1994 Nissan 5hp - dies after few hours of running

[GulfCoastYama]

Hey all I'm hoping to get some help with my 1994 Nissan 5hp tiller. The motor always starts right up cold, even if sitting for a week. My problem is once I'm out on the water running for a few hours, it will suddenly just die. After it dies, it takes a lot just to get it started again. Sometimes ill open full choke, pull once, shut off choke pull again and it will start. Other times ill have to shut off the gas tank switch on the motor (has an internal fuel tank) and go full throttle and pull hard afew times to sputter to a start, just to stall again. The only way I've found to keep it runing after it dies is I keep the gas switch off, just till it sounds like its about to stall. Ill turn the gas on for 3 seconds, then back off for 10 secs, then back on for 3 all the way home. If I just leave the gas switch on the motor just dies, but this is only after its really warm and has stalled. Also I can always tell when its about to have this problem because the motor will start to run like the gas is already switched off, you can hear it running a little faster then al the sudden stall. Any ideas? Thanks for the help

 

[Sea Rider]

Re: 1994 Nissan 5hp - dies after few hours of running

Welcome to the forums,

If it's a 2 stroke engine with internal tank you can't go boating for long hour periods as the tank is quite small, seems a fuel related problem. Remove internal tank from base, pour gas leftovers on a container and clean tank interior, remove valve from tank, has a small linear mesh screen, clean it properly, probably with small stuck debris, if ok, remove carb and clean it properly in carb cleaning solution. That engine comes with a 3 gal external tank and it's fuel connection, is the problem same when using ext tank compared to internal tank use ?

Happy Boating

 

[GulfCoastYama]

Re: 1994 Nissan 5hp - dies after few hours of running

Sea Rider,

I bought the motor used and I only have the internal tank, plus I bring a full 2 gallon can along with me. I tried starting it today and runs fine with the gas switched off, but 3 seconds after I turn the gas on it just stalls and gas leaks from the carb

 

[Sea Rider]

Re: 1994 Nissan 5hp - dies after few hours of running

Check float valve and float condition, probably worn out, seems valve not closing when correct gas level pushes float upwards, that's why the fuel spills through carb. If possible place a new carb kit, will have all needed parts.

Happy Boating

 

[GulfCoastYama]

Re: 1994 Nissan 5hp - dies after few hours of running

Sea Rider

I've had times when it was acting like this one minute, then just stops and is fine. Would this be the float sticking, then just comming unstuck? If that's the case is it a bad part or just being gummed up?

 

[pvanv]

Re: 1994 Nissan 5hp - dies after few hours of running

Yep. Disassemble the carb and clean it all up. May need a carb kit, as the needle may be worn. The needle is not always seating correctly, causing excess fuel to flood the carb.

 

[Sea Rider]

Re: 1994 Nissan 5hp - dies after few hours of running

It's near mission impossible to have a stuck needle when engine is working as there is lots of gas passing through it, needle must be completely round and pointed at upper rubber tip to work properly, if deformed change it, if in opt state, clean well needle seat with a Q-tip dampened in acrylic thiner in round circles. Being an 18 year oldie would suggest to change float chamber o'ring, pump diaphragms and plugs to start like new.

Happy Boating