Tohatsu High Altitude Jet Kits for the MFS15C

[5thwheeler]

I'm running my MFS15C at 6k ft. and I need to know which high altitude jet kit I should use, and is there a video that shows how to swap out the jets?

 

[pvanv]

Re: Tohatsu High Altitude Jet Kits for the MFS15C

Unless you are fouling plugs, you would run the stock jets. If you are drowning the plugs in gas, then you would get the 3BH102300M HIGH ALT. ADJ. KIT, MFS15C (~9840 FT.) $40.13. The kit will make the motor too lean at sea level, so if you change altitudes, you will need to either change jets, or have a spare carb (one for low altitudes, and another with the high altitude jets). To install the kit, you remove the carb, disassemble as usual, and install the leaner jet kit. You can see the location of bits in the parts catalog, or grab a Factory service manual, available from any dealer, including me.

 

[Sea Rider]

Re: Tohatsu High Altitude Jet Kits for the MFS15C

Paul, if you have installed a max altitude kit for 9000 feet and wanting to take that same engine to 13,500 feet, would leaving the 9K kit experiment same performance as in 9 K altitude or slight less ? Are there lot's of leaner size jets to play with ?

Happy Boating

 

[pvanv]

Re: Tohatsu High Altitude Jet Kits for the MFS15C

That kit is for up to about 9840 feet. There may be others; I would have to consult with Tohatsu so they could check the jetting charts. Odds are that occasional use at 13,000 feet would be OK. Checking plug color would tell the answer. In the US, we don't often have that kind of application, so data would be limited.

 

[Sea Rider]

Re: Tohatsu High Altitude Jet Kits for the MFS15C

What would be the issue starting a 2 stroke 30 HP engine at 13-13.5K feet high that has standard factory jets ? Will engine start normally, will be hard to start, will perform real lousy ? Probably will lose 50% of it's total power at that height. See if possible to check with Tohatsu lean jets for max height use for 5-8-18-30, 2 stroke engines, thanks.

Happy Boating

 

[pvanv]

Re: Tohatsu High Altitude Jet Kits for the MFS15C

Should start OK; will be drowning in gas. The typical symptoms would be like running at 1/2 choke or more: low power, plug fouling, and carbon buildup.