I must have bent the metal ring on the inside of the chain break as it will no longer fit smoothly onto the machine. Solutions? Source of new chainbreak for H 50 special? Thanks

valve not closing is from a bent valve. Black soot is from over fuelling and incomplete combustion. Oily chamber is oil from the rings. It si possible that more than one valve is bent as it occurs from turning the engine over without letting of the rockers when adjusting the valve timing.

hi,

Sooner or later, every bike will need a new chain and sprockets. Once a chain begins to wear, its pitch changes and wears the sprocket teeth. Then the chain begins to wear even faster. Then it's time for a new chain, and a new pair of sprockets.
The rear wheel on my motorcycle had been misaligned (I had used the inaccurate etched indicators on the swingarm-rather than a ruler against the sprocket-to set wheel alignment) and ridden hard through a gritty, salty winter. The rear sprocket was in rough shape, and the chain was making lots of popping sounds as the bike went down the road.
Changing a chain is a fairly basic job that requires a chain breaker / riveting tool and whatever is needed to remove the rear wheel and sprockets. It's nice to have a blow torch and a torque wrench on hand for this job, too.
The ingenious Terra-X chain tool is made in Australia out of tool steel, and weighs just 150 grams. A big hollow bolt threads into the bigger of the two holes, and is used when pressing outer plates onto new master links. A smaller bolt with a pin can thread into the hollow bolt, and is used to push link pins out of old chains or to peen new master link pins by pushing them against a grub screw threaded into the steel body's other hole. That little grub screw with a rounded steel end screws into the smaller hole of the chain breaker. It fits into and peens the hole of the new master link.
When changing a chain, the first step is to loosen the bolts on the front sprocket. It's good to get those loose while the chain is still on the bike, partly to avoid putting undue stress on the transmission, and partly to avoid getting deep into the job and finding that the front sprocket bolts are stuck. In this case, the small allen bolts needed a bit of heat to come undone.
After the bolts are loose, it's time to break the chain. With the Terra-X chain tool, you remove the small grub screw and use the small bolt with the pin to push out one of the chain's pins. No grunting or swearing required.
Then comes sprocket replacement. Six nuts on the rear sprocket, the two bolts on the front sprocket, and that step is done. I had a torque wrench handy, so I could get the torque values just right when putting everything back together.
The next step is the big one: installing the master link that joins the ends of the new chain together. The master link comes with a little bag with some X-Rings, a master link, and some sticky tan lube. Smear the lube on the pins and inside the X-Rings, then begin to assemble the master link around the two ends of the chain, making sure to get the X-Rings in the right spots.
Pressing the outer plate onto the master link is the hardest part of the job. I removed the pin bolt from the Terra-X tool and used the hollow bolt to push the outer plate onto the master link's pins. It took a few tries, but eventually I got it in the correct position.
After the sprockets are on and the master link is in position, the master link's pins need to be peened. With the Terra-X, the pin bolt pushes the master link pin against the grub screw's steel ball, and flares the pin. It takes a lot of effort-mostly because it's not easy to get a lot of leverage on tools when they're underneath a motorcycle.
Position the wheel for proper chain tension, torque everything to the correct specs, and you're back on the road. The new chain is smooth, nearly silent, and ready for thousands of miles of high-speed running.

