028 bogging when warm

[ja1724]

On the piston/ring sizes I found the following from Baileys:

Q. I have a 028 WB Stihl, the piston measures 42 MM. Will this ring work for me?

A. There are no specs on any 028 WB that ever came with a 42mm piston. That unit came with either 44mm or 46mm, using 44mm x 1.5mm & 46 x 1.5mm rings respectively. We can investigate it further if you would like to give us a call with the saw in hand.

Yet on Sawparts.net they show the following:

Model C.I. Bore Size BHP
-------------------------------------------------------
Stihl 028 WB & AV 2.92 42mm 3.0
Stihl 028 WoodBoss 3.07 44mm 3.2
Stihl 028 Super 3.18 46mm 3.4

WTF ?

 

[Mad Professor]

Caber makes rings that will fit, 42 X 1.5 mm:

http://www.caberpistonrings.com/eng/cataloghi.php?sez=gardening

 

[Fish]

Here is a similar thread.

http://www.arboristsite.com/showthread.php?t=126563&highlight=42+mm&page=3

 

[ja1724]

Well, I ordered the 42mm x 1.5mm set that baileys listed for an 024 saw. Hopefully they fit the 028WB. I'll throw them on when they get here, put her back together, run a compression test, then she how it runs.

I may look for one of the electronic ignition mods.

Thanks for all the help guys. I really appreciate it!