thermo unit assy Question

[sabsab]

Have a 1993 C40 elrr yamaha. Ordered a new thermo unit assy and when removing old unit and found some lube in and around old thermo unit assy. Looked in by manuals but can not find anything indicating applying lube when servicing or replacing unit. Does some one know what kind of lube is used if any? Seems like it would interfere with operation since it heat activated. Or maybe its used to help with corrosion.

 

[rodbolt]

Re: thermo unit assy Question

by all means spray the oring with a bit of two stroke oil at installation.
the heat comes from the stator lighting coil green wire current,changes to blue behind the electrical panal and the good ground connection at the black wire to block.
they can be tested with a 12V battery 2 jumber wires and a scale or set of calipers.
as the C model 40 is premix and fuel flows past the needle on the thermal unit then seeing oil in the pssages may be a good thing.
a failed lighting coil will cause an extremly rich running issure as well as a failed thermounit.
may wish to test a bit and try to understand how the enrichment system works.