gas hose from the motor and let it run until it dies. I have never done this.

-Other thoughts: I am new to boats and motors in general and may just be starting it wrong. If I open the valve on the gas tank all of the way open and pump the bulb, it feels like barely any fuel is going through and I'm just pumping through air. If I only open it a little bit, it pumps through gas just fine. It's a this tube. How many times should I be pumping the bulb if I only open the valve a little bit? If I'm opening it all of the way and it feels like I'm pumping through 90% air, is there a leak? Possibly just needing to replace the gas hose?

I usually pull the choke out all of the way and once it starts, I push it back in. Am I doing this wrong? Should I push it in slowly? I've been told to "use the choke" but I'm not sure what that means.

I ran these same details past the folks over at iBoats and they were leaning towards needing to clean my carb. I ran this by a local mechanic and he said:

SOUNDS LIKE YOU NEED TO USE THE CHOKE AND NOT SO MUCH GAS IF YOU CAN LOOK UP A MANUAL AND OR SEARCH FOR A DAHATSU FORUM ONLINE YOUR PROBLEM WILL BE SOLVED. IF YOUR FUEL LINE PRIMER BUBLE GETS SOFT AT ANYTIME YOU HAVE A AIR LEEK IN THE LINE THAT MIGHT BE GIVING A FAULTY START
Click to expand...

I don't really have much money, wife out of work and a baby on the way, but I'd love to get out on the water before he comes in February, while I still have time. Any help would be appreciated!!

thanks!

-E
 
You should always run fuel out of the carburetor when done ,--------this keeps the carburetor clean and prevents the stalling you are experiencing !!-------------I suggest taking the carburetor apart for a good cleaning.
 
Yep, classic varnished carb symptoms. Just a little too lean, especially at slow speeds. Higher loads (such as coming off idle under load, require a richer mix. Thorough and proper cleaning requires complete carb disassembly (including jets and emulsion tube "nozzle"), and a 4-hour soak in carb dip, followed by a blow-out with carb spray. Then a careful reassembly, paying close attention to the float height. Always disconnect the fuel line at the end of the day, and let the motor run the carb out, and this will help prevent future varnishing.

As for the primer bulb, what valve are you talking about? The vent should be open when running.
 
Will something like Sta-bil help fix the problem? I bought some a while back but never tried it out. Or is this stuff just made to prevent this from happening before it gets to this point?

I don't have $400 to take it into a shop and get the carb and jets cleaned up. How hard of a job is this? I've never done any real motor work on anything, besides checking the oil and changing some spark plugs. How long should this take a shop as far as work hours. The only local shop that works on these wants $96 per hour and said it would take the first hour to assess the problem.

Either way, thanks for the advice. It's much appreciated!

Edit: As for the valve thing, yeah, the vent on the gas tank. When I open it all of the way up and pump the bulb, it feels like I'm pumping through 90% air and very little gas. I could pump it 5-7 times without it getting hard. Is this normal? With the valve all of the way open, how many times should I pump the bulb before starting the motor?
 
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There is no such thing as an effective mechanic in a bottle. Fuel stabilizers only help slow down fuel spoiling/rotting; better to never run fuel older than 30 days in any atmospherically-vented system. Stabilizers do nothing to prevent varnishing that occurs when fuel evaporates. There is a remote possibility that a super-dose (maybe 10X the recommended dosage) of a fuel injector cleaner, such as Chevron Techron may help, if run for several hours/days, but we have had mixed results with that technique at best.

Removing and installing the carb requires only basic mechanical skill, and a decent set of metric tools, including a long ratchet extension for the inner carb mounting bolt. Disassembly of the carb requires a little more dexterity and care, but can be done by anyone who is armed with the proper exploded parts diagram (preferably a Factory service manual, Part # 003-21056-1, $27.58), a very clean bench area, good, stout screwdrivers that fit the jets perfectly (so the jets and nozzles don't get mangled), and average mechanical skills.