hi,

Sooner or later, every bike will need a new chain and sprockets. Once a chain begins to wear, its pitch changes and wears the sprocket teeth. Then the chain begins to wear even faster. Then it's time for a new chain, and a new pair of sprockets.
The rear wheel on my motorcycle had been misaligned (I had used the inaccurate etched indicators on the swingarm-rather than a ruler against the sprocket-to set wheel alignment) and ridden hard through a gritty, salty winter. The rear sprocket was in rough shape, and the chain was making lots of popping sounds as the bike went down the road.
Changing a chain is a fairly basic job that requires a chain breaker / riveting tool and whatever is needed to remove the rear wheel and sprockets. It's nice to have a blow torch and a torque wrench on hand for this job, too.
The ingenious Terra-X chain tool is made in Australia out of tool steel, and weighs just 150 grams. A big hollow bolt threads into the bigger of the two holes, and is used when pressing outer plates onto new master links. A smaller bolt with a pin can thread into the hollow bolt, and is used to push link pins out of old chains or to peen new master link pins by pushing them against a grub screw threaded into the steel body's other hole. That little grub screw with a rounded steel end screws into the smaller hole of the chain breaker. It fits into and peens the hole of the new master link.
When changing a chain, the first step is to loosen the bolts on the front sprocket. It's good to get those loose while the chain is still on the bike, partly to avoid putting undue stress on the transmission, and partly to avoid getting deep into the job and finding that the front sprocket bolts are stuck. In this case, the small allen bolts needed a bit of heat to come undone.
After the bolts are loose, it's time to break the chain. With the Terra-X chain tool, you remove the small grub screw and use the small bolt with the pin to push out one of the chain's pins. No grunting or swearing required.
Then comes sprocket replacement. Six nuts on the rear sprocket, the two bolts on the front sprocket, and that step is done. I had a torque wrench handy, so I could get the torque values just right when putting everything back together.
The next step is the big one: installing the master link that joins the ends of the new chain together. The master link comes with a little bag with some X-Rings, a master link, and some sticky tan lube. Smear the lube on the pins and inside the X-Rings, then begin to assemble the master link around the two ends of the chain, making sure to get the X-Rings in the right spots.
Pressing the outer plate onto the master link is the hardest part of the job. I removed the pin bolt from the Terra-X tool and used the hollow bolt to push the outer plate onto the master link's pins. It took a few tries, but eventually I got it in the correct position.
After the sprockets are on and the master link is in position, the master link's pins need to be peened. With the Terra-X, the pin bolt pushes the master link pin against the grub screw's steel ball, and flares the pin. It takes a lot of effort-mostly because it's not easy to get a lot of leverage on tools when they're underneath a motorcycle.
Position the wheel for proper chain tension, torque everything to the correct specs, and you're back on the road. The new chain is smooth, nearly silent, and ready for thousands of miles of high-speed running.

Assuming you replaced the chain because it was worn? The length of a chain increases as it wears, and the chain rings wear to match the longer chain. When you fit a new chain, it is shorter, doesn't fit the worn ring/s, and there is a risk that the chain will jump - most often on big and middle rings. If you let your chain wear a lot, you may need to replace your chain rings and possibly your cassette too,

I assume you actually mean the metal ring that holds the small round case that the bobbin itself sits in. There are usually two arms that swing in to hold that larger metal ring in place and then there is a plastic and metal piece that sit behind the large metal ring. fit the plastic piece that may look somewhat like a scoop next to the metal piece that usually has the post the the bobbin fits onto and has a quite sharp tooth on it. The metal ring then goes on to hold those two pieces in place and the two arms swing in to hold the metal ring into place. The bobbin or bobbin case now can be put back in. Hint on metal ring placement: they almost always have a notch that goes at the very top where the arm on the bobbin case sits in when it is in place. You may find it easiest to do this with the machine laying on its back so you don't have to have 4 hands to hold everything in place while putting everything back in.
Good luck!

It can be a little tricky!

If you are referring to chain break band

Tools you will need:
1/2 Socket (to remove bar nuts)
T25(torq) or you can use a Flathead screw driver but is a little harder.

Remove 2 bar nuts,Clutch cover,bar,chain, 2 screws on black bar handle right behind clutch cover(this is needed because there is a hidden screw there for the chain break) You will need a new chain brake (my guess is that it is part # 530071893 aprox $15) but you will want to verify that with your model number.

You should see the chain break assembly, 3 - T25 screws are visible after the clutch cover is removed(note sometimes you have to clean saw dust to make screw head visible) the other T25 screw is hidden under the black bar handle. Once you remove all 4 screws on the chain brake you will be able to pull it off.

