I will WD-40 the shafts and what not, I have the L and H set at 1 turn out which is where they were before I touched it, Should I go a 1/4 more? What should I notice by adjusting L in and out and what about the H? Is there any I can check and clean or lube with the clutch? I only have been messing with this in between other projects. I Honestly don't plan to really ever use this saw, I may try it out in some wood but other wise it is going on the shelf to be ran here and there.
Hi, Homelite Blue XL-12 Saw, Looking for some information I'd like to rehab it.
- Thread starter JOE.G
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At idle speed, turning the L screw clockwise will lean out the mixture and counter-clockwise will richen it. Turn it in until the speed just starts to drop, then out until max speed is reached, then about 1/8 turn more out. The H screw is set at wide open throttle - turning the same as the L screw. You are listening for a burbling sound that clears up as you start cutting. There are some good videos on youtube. The weights on the clutch need to move freely. They are spring loaded and centrifugal force causes them to fly outward. As long as you can move them by prying outward a little, they should be fine. The springs should pull them in firmly - so the chain doesn't turn at idle speed - about 2700 rpm.
Here is a C51 I worked on. Listen to the sound when I start cutting at about 0:41 seconds into the video. It sounds rough but clears up when I start cutting.
c51b - YouTube
c51b - YouTube
I messed with it some more, It is idling fairly smoothly at around 1,800 RPM and the chain is still spinning, I checked RPM at full throttle and I got around 7,500 RPM May keep climbing if I hold it wide open. I played with the L and H and I think between 1 to 1-1/4 out sound best. I think ill pull the side cover and check weights and maybe WD 40 them and see if it'll stop.
Either the weights are stuck out (rusted) or the springs are weak or something is binding the clutch drum to the clutch or crank - maybe locked up bearing or washer in the wrong place. Does the chain and clutch drum turn freely with the engine off? If so, sounds like weak springs.
Wide open, you should get close to 9000rpms.
Yeah it was pretty caked up when I took the cover off while cleaning it the first time, I'll probably mess with it again on Wed. Could I have over tightened the nut holding the clutch on? The chain will spin by hand with the saw off but not easy. I really appreciate all of the help I am not new to motors but and not even saws but this is my first old one and things are a little different and I just don't want to mess anything up trying to keep it as original as I can.
Probably couldn't over tighten the nut if it's assembled correctly. Make sure any spacers/washers are in the correct spots. You could loosen the nut to see if it turns more freely. Does it have a bearing or bushing?
Just a hint about the H jet adjust. If adjust too lean you can ruin your saw easily. You can also search videos about the proper sound for adjusting the carb for 4 cycling. (not all saws will give the 4 cycle sound) I use a IR temp gauge to check that a saw is not overheating due to incorrectly adjusted carb.
Do not adjust the H jet for max rpms and leave it as such. It's not just simply using a tach and adjusting the H jet for rpm's.
Tuning by ear adjust the H jet for max rpms while reving and then keep backing out CCW until the rpms drop off and you hear what sound like burbling or the saw is missing heart beats. (this is the rich condition and excess fuel hitting the piston to keep it cooled) Oil is not the major coolant on a chainsaw, it's excess gas hitting the piston and this is why running rich is important.
If you simply adjust the H jet for max rpms you might get lucky and use the saw for quite awhile with no problems doing light cuts on and off the throttle but if you even get into a long full throttle full bar cut in a big log for more than 30 seconds the piston can/will overheat fast, swell into the cylinder wall and the saw will appear it's bogging down from a overload but it's actually the piston overheating and swelling into the cylinder wall (friction) with the saw engine eating itself. You remove the saw from the log, piss rev few times, it cools little bit, it picks up speed and back into the cut and you are ruining your saw and you are not readily apparent of such until it's too late and even then often times you do not really know what happened so fast.
You install a new piston and jug and use the saw for quite a spell and then back into a long full bar cut and it happens again.
Also adjust the L jet little on the rich side CCW. If the L jet is adjusted wrong the throttle piss rev will usually bog.
I've found that when the block jug temp on most chain saws starts reaching or exceeding 275 degrees F the block is getting too hot. Most generally a lean saw's temp will head towards 275-300 really fast in a full bar cut, but when a NON-MODDED chainsaw is adjusted correctly and all else is ok the temp will be slow getting to 250 and stabilize around such.
You can check/monitor such with a IR thermometer when in a full bar cut with a sharp chain.
Do not adjust the H jet for max rpms and leave it as such. It's not just simply using a tach and adjusting the H jet for rpm's.
Tuning by ear adjust the H jet for max rpms while reving and then keep backing out CCW until the rpms drop off and you hear what sound like burbling or the saw is missing heart beats. (this is the rich condition and excess fuel hitting the piston to keep it cooled) Oil is not the major coolant on a chainsaw, it's excess gas hitting the piston and this is why running rich is important.
If you simply adjust the H jet for max rpms you might get lucky and use the saw for quite awhile with no problems doing light cuts on and off the throttle but if you even get into a long full throttle full bar cut in a big log for more than 30 seconds the piston can/will overheat fast, swell into the cylinder wall and the saw will appear it's bogging down from a overload but it's actually the piston overheating and swelling into the cylinder wall (friction) with the saw engine eating itself. You remove the saw from the log, piss rev few times, it cools little bit, it picks up speed and back into the cut and you are ruining your saw and you are not readily apparent of such until it's too late and even then often times you do not really know what happened so fast.
You install a new piston and jug and use the saw for quite a spell and then back into a long full bar cut and it happens again.
Also adjust the L jet little on the rich side CCW. If the L jet is adjusted wrong the throttle piss rev will usually bog.
I've found that when the block jug temp on most chain saws starts reaching or exceeding 275 degrees F the block is getting too hot. Most generally a lean saw's temp will head towards 275-300 really fast in a full bar cut, but when a NON-MODDED chainsaw is adjusted correctly and all else is ok the temp will be slow getting to 250 and stabilize around such.
You can check/monitor such with a IR thermometer when in a full bar cut with a sharp chain.
Okay, The saw is idling around 2,000 RPM and and max RPM is still around 7,500 but the saw sounds good and has good throttle response. I took the chain gear off and I oiled the bearing in it a little bit and put it back together and the chain now does not spin while idling. I have no plans of using this saw I just wanted to get it running, I am going to put it on the shelf and start it once in a while. I would like to replace the bar and chain as they are quite worn but I want them to be from the correct time period.
If you happen to buy a bar and chain from anyone remind them to add additional cardboard or something to both ends of the bar to keep it from cutting it way out of the shipping carton. The edges of the bar are sharp.
I've seen this happen more than once and the carrier does not even care if parts and pieces falls out, they just deliver an empty box to the person on the label.
AND you have to keep a heads up, several bars DO NOT FIT that saw even though advertised as such. (close but no cigar)
I've seen this happen more than once and the carrier does not even care if parts and pieces falls out, they just deliver an empty box to the person on the label.
AND you have to keep a heads up, several bars DO NOT FIT that saw even though advertised as such. (close but no cigar)
I used the saw a couple day's ago and cut up a cedar tree, Saw was smoother then I thought it would be and cut well, I am still using a worn bar and chain. So far the saw has started everytime on the 3rd pull cold.
