1992 5 HP Tohatsu won't start

[Maple Ridge]

5 HP Tohatsu was starting but would only run for 5-10 mins and then cut out...wouldn't restart after this.

Fuel ratio fine...new fuel with seafoam added for carb
New Spark plug (properly gapped) and firing fine
New Spark lead-tested too and fine
Dismantled, cleaned and replaced gaskets on carb..looks good
Changed impeller
Took LU apart and looks fine
New LU oil...didn't touch/replace any seals

Still doesn't want to start and seems to be leaking fuel out of what my manual 'says' is the water cooling port???
Also, when you choke it to start, fuel comes out of a hole on the right hand top side of the carb...maybe this is supposed to happen?

Any help would be greatly appreciated!

 

[Sea Rider]

Re: 1992 5 HP Tohatsu won't start

Welcome to the forums,

If you have fuel spills on carb, you have float or needle valve issues...being a 10 year oldie, better buy a new carb kit. Is your fuel pump in good condition, check diaphragms for cracks, balloned, severely dried out, replace if meets that conditions.

Happy Boating

 

[pvanv]

Re: 1992 5 HP Tohatsu won't start

5 HP Tohatsu was starting but would only run for 5-10 mins and then cut out...wouldn't restart after this.

Fuel ratio fine...new fuel with seafoam added for carb
New Spark plug (properly gapped) and firing fine
New Spark lead-tested too and fine
Dismantled, cleaned and replaced gaskets on carb..looks good
Changed impeller
Took LU apart and looks fine
New LU oil...didn't touch/replace any seals

Still doesn't want to start and seems to be leaking fuel out of what my manual 'says' is the water cooling port???
Also, when you choke it to start, fuel comes out of a hole on the right hand top side of the carb...maybe this is supposed to happen?

Any help would be greatly appreciated!

Please describe the "water cooling port". Is this an M5B? If so, the fuel pump is integral with the carb. Did you check the float height? What method did you use to clean the carb? Does the plug get wet when trying to start? It sounds like the carb is severely flooding.

 

[Maple Ridge]

Re: 1992 5 HP Tohatsu won't start

Many thanks. I will check the fuel pump for leaks etc. I Manually soaked and scrubbed the carb and replaced all gaskets. Seeing as I don't have a repair manual, I couldn't 'officially' check the float height, but needle and idle screws were in good shape and nothing glaringly obvious here. Will get back in a perhaps order a new carb kit.

Thanks to everyone who replied-great advise and I really appreciate it.

5 HP Tohatsu was starting but would only run for 5-10 mins and then cut out...wouldn't restart after this.

Fuel ratio fine...new fuel with seafoam added for carb
New Spark plug (properly gapped) and firing fine
New Spark lead-tested too and fine
Dismantled, cleaned and replaced gaskets on carb..looks good
Changed impeller
Took LU apart and looks fine
New LU oil...didn't touch/replace any seals

Still doesn't want to start and seems to be leaking fuel out of what my manual 'says' is the water cooling port???
Also, when you choke it to start, fuel comes out of a hole on the right hand top side of the carb...maybe this is supposed to happen?

Any help would be greatly appreciated!

 

[Maple Ridge]

Re: 1992 5 HP Tohatsu won't start

Welcome to the forums,

If you have fuel spills on carb, you have float or needle valve issues...being a 10 year oldie, better buy a new carb kit. Is your fuel pump in good condition, check diaphragms for cracks, balloned, severely dried out, replace if meets that conditions.

Happy Boating

Thank you. I will get back into the carb and recheck it. THe needle was in good condition but I couldn't do any official float valve height checking because I don't have the service manual for it which is half the problem. I will check the fuel pump because I haven't done this yet...might be a good place to start again.

 

[Maple Ridge]

Re: 1992 5 HP Tohatsu won't start

Please describe the "water cooling port". Is this an M5B? If so, the fuel pump is integral with the carb. Did you check the float height? What method did you use to clean the carb? Does the plug get wet when trying to start? It sounds like the carb is severely flooding.

Well it is one the F/R/Neutral Gear changing side of the motor...toward the back just internal to 2 ports with rubber caps on them. It is a very small peice of rubber that extends down about 1 inch from the motor housing. It has a very narrow opening and will move up and down slightly if you push/pull it. From the motoe side you cannot see where it comes from.

Yes, this is an M5B. So then the fuel pump is integral with the carb? So the good news is I don't have to check the fuel pump? What height should the float be set at? I believe I did a pretty good job cleaning the carb but do you have any further reccommendations? I used a toothbrush, seafoam, carb cleaner, rag, and compressor to blow out the holes. What do you think?

Thanks for your help.

 

[pvanv]

Re: 1992 5 HP Tohatsu won't start

Well it is one the F/R/Neutral Gear changing side of the motor...toward the back just internal to 2 ports with rubber caps on them. It is a very small peice of rubber that extends down about 1 inch from the motor housing. It has a very narrow opening and will move up and down slightly if you push/pull it. From the motoe side you cannot see where it comes from.

Yes, this is an M5B. So then the fuel pump is integral with the carb? So the good news is I don't have to check the fuel pump? What height should the float be set at? I believe I did a pretty good job cleaning the carb but do you have any further reccommendations? I used a toothbrush, seafoam, carb cleaner, rag, and compressor to blow out the holes. What do you think?

Thanks for your help.

You may be describing the telltale. But not sure from your description. Grab a Factory service manual (from any dealer, including me) so you can refer to it as a guide. The float height is correct when the float is parallel to the casting when the carb body is held inverted. You did not do a thorough carb cleaning. That requires a complete disassembly (including jets and the emulsion tube nozzle), followed by a 4-hour soak in real carb dip, then a liberal spray-out with aerosol carb spray. Then you can reassemble it and verify float height.

 

[Sea Rider]

Re: 1992 5 HP Tohatsu won't start

Have you inverted the float position when re assembling back carb ? Probably that could be the trouble cause ? So needle tip is completely round and inmaculate and you have checked internal fuel pump diaphragms condition , right ?

Happy Boating

 

[Maple Ridge]

Re: 1992 5 HP Tohatsu won't start

Many thanks to all who offered their advice. I restripped the carb completely, resoaked it (AGAIN) and reassembled with a new float and needle, gaskets etc.

Then did the same with the fuel pump....diaphragms looked ok, but in hindsight, I think they were probably the problem. Replaced everything and reassembled.

The telltales were leaking out gas/oil mix with the other problems, BUT now are fine.

Pulled the cord and started on the first pull.

Ran it for 15 minutes to make sure it wasn't going to stop on me.Perfect!

Will put it in the water now to make sure it works properly.

Thanks so much everyone for your help! This is a great forum for rookies like me!
Now I just have to convince my husband that this wasn't all luck!
Will be sailing this afternoon if all goes well.

5 HP Tohatsu was starting but would only run for 5-10 mins and then cut out...wouldn't restart after this.

Fuel ratio fine...new fuel with seafoam added for carb
New Spark plug (properly gapped) and firing fine
New Spark lead-tested too and fine
Dismantled, cleaned and replaced gaskets on carb..looks good
Changed impeller
Took LU apart and looks fine
New LU oil...didn't touch/replace any seals

Still doesn't want to start and seems to be leaking fuel out of what my manual 'says' is the water cooling port???
Also, when you choke it to start, fuel comes out of a hole on the right hand top side of the carb...maybe this is supposed to happen?

Any help would be greatly appreciated!