[MRCG] PU-181 Generator Fuel/Lube

[Tim]

Robert Downs wrote to me:
"As I wrote you earlier, although there is no note saying it's been
changed, Change 2 to the 1951 TM has a Lube Order that goes back to 16:1.
The PE-214-C became PU-181/PGC-1.  TM 11-945 has a 1950 Change 1.  The Lube
Order in both the basic pub and the Change say 16:1 of 10 wt.  It took two
fillings of the cap for one gallon of gasoline."

Hi Robert - yep, I missed that - Duh....Change 2 clarified it as 16:1 (the
right ratio in any event back in the day).

But now I am finding something else out  - there are 2 different size
"measuring caps"!!  On my PU-181 the cap holds 2 ounces but there seems to
be a 4 ounce cap (twice as deep as mine - it extends almost to the bottom
of the tank) in the drawing in TM11-945/PU-214B.  (Part number 550 on the
Page 60 drawing.) The plot thickens.

Also, the tank on the PE-162 is only a half-gallon - so the longer, 4 ounce
cap should not fit in that tank.  I'm starting to wonder if the cap in my
tank was actually switched from a PE-162 generator tank some time before I
got it.  So two of THOSE caps fulls yields 32:1....No wonder this is
confusing....More digging needed....

So when a TM says use X Cap fulls, you need to know which cap you have.
Nowhere in the manuals do they directly tell you how many ounces they
actually hold.  Are all you guys following this??  I hope not !  LOL

Thanks for setting me straight on Change 2...(again!)
73,
Tim


On Mon, Apr 14, 2014 at 12:38 PM, Tim <timsamm at gmail.com> wrote:

> 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
>