Installing the new one is the tricky part because if it is set(or break is on) you will have a hard time putting it on.One of the easiest ways is to focus on it near the muffler you will see that a metal 3 pronged gear fits into the plastic part of the chain break handle.and if the band is too tight to fit over the clutch drum you will have to carefully reset it by applying pressure onto the area that has the 3 pronged gear and chain break handle make sure that the handle is pushed forward all the way while you apply pressure then slowly pull chain break handle back till you hear a "snap" this resets the chain brake spring and the band should now fit over the clutch drum.Now, proceed with putting back together 4 chain brake assembly screws,2 handle screws,and bar,chain,clutch cover,and 2 bar nuts.

Please note it is important that you apply quite a bit of pressure onto chain break area where metal (3 pronged) gear fits into handle while resetting or when you reset it the metal part can cut into and damage the plastic piece in the chain break handle.

You can see a breakdown here: http://www.searspartsdirect.com/partsdirect/part-model/Poulan-Parts/Chainsaw-Parts/Model-P4018WT/1324/1503220/P0506041/00002?blt=06&prst=0&shdMod=P4018WT

Hope this helps!

The starter clutch needs to be replaced. At the other end of that chain is a wheel with a couple slots cut at angles. Inside each of these slots is a small cylindrical piece of metal. The whole unit fits over the end of the crankshaft and because of the angle of the slots those cylindrical pieces of metal (which move freely in the slots) will be forced against and grip the crankshaft when the starter is operated. If they become worn down they are no longer able to exert enough pressure on the crankshaft in order to turn it. Buying a starter clutch 2nd hand is not recommended. If you are unable to source one from a bike shop, try and have them made. Take the old ones to an engineering shop. Unless you know how to temper/harden metal of course.

The left blade on a BD 2300 bread maker did not turn when neading the dough. I took it apart by removing the six screws in the bottom of the case and the screws inside around the bottom outer edges of the metal insert. I then removed the screws holding the motor assembly to the base. I found that the metal plate attached to the paddle shaft driven by the gear had torn through the plastic gear, and was no longer driving the paddle. I made a new plate with the end bent down 90 degrees so that it fitted into a slot in the plastic gear. This is much stronger and the breadmaker now works fine. This is a weakness in the design and the failure could occur on either paddle. failures of the left paddle could be due to the toothed belt breaking, this drives from the right paddle gear. There is also a belt between the motor and the left paddle gear.

If your thread is breaking while your doing embroidery, there could be a few different reasons. 1. The fabric in the hoop has to be as tight as a drum. When you "flick" it with your finger it should give you a poping type drum like sound. If the fabric can flex while the machine is sewing, you will break thread everytime. Also you need to be using the correct backing on the fabric. Your machine has a embroidery advisor that will aide you in choosing the right style of backing for the type of fabric your sewing.
Turn the machine off for the following:

2. Change your needle to a size 12 universal for most embroidery.
3. Inspect the inside hole of the foot for needle strikes. If the needle has struck the plastic "R" foot, your thread could be getting caught on it.
4.Remove the needle plate and inspect the hole for the same rough edges, there can't be any. Cut a strip of a metal sanding paper the size of the hole and floss the hole if needed to remove the burr. DO NOT ENLARGE THE HOLE. Simply smooth the rough edge. The hole size is critical for proper stitch formation. If the plate is damaged to the point metal is missing from inside the hole, buy a new plate.
5. Remove the bobbin case grey cover and the black bobbin case and inspect the metal round thread hook edge for roughness as well. Smoothing the hook is the same as the plate, you can't change the shape of the metal so don't go crazy sanding it. Just smooth the edge. The thread "races" around this area so smooth metal is a must.

I hope this helps, good luck!

Don't use a rubber mallet! It shouldn't take that much force! Make sure the piston ring is compressed enough so it will fit inside the cylinder as you slide it down over the piston. Be very delicate! It doesn't take much effort to break a piston ring or screw up the crank bearings. Just take your time and make sure everything is lined up and extremely clean.a thin coat of 2-stroke oil on the piston, rings, and inseide the cylinder will help protect everything - just make sure you're working in a clean environment where there's no dirt and grime for the thin coat of oil to attract.