[Milsurplus] [armyradios] PU-181 Generator Fuel/Lube

[J. Forster]

I don't know about the weight issue, but in playing with small engines we
always used SAE 30. 1:32 is 4 Oz oil / gallon gas.

It may be that over time, the amount of oil was reduced.

Two-stroke engines are noted for plug-fouling issues, especially if they
are run for short periods of time. The manual reccomendation may be to
reduce plug crud.

I'd also note that most all gas in WW II was leaded. Today, it's virtually
all unleaded. I believe there are additives that replace the lead function
in modern gas. The lead was used to increase the octane rating, but that
is likely unimportant w/ your engine. Another function was valve
wear/erosion protection. That may be an issue.

There are 'small engine' groups. You might find more answers there.

FWIW,

-John

=================




> OK Wise Guys - here's a question for you regarding engine oil and
> concentration.
>
> The PU-181/PGC-1 is a 2-stroke gas generator rated at 300W, 240/120 VAC.
> It uses a Jacobsen GE-12F engine.  The generator is designed for the PGC-1
> TTY terminal but also for general purpose use.  It has a completely
> shielded ignition system - it is radio friendly. This same engine is also
> used to power the GRC-9 DC generator adaptation.
>
> The placard on the fuel tank advises a *16:1 fuel-oil ratio*.  It states
> to
> use SAE 10 weight below 32 degrees F and SAE 30 for operation above 32
> degrees F.
>
> However, the Tech Manual TM11-943 "Engine Generator PU-181/PGC-1" (US Army
> 1951) states to use a *32:1 fuel-oil ratio* and it says to use SAE 10 lube
> oil, it says nothing about SAE 30 or temperature.
>
> So regarding mix ratio, which is it?  I don't know if there were any
> post-1951 tech advisories that addresses this apparent discrepancy.
>
> Comments?  Thanks
> Tim
> N6CC
>