dissecting an earthquake chainsaw

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The shape and weight of the crank counterweigths are critical in the balancing of the assembly. The big end bearing is squished between the crank halves from the start.
 
The missing chunk of the lobes may affect case compression?
I'm not sure of the purpose, but I believe the shape is intentional. Perhaps it has something to do with the offset crank journal?
 
I'v got my eyes on a few Zenoah cranks. G621 and G5000 are built the same way - 2 part crank but the counterweights are the same shape. GZ 400{ Ryobi} are 3 part cranks with identical counterweights. I'v got other H543 to dissect and will see that crank. I think this one was just deffective from factory. Edit a Shindaiwa 490[488] crank is built like that{2 part} with even counterweights and 12mm stubs.
 
Well I picked up a new craftsman 42cc(not the poulan 42cc) and took a peek inside. Its cylinder is different than the usual g4500 and 5200 clone, the intake is oval instead of the heart shape. The exhaust port has a large taper going from round at the cylinder wall to square at the exit. It has a huge catalytic converter. Its heavy for a 42cc especially compared to my ryobis. These are made for mtd.
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I think these are made on the G450 case. I saw one of the 42cc versions sold as Cobra chainsaw on Ebay.uk. My other H 543 has the same crank with the weird looking lobes. The saw looks like some hack changed the crank and left the same bearings, The clutch seal on both saws was messed up.
 
Does anybody know what carb comes on the 41cc version? I'm trying to get either a repair kit or replacement carb. I searched the thread and elsewhere but so far have not found it.
Thanks,
Paul
 
Thanks Nathan! I also sent an email to Moreoutdoors4u to see if they can provide any info on a rebuild kit. I'll post whatever I find out.
Paul
 
Well I picked up a new craftsman 42cc(not the poulan 42cc) and took a peek inside. Its cylinder is different than the usual g4500 and 5200 clone, the intake is oval instead of the heart shape. The exhaust port has a large taper going from round at the cylinder wall to square at the exit. It has a huge catalytic converter. Its heavy for a 42cc especially compared to my ryobis. These are made for mtd.
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made for older mtd

46cc

last 38cc 40mm monster
 

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Hello. after a long time i got the inspiration to assemble my H 543. The crank, cylinder and piston were toast. So here is my version of the junk pile saw: chinese crank, cylinder and piston from a strato clone. The strato engines have a intake block with blank strato ports. Normal carb and cat mufler.
 

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Im going to do an autotune conversion on one of my chinese saws since i have all of the parts now.
 
I have to make a steel sleeve on the right side of the crank to replicate the dimensions of the original. .H 543 crank has 12mm left side and 15 mm on the right side. The oil pump is like the one in the Redmax G5000 and clones. The worm gear is made from 2 pieces : G5000 exterior and G3800 interior part. The clutch bell is a chinese piece made for Redmax G3800 and clones like the Earthquake 37 cc. Is a rim drive unit. You can find it on Ebay uk.
 
You have to know that this H543 is a Zenoah saw. So the cylinder is allmost a direct fit. Allmost. The bolt spacing on the intake is bigger on the Husqvarna. So i have to use the original intake block with a twist: two litlle holes from the strato ports to intake.
 
It starts and revs. Seems like the ignition is limited. After a tachometer check i will adjust the carb.Wonder what rpms will turn. The mufller mod seems a little to much.
 
The weird looking crank is the original. The nicer one is chinese. The chinese crank was in a strato clone. Allso the cylinder and piston are from the same engine. 40cc . This is a experiment to see if will work. The flywheel is also chinese . The taper of the crank is diferent so i had to use the chinese one . The saw starts very easy.
 
I got the saw for 80$. Piston problem my foot. The parts to make it go to expensive , so this is the only way to revive the litlle beast. It souns angry with the muffler mod i made.The limited ignition make it more .
 
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