I was desperateRead the owners manual? Who does that?????????
I was desperateRead the owners manual? Who does that?????????
Ya gunna have to hand in ya man card nowI was desperate
There's always You tube.I was desperate
The mystery continues. Check the key on the flywheel, and check the air gap as well. ( business card works for me.)Well she's back to acting up. Shooting blue flames out the muffler on choke then flooding out with fuel coming back through the carb. I'll try brand new fuel today.
Maybe starting to sound like a timing issue?
Will do!The mystery continues. Check the key on the flywheel, and check the air gap as well. ( business card works for me.)
Thanks - I'll see if crank seals are available for the saw.I never made a mistake, thought I did once, but...
I was going to ask you how old it was, as bad crank seals can suck air intermittently and cause contradicting evidence about like your description.
Occam"s Razor FTW!
I'm glad you got her running. Ignore the perfect people and carry on!
I've got a plastic mac that needs seals and that's how it acts. Seals are unobtainium for my little yellow saw, but I'm keeping it until I find or make something fit. It's now been waiting about 20 years. I also have an original Mini-Mac I got from a neighbor a few years back, gotta order in the parts and get her running, likely seals and all soft parts.
No one I know!Read the owners manual? Who does that?????????
Blue flames!? As I recall, blue flames are indicative of chemicals burning or of very high temperatures (trust me, I have first hand knowledge of both). Why those would be coming out of your muffler is the real question. It sounds like raw, atomized fuel is being spat out of your muffler and ignited by the spark in the cylinder. I'd try a new plug, personally. I had a Mac with a bad plug that would load up then "explode" similar to what you previously described and a new plug fixed it. Or, check your plug wire for breaks, tears, or exposed wiring. If the plug occasionally "misses" that would cause raw fuel to be spat out and cause the flames like you are describing.Well she's back to acting up. Shooting blue flames out the muffler on choke then flooding out with fuel coming back through the carb. I'll try brand new fuel today.
Maybe starting to sound like a timing issue?
Thanks for the info. It has a brand new plug. I put in a NGK BPMR7A but the spec sheet calls for a BPM7A. Have just been reading the R might cause problems in the older chainsaws? Could be worth trying a BPM7A.No one I know!
Blue flames!? As I recall, blue flames are indicative of chemicals burning or of very high temperatures (trust me, I have first hand knowledge of both). Why those would be coming out of your muffler is the real question. It sounds like raw, atomized fuel is being spat out of your muffler and ignited by the spark in the cylinder. I'd try a new plug, personally. I had a Mac with a bad plug that would load up then "explode" similar to what you previously described and a new plug fixed it. Or, check your plug wire for breaks, tears, or exposed wiring. If the plug occasionally "misses" that would cause raw fuel to be spat out and cause the flames like you are describing.
The "R" means it's a resistive plug, resistive plugs generally create less RF interference (like anyone cares) but also cause the coil to build up a higher voltage before arcing. This can be problematic if the insulation in the coil isn't able to handle the higher voltage & breaks down. If you go the other way & use a non-resistive plug where one is called for the coil won't achieve as high a voltage causing a less effective spark. With lower voltage comes higher current & that can cause coil issues too.Thanks for the info. It has a brand new plug. I put in a NGK BPMR7A but the spec sheet calls for a BPM7A. Have just been reading the R might cause problems in the older chainsaws? Could be worth trying a BPM7A.
Thanks for the info.The "R" means it's a resistive plug, resistive plugs generally create less RF interference (like anyone cares) but also cause the coil to build up a higher voltage before arcing. This can be problematic if the insulation in the coil isn't able to handle the higher voltage & breaks down. If you go the other way & use a non-resistive plug where one is called for the coil won't achieve as high a voltage causing a less effective spark. With lower voltage comes higher current & that can cause coil issues too.
In short, it's best to use the plug the manufacturer designed the coil for, but I don't think it has any bearing on your current issues... I'd be looking at timing
It seems to. No I haven't. Don't have the gear for that.Sounds like that saw floods way too easily. Have you pressure tested the inlet valve of the carb?
I'll give it a go and report back.All your problems could just be from a carb that is flooding, could be an inlet valve that is not seating, a control lever that is set too high, a faulty diaphragm that is holding the valve open, or a gasket on the wrong side of the diaphragm. A simple (not very good) test is to just hook a tube to the fuel inlet port and blow into it, you can blow about 3 or 4 psi and that should be enough to tell if the inlet valve is properly seated.
Don't be misled by tank vent issues, it is normal for pressure to build up in the tank and if the carb inlet valve will stay closed to at least 8 psi (pop off pressure) it won't cause flooding, however, if the valve open at a lower pressure than what builds up in the tank, you WILL have flooding. This is why it's important to do a proper pressure test on the carb.
Just blew through the fuel inlet barb with everything I've got and it took it without releasing. Will look at getting a mityvac and do some proper testing.All your problems could just be from a carb that is flooding, could be an inlet valve that is not seating, a control lever that is set too high, a faulty diaphragm that is holding the valve open, or a gasket on the wrong side of the diaphragm. A simple (not very good) test is to just hook a tube to the fuel inlet port and blow into it, you can blow about 3 or 4 psi and that should be enough to tell if the inlet valve is properly seated.
Don't be misled by tank vent issues, it is normal for pressure to build up in the tank and if the carb inlet valve will stay closed to at least 8 psi (pop off pressure) it won't cause flooding, however, if the valve open at a lower pressure than what builds up in the tank, you WILL have flooding. This is why it's important to do a proper pressure test on the carb.
I use a cheap bike pump with a psi guage that I got at a yard sale.Just blew through the fuel inlet barb with everything I've got and it took it without releasing. Will look at getting a mityvac and do some proper testing.
OK I have one so I'll try that.I use a cheap bike pump with a psi guage that I got at a yard sale.
Enter your email address to join: