Chainsaw Repair

I went back to the old guy who gave me the pm 800 and dug around in his garage. Found a 36" mac bar he apparently used with that saw. 36TMX63SN. Seems to fit. I'd really like to use this saw, but that's way more bar than I need. Sure would like to get around 24". Did they originally offer those saws with 16" bars? That seems way too small to me.

TMX is Windsor's designation for the 10-series Mac mount (Oregon's D276).  Made for your PM800.  A PM800 is a 10-series saw and not a Large Frame Mac (250, SP125, etc), despite it being larger than a 10-10A or other smaller 10-series saw. 

The Large Frame Macs that this thread covers are a completely different series (with a completely different mount).  To confuse things, McCulloch did sell some 'slim line' bars that were intended for use on both Large Frame Macs (with the right bar plates) and 10-series Macs (with stud spacers).

The 82cc 10-series Macs (SP80/SP81/PM850/PM805/PM800/PM8200/DE80) were typically sold with 20-36" bars.  Doubt many were sold with 16" bars.  Jon1212 had several TMX and D276 bars in various lengths.  Probably still has some.  There are NOS and used bars on eBay too, including several 28" bars.   

You can also use an Oregon D176 mount bar on your PM800.  The D176 is Oregon's current 'multi fit' mount, intended to work on most larger Echos, XL-series Homelites with 5/16" studs, most older medium/large Poulans, and 10-series Macs.  IIRC, they still produce them in lengths up to 24".  They have been made in several lengths in the past.

If you adapt a large Husky mount bar (or similar) to a 10-series saw, be sure to cut oil channels from the adjuster holes to the chain groove.  That's how these saws oil.  D276, D176, and TMX bars all have these channels.  Like an A041 or K041 Poulan/Echo bar.  That reminds me................you can often use a K041 mount bar on a 10-series (or a D276/TMX on a K041 mount saw) without modifying anything...