This is a unique problem to me, I have a Mac 610 (don't make fun i luv it) it runs awesome in normal position (Bucking) but when felling (horizontal cut) it bogs out and sputters then dies.I know it's a carburetor problem. at least i believe it is. if I adjust it rich 1- 1/2 it gets worse but when I lean it down to 3/4 it gets better but very hard to start and keep running. I usually run around 1 turn out and 28:1 -32:1 mixture ratios it has a Walbro carb HDB 7A I think it's flooding but before I tear the carb apart looking for needle problem or gasket failure I was wondering if anyone could shed some light from their own experiences on this problem
Thanks in advance for any tips ........
My first inclination would be to look in the gas tank and check that the fuel line with the filter is free moving and not binding or restricted.
Thanks .......
DUH I feel a bit dumb not even thinking abt that, see (sometimes we complicate our own lives)
GOING OUT TO CHECK IT OUT NOW
also that the filter is connected to the fuel line. If the filter is off the line won't necessarily fall to where it needs to be.
Also check the fuel line for cracks, that is an old saw and lines deteriorate with age. If possible get the saw pressure/vacuum tested, it may have a leaking crank seal.
Right on guys. Might not be in the carb at all.
Quote from: sawguy21 on February 03, 2020, 12:59:25 PM
Also check the fuel line for cracks, that is an old saw and lines deteriorate with age. If possible get the saw pressure/vacuum tested, it may have a leaking crank seal.
not to sound sarcastic yes it is old but it runs like new (usually) as I keep lines replaced and parts replaced sorry but it sounded like you inferred the original lines were probably still being used LOL Thanks for the tip nonetheless it did make me laugh
I've never run a mac 610, not familiar with them. My 288xp took a spell a couple years ago about like you described, had a couple of AV mounts that were worn badly, allowed it to pinch off the fuel line somehow when i would fall timber with it. Bucking logs it ran perfect. New AV mounts and its not done it since.
OK I checked the line out really good, and it was a bit too long so I shortened it and I think I am going to go a head and get a stone filter as it has one of those plastic screen types in it ( i had to get that when my parts store didnt have the stone ones last year) but with all that stated the issue isn't in the supply line sad to state I decided to run it with out the air cover on for a quick check and when horizontal it actually started spraying fuel on my hand so yeah it's a severe flooding issue like the needle is stuck open or something I guess I need to try to find me a rebuild kit but last time I rebuilt it I wasn't happy with the kit i found it didn't include a meter gasket and a base gasket so I was forced to use the old ones which may very well be the problem. any tips on what might be causing the flooding is appreciated like what to look for Thanks everyone
Pineridge: you stated (had a couple of AV mounts that were worn badly,) just FYI what do you refer to when you state AV mounts ? I'm a retired hvy equipment mechanic and whereas I feel quiet comfortable working on chainsaws my venacular or lingo probably isnt correct LOL or familiar
Anti vibration mounts.
my Stihl fuel line is molded and got a crack in the angle. so would run fine on a full tank, but bad or die at half full. could be influenced by position a well.
The 610,650 timber bear 3.7 are probably the most under rated saws of all times.Other that being rather heavy for 60 cc they are rather robust .McCulloch probably made a zillion of them and more were sold at places like K-mart than at McCulloch dealers when there were any. I've got three in my shed that do run and run well although I don't use them that often .
One of those models belonged to my departed father who if he would have lived would be 100 years old .Dad did a little soup up on it and in the day it would outrun a Stihl 042 .It's in great shape .Mine that was used for about 9 years when I sold fire wood is not nearly as nice .The one I bought for my son looks nearly new and had the original Mac bar and chain .It died early in it's life from a bad ignition coil .At the time it was a cheap fix .
yes sir it is a heavy saw indeed, but easy to work on, all steel case,except for air cleaner cover. mine is a early 80's model and yes 60 cc = enough to power through without bogging down on black oak. I really like it 8)
well I have finally discovered what it was I believe, The choke plate was binding on half choke keeping it from opening all the way which probably happened some time when it was cold and I used too much force to open it lol;
I was about to tear in to the carb when I noticed that something wasn't right (the choke is the first thing to disconnect ) and this made sense to me LOL
Thanks everyone for the tips it did put me back in the mindset of check the easy stuff first before complicating everything
so new linkage or plate, fixed the old one? any pics? good news!
Quote from: doc henderson on February 07, 2020, 10:45:27 AM
so new linkage or plate, fixed the old one? any pics? good new
I have been really busy over the weekend with the wife but I plan on getting it checked out tomorrow sometime, I will get some pics and if can learn this whole pic loading scenario out on this forum I will be glad to share
........................02/10/2020..................