2006 F40LTR carb problems

[Blackhawk36]

I have read all of the threads on the f40 carb issues. My symptoms are little different.

Problem was caused by water getting in the fuel and sitting in the carbs.

After cleaning the carbs, the engine starts and idles perfectly. The accelerator pumps work as well. I get a nice squirt of fuel into each carb throat when the throttle is moved.

Any time I try to come off if idle, the engine stalls. No matter how much I try to goose it. I have the original jets and they appear clean.

I can move around at idle or slightly above all day long with no problems. I am considering replacing the low speed jet and the main jet with the larger 25hp jets. Am I on the right track. New jets are expensive. About $170 for all six of them.

Thanks

[boscoe99]

Start with the larger idle jet only.

You can get them for a lot less from jetsrus.com

[Blackhawk36]

Boscoe, I was on their website but I couldn't figure out which ones were correct. Can you help.

[TownsendsFJR1300]

How long have you had this engine and did it work fine before???

Point being, If, for years it ran fine, if it IS indeed fully cleaned, it should NOT need a jet change. Especially when you can see fuel
being squirted when moving the throttle..

Sounds like your carbs are still dirty.

Did you pull ALL the jets out (especially the main) and check to see if you can see light thru them? A spritz of carb cleaner W/O pulling them does NOT count..

[Blackhawk36]

This is a 2006 motor. It has run flawlessly til this year. It belongs to my uncle and it gets a lot of use. It is on a Carolina skiff and it is used for crabbing and fishing. Somehow over the winter a lot of water got into the gas tank. The contaminated fuel sat in the carbs for some period of time, possibly months.

I have been able to see light through all of the jets since the first disassemble. The first problem was clearing the accelerator pump jet in the carb throat and the the passages in the bowl that fill the accelerator pump chamber. I was able to do that with the ultrasonic cleaner. Still wouldn't accelerate without stalling.

I did a complete disassembly and cleaning in heated solution again last night. Boat runs great today. If it runs great again tomorrow I am going to declare success. If there is any degradation in performance I will replace the low speed jets.

Thank you.

[TownsendsFJR1300]

I did a complete disassembly and cleaning in heated solution again last night. Boat runs great today. If it runs great again tomorrow I am going to declare success. If there is any degradation in performance I will replace the low speed jets.

Thank you.

Please post back how it goes.

[cpostis]

Please post back how it goes.

Just curious, does the kit in the attachment contain the jets you are questioning? Looks like the kit is for all three carbs? Not bad for the price?

6H4-W0093-03-00 YAMAHA CARB REPAIR KIT

[Blackhawk36]

That is a kit for all three carbs but mine is an F40. The carbs are different. The floats in the picture are different and so are the gaskets. That is a great price though and it looks like jets might be in that bag.

The ones I need are below


JET (#35)
67C-14948-01-00

$22.82




JET, MAIN (#95)
67C-14943-25-00

$27

[TownsendsFJR1300]

Just a side note, I pulled apart an aluminum (non Marine Carb) that was corroded up REALLY BAD several years ago.

The inside was nothing BUT white aluminum corrosion (completely full).

I did get it cleaned out (by hand and got it running), but point being, a small piece of that corroded aluminum/crap could have stayed stuck in your carb body and you got it out the second time around...

[cpostis]

That is a kit for all three carbs but mine is an F40. The carbs are different. The floats in the picture are different and so are the gaskets. That is a great price though and it looks like jets might be in that bag.

The ones I need are below


JET (#35)
67C-14948-01-00

$22.82




JET, MAIN (#95)
67C-14943-25-00

$27

Sorry, I confused you with another thread.

[Blackhawk36]

Just a side note, I pulled apart an aluminum (non Marine Carb) that was corroded up REALLY BAD several years ago.

The inside was nothing BUT white aluminum corrosion (completely full).

I did get it cleaned out (by hand and got it running), but point being, a small piece of that corroded aluminum/crap could have stayed stuck in your carb body and you got it out the second time around...

Yeah, I think that you are correct. That is probably exactly what happened.

[TownsendsFJR1300]

And lastly, Yamaha's "RingFree" fuel additive besides cleaning the combustion chamber also cleans the entire fuel system, HIGHLY RECOMMENDED.

I run it in every gas machine I own, it does keep the varnish out. It is NOT a fuel stabilizer which IMO, should be used even if the engine is run dry(or drain the float bowls when done)-PIA


https://www.shopyamaha.com/product/d...?b=Search&d=34

[Blackhawk36]

Thanks. Just ordered a quart on Amazon.

[robert graham]

How long have you had this engine and did it work fine before???

Point being, If, for years it ran fine, if it IS indeed fully cleaned, it should NOT need a jet change. Especially when you can see fuel
being squirted when moving the throttle..

Sounds like your carbs are still dirty.

Did you pull ALL the jets out (especially the main) and check to see if you can see light thru them? A spritz of carb cleaner W/O pulling them does NOT count..

My 2nd on this!....

[pstephens46]

And lastly, Yamaha's "RingFree" fuel additive besides cleaning the combustion chamber also cleans the entire fuel system, HIGHLY RECOMMENDED.

I run it in every gas machine I own, it does keep the varnish out. It is NOT a fuel stabilizer which IMO, should be used even if the engine is run dry(or drain the float bowls when done)-PIA


https://www.shopyamaha.com/product/d...?b=Search&d=34

I have Ring Free plus fuel additive. Is this not a stabilizer? There was an original "Ring Free". Is there a difference?