PP3516 Drive - The Saga Continues

Bobby Kirbos · Oct 13, 2017

Oh this gets better and better....

---------------------- INFORMATION ----------------------
According to the Bailey's web site, drums for the following saws are all interchangable:
Stihl 017, 018, 019 T, 021, 023*, 025*, MS 170, MS 171, MS 180, MS 181, MS 190 T, MS 191 T, MS 210, MS 211, MS 230*, MS 250* (Chainsaws with asterisk usually use .325 pitch chain)

AND

The drive dimensions for the above are the same as the drive spur for my PP3516.

Armed with this knowledge, I found an Oregon Powermate rim & drum kit that comes with a 3/8LP-7 rim (#523046X). If I want to go to 0.325-7, I need kit #100961X.

YEAH BABY!!!!!!

These drums don't come with the bearing. I still need Timken bearing #B57 (5/16 x 1/2 x 7/16).

OR
Just band the bearing out of the old drum and use that.

---------------------- QUESTION ----------------------
The factory spur drive has an "OD" of 1.2". If I did my math correctly, that works out to a chain speed of 32.1mph. The rim has an OD of 1.4", which works out to a chain speed of 37.5mph -- a 15.6% increase.

The questions:

Do I need more oil on the bar due to the increased speed?
With the chain moving at a faster speed, AND since the oil pump/flow rate is not adjustable, should I thin the bar oil to make it easier to get through the oil system?

---------------------- NOTES ----------------------
The math:
D = drive spur or rim OD in inches (where the bottom of the chain rides)
RPM = should be self explanatory (PP3516 under load is 9000RPM)
pi = 3.14
(D * pi * RPM) / 1056 = chain speed in mph

The first part of the equation gives you inches per minute. Divide by 1056 to convert inches per minute into mph.

Replacement rims:
0.325-7 -- Oregon #18720
3/8"LP-7 -- Oregon #14892

happysaws · Oct 13, 2017

Bobby Kirbos said:
Oh this gets better and better....

---------------------- INFORMATION ----------------------
According to the Bailey's web site, drums for the following saws are all interchangable:
Stihl 017, 018, 019 T, 021, 023*, 025*, MS 170, MS 171, MS 180, MS 181, MS 190 T, MS 191 T, MS 210, MS 211, MS 230*, MS 250* (Chainsaws with asterisk usually use .325 pitch chain)

AND

The drive dimensions for the above are the same as the drive spur for my PP3516.

Armed with this knowledge, I found an Oregon Powermate rim & drum kit that comes with a 3/8LP-7 rim (#523046X). If I want to go to 0.325-7, I need kit #100961X.

YEAH BABY!!!!!!

These drums don't come with the bearing. I still need Timken bearing #B57 (5/16 x 1/2 x 7/16).

OR
Just band the bearing out of the old drum and use that.

---------------------- QUESTION ----------------------
The factory spur drive has an "OD" of 1.2". If I did my math correctly, that works out to a chain speed of 32.1mph. The rim has an OD of 1.4", which works out to a chain speed of 37.5mph -- a 15.6% increase.

The questions:

Do I need more oil on the bar due to the increased speed?

With the chain moving at a faster speed, AND since the oil pump/flow rate is not adjustable, should I thin the bar oil to make it easier to get through the oil system?

---------------------- NOTES ----------------------
The math:
D = drive spur or rim OD in inches (where the bottom of the chain rides)
RPM = should be self explanatory (PP3516 under load is 9000RPM)
pi = 3.14
(D * pi * RPM) / 1056 = chain speed in mph

The first part of the equation gives you inches per minute. Divide by 1056 to convert inches per minute into mph.

Replacement rims:
0.325-7 -- Oregon #18720
3/8"LP-7 -- Oregon #14892

To answer your questions,

A little more bar oil wouldn't hurt, although an extra 5 MPH is not a very significant increase in speed.

You can mix diesel fuel into the bar oil to thin it and make it flow better.

The diesel fuel shouldn't effect the lubricity of the bar oil, it will only make it less viscous

You will have to experiment what ratio of diesel to oil works best, start with about a 4:1 ratio of oil to diesel.

Bobby Kirbos · Oct 23, 2017

UPDATE - It DOESN'T work.

The OD on the Stihl drum is about 0.040" larger than the Poulan drum. I can make it fit, but it rubs the chain brake and doesn't turn freely. It does turn, but it binds.
I guess I bought a drum for my Huztl build...