Clogged fuel filter?

[bob r]

I believe I have a clogged fuel filter on a 4 h.p., 4 stroke tohatsu, coming back into launch it died at full throttle, started back up,would idle O.K., acted like it was fuel starved when throttle was opened wide again.Original filter, prob. a couple of hundred hours on engine, if anyone is familier with these engines, filter is under fuel tank, 3 visible bolts to remove,are there any more holding tank that I can't see? Are hoses long enough to lift tank and clamp off filter feed from tank? Any input would be appreciated, Thanks , Bob R

 

[lowe1648mt]

fuel filter

The only other things I could think of are
1-vent not open on tank
2-fuel vable not open all the way
3-cloged high speed jet in carb
4-dirt in inlet needle and seat

 

[bob r]

Vent was opened, fuel cutoff petcock was open all the way, I believe it's the filter, was hoping for some insight from someone who has had the fuel tank off on one of these, I'll keep you posted as I'm going to dive into it today.I'm certainly hoping (and strongly believe) that the carb is fine.I've always been religious about fresh clean fuel and it's been trolling slow great and running at speed just fine. Thanks for input.bob r

 

[bob r]

Well, I got the fuel filter replaced, wasn't a problem as the tank hoses had enough play to replace fuel filter pretty easily. Put the engine into a barrel and it fired right up, still must put it on the lake and wind it up to see if I've solved issue. i noticed that the input hose from filter to carb had an amount of dried brown crud around the fitting it goes into, didn't see anything in hose, don't think it was passed on to carb, any idea what may be causing this? Bob R

 

[MackPrince]

Bob,
Did you pull the plugs? I've also had similar issues with old gas, and ethanol issues. Last year I had to take 6 gallons to the transfer station and swear by marine sta-bil or seafoam now with every fill-up. I had similar issues with only being able to run at low idle and it was usually a fouled bottom plug.

-Mack

 

[bob r]

I have not pulled plugs, will do so now, thanks for reply. bob r

 

[bob r]

Only one plug, looked O.K., changed it anyway as over 5 years old and had replacement handy, we'll see when I get it on the water this weekend. Bob R

 

[SilverBullets]

Bob...What year is your Tohatsu? Other than this latest issue how do you like it? I was thinking of getting either the Tohatsu or Nissan 4-6hp.

 

[bob r]

I believe we bought it in 2005, we have had NO issues with it, it has been really reliable, the only issues we had were at Lake Chelan, that was due to altitude issues,if I had readjusted carb for that elevation we would have solved issue, as it was a quick one day outing I didn't bother. We use it on a 15 ft. Old Town flatback canoe that is rated for a 5 h.p., ours is a 4h.p. I would recomend it personally. Bob R

 

[lowe1648mt]

fuel filter

What brand of fuel conditioner did you use? The two years I used sta-bil in my roto tiller I had brown gunk in the tank. this last tme, the plastic was eaten off of the filter. I've never used it in my outboard. There I use the Merc product.
I also had to rebuild the carb on the roto-tiler. It had rust on the parts in- side of the fuel chamber.

 

[Pogue]

Heres another troubleshooting option for you to look into:
http://www.evinrude-parts.com/boat_ethanol_danger_precaution.html

SilverBullets, I cant speak about the smaller Tohatsu outboards, but I bought a new 40HP Tohatsu around 1997 and I love it! I have had no issues with it and if I were in the market for a new outboard, I would definately buy another.

 

[bob r]

Problem solved! After swapping out fuel filter and spark plug took engine to Lane Nawatzul in Mason County to try out the engine (and catch a few fish!)Rain was horrible, never let up, engine ran great at both low troll speed and full throttle. Melanie and I took 4 nice holdover trout between 12 and `15 inches, a nice bonus to an engine test. Thanks to all who gave advice, I'm starting a new thread about fuel additives and what people have used sucessfully. Bob R