Chainsaw Repair

 

Quote from: Cut4fun_ on February 06, 2013, 07:07:57 pm

3 of us had a mini gtg today running  muffler modded 550, 550 stock muffler, 346 50cc stock muffler,  346 45cc woods ported, redmax 5000 woods ported. The 2 550's and 346 ran the same chain for testing. Everything ran 3/8 16

We ran a stock with muffler mod 550xp and a stock muffler 550xp back to back with 3/8 16" bars buried for most of whole cuts. 

550 with muffler mod quickest was 12.46 seconds

550 with stock muffler and 1st tank  13.89 seconds

Some observations about these two 550's . . .

The one with the muffler outlet opened up would free run beyond 14000 and go into the ignition limiter. I don't think it had more than two or three tanks of fuel through it?

The other completely original 550 with not a whole tank of fuel run through it would free run at 13740 rpm.

Obviously the mixture was different in these two? Both had been run about about the same amount that day with about a half dozen buried cuts in silver maple.

The outside air temperature was around 27F

I have no clue as to the serial number differences of these two?

Another observation was that I had my completely stock 346XP NE there and it didn't run as fast in the cut as the 550's and there was noticeably less torque. All the chainsaws were running the same 3/8 X 60DL Stihl RSC chain and Oregon Power Match Bar that we swapped onto them.

 If he Kevin did not change the fuel in the new 550 that he got from me then it is running stihl ultra at 44:1