Then all the hard parts go into a basket and are submerged in carb dip, such as Tyme (available in 1-gallon cans at auto parts houses), for 4 hours at room temperature. After the bath, each individual piece is blown out with generic carb spary, all passages in the carb body are blown out as well, and the carb is reassembled and reinstalled. In some cases, a new carb kit, Part # 3V1871220M, $34.75, needs to be installed, due to wear or deformities in the soft rubber or plastic parts.

Our shop typically would have an hour or so of labor (our rate is $75.00/hr.) in cleaning and tank testing a 9.8 carb. Diagnosis is another thing entirely, and varies a lot, depending on the skill/experience of the technician, and how obvious the problem is. Your situation sounds like a typical varnished carb, so it shouldn't take too long to diagnose. FWIW, a new carb for the tiller model 9.8A2/A3, 3V2031002M, costs $171.12, and can be purchased from any dealer, including me. Those carbs are presently on national B/O, so it would probably take a few weeks to get one in your hands, unless a dealer happens to have one on the shelf. You can find dealers near you by doing a search at http://www.tohatsu.com/dealersearch/index.html

You may have a leak in an o-ring in a fuel line connector, allowing air to enter the gas hose. That would make for more pumps to get the bulb firm. Likewise, the primer bulb could have a lazy check valve in it. You want the vent open when running, and how far it's open shouldn't affect how many pumps it takes to get the bulb firm. If the carb is completely dry, it can take several squeezes to fill it; The 9.8 carb has a fairly large bowl to fill. Does the bulb eventually get firm? If not, there is a problem -- either air in the system, fuel leaking out at the needle valve at the carb (doubtful in your case), or a bad primer bulb.
 
Thanks for all of the info. Not sure if I have all of the right tools and the last thing I want to do is damage something. There's one shop that's close, but I don't trust him as far as I could throw him. Guenters Outboards ruined my last Honda outboard and "after" I went to him, I have only heard bad things about him. After reading your prices, I'm going to pass on Ace Marine's $400+ price quote. There's another shop about 35 miles away. (Marine Outboard) Looks like I'll be going there as they have a couple of good reviews up online.

As for the vent. When it's only open a couple of turns, maybe it's not even open, and that's why the bulb gets hard. When I open it all of the way and pump the bulb, it's almost like a weezing type pumping sound like you'd hear if you stepped on a rubber ball with a hole in it and a small amount of water inside. When it's all of the way open, I think I could pump it a dozen times before it got hard. I'll pull it out this weekend and see for sure. My last motor had a much thinner fuel hose and 2-3 pumps got it hard every time.

With the super dose of fuel injector you mentioned, as far as the mixed results. Does it ever result in damaging anything, or is it just sometimes it works and sometimes it doesn't. I don't want to mess anything up, but would give it a try if it wouldn't hurt anything.

thanks again for all of the info and help!!
 
Hopefully you locate a reasonably-priced, reputable mechanic dealer nearby. Our shop could do the work, but you would have to pay shipping to and from Buffalo, which adds to the cost, then approaching the cost of a new carb. :(
The vent should not have any effect on the primer at all. Your primer may have a bad check valve, leaking back into the tank when squeezing. Your local dealer can check that for you.
The super-dose of techron may or may not work, takes a lot of time (hours or days), and is not as thorough as a proper cleaning. But some have used it successfully. YMMV.
 
I went into Kregan today to ask about the fuel cleaners and there were 100 different types. Some said "Carb Cleaner" and some said "complete fuel system cleaner". I talked with the guy at the shop and he said it's a bad idea to over dose with anything in an engine to try and clean it out. He didn't really give me any reason, but he said there's a reason for their recommendations. For boats and stuff, I'd go with what people say here over what's said at the part shop, but was wondering if there was a specific name and type? Or just the complete Chevron Techron Fuel System Cleaner? Or go with one that's specifically for Carb Cleaning?

thanks!
 
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