Nissan engine bogs down

[bigfish01]

My Nissan 6hp 4 stroke engine (NSF 6A2S) will run fine in neutral at ALL rpm's , but when it is in forward, engine will run only well at low speeds. When I try to accelerate, it bogs down and sometimes stalls. I cleaned carb and fuel filter, but no change in performance. I use chevron highest octane fresh gas. Any help would be appreciated.

 

[Sea Rider]

Re: Nissan engine bogs down

Probably is picking air through the gas hose somewhere ?

Happy Boating

 

[TOHATSU GURU]

Re: Nissan engine bogs down

Cleaning the carb means taking it apart and soaking it in a one gallon pail of carburetor cleaner for three hours, then blowing it out. Anything other than that is considered carburetor polishing.

 

[pvanv]

Re: Nissan engine bogs down

My Nissan 6hp 4 stroke engine (NSF 6A2S) will run fine in neutral at ALL rpm's , but when it is in forward, engine will run only well at low speeds. When I try to accelerate, it bogs down and sometimes stalls. I cleaned carb and fuel filter, but no change in performance. I use chevron highest octane fresh gas. Any help would be appreciated.

Don't ever clean those disposable fuel filters; If fouled, replace it. A thorough carb disassembly and soak in real carb dip, followed by a blow-out, and careful reassembly. checking float height, will probably straighten things out. Thereafter, always, religiously, run the carb dry at the end of each day. 87 octane is plenty; Premium is unnecessary.

 

[bigfish01]

Re: Nissan engine bogs down

Thanks for your responses. What type carb dip do you recommend? A lot of stuff out there that doesn't clean very well. Also will these cleaners damage the reeds or anything in particular.Thanks again

 

[TOHATSU GURU]

Re: Nissan engine bogs down

No reeds in a carb...I always liked Gunk products, but, I suspect they all work about the same. Our last five gallon can came from NAPA, I have no idea what brand it is, but it works just as well... Apparently.

 

[pvanv]

Re: Nissan engine bogs down

Thanks for your responses. What type carb dip do you recommend? A lot of stuff out there that doesn't clean very well. Also will these cleaners damage the reeds or anything in particular.Thanks again

Best dip I've used was Tyme.

 

[marineswarm]

Re: Nissan engine bogs down

I am not sure what year yours is but i have an older late 80's early 90's Nissan, and i have been haveing the same problem, basicly running like crap, when get full throttle runs all right and then falls on its face. Well after taking carbs off to make sure nothign gumed up, it was not. replaced the fuel line and bulb, was dry rotted a little. still same problem. I went to marine shop and got some of that 2-4 fuel conditioner. And i tell you what purred like a kitten, then i started putting higher octane fuel, and one heck of a differance. i think the the gas drawls moisture and the conditinor takes care of that, and higher octane means less moisure drawling. That helped me out so try that sir. and if its like a motor like mine, make sure your oil is being pumped properly, Just today mine quit and scored the piston sleeves, took off the head and dry as a bone, one cylinder has 30 LBS and the others have 120lbs. A very sad day for me.

 

[pvanv]

Re: Nissan engine bogs down

Just like in your earlier post: His motor is nothing like yours, and his problem is not related. OMC conditioner does nothing for water in the fuel. 87 octane is plenty; Higher octane does not affect water absorption. No "mechanic in a can" products will fix this kind of problem.

 

[bigfish01]

Re: Nissan engine bogs down

Thanks again for you help guys. I getting ready to dip it and was wondering do I need to remove brass plug over 1-15 screw, and if so how to do it?

 

[pvanv]

Re: Nissan engine bogs down

You should not need to get in there. That's the idle pilot screw. Technically, it's against federal EPA regulations to change how it's set. But, if you do disturb that setting, it should be put back where it was, or at least adjusted by a seasoned mechanic with a good ear and a precision shop tach.

 

[bigfish01]

Re: Nissan engine bogs down

Thanks for your help guys. Running fine now. One other question. I had ordered a fuel filter and they had sent me the wrong one. The hose will fit on the inlet and outlet, just the filter itself is just bigger than the original. Is it ok to just use the bigger filter. Thanks again.

 

[pvanv]

Re: Nissan engine bogs down

You're probably OK... But I would run the 369022300M FUEL FILTER $11.07, which is the proper filter for all Tohatsu/Nissan single-carbureted 4-strokes. It's really fine (about 10 microns).