Husk 440 starting problem

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OK it's all apart! When I turn the crank into the compression stroke, I can feel some resistance but not what I would expect for 115 -130 PSI, so I would assume the piston/cylinder is shot. I have ordered new crank seals and now am trying to select which vendor on ebay I should use. The one I am thinking of includes the seals that go between the jug and the case. Other vendors that sell the crank seals and case gasket want almost 1/2 the cost of the complete kit.
That was my reasoning.
Now the last question for now, is how do you remove the spring shock mount from the jug? Is there a screw down the center that needs to be loosened?
 
Once the jug was removed from the case the crank seals just "fell" out. I found the vibration spring is held in place with a 3mm screw so that came out easily. Now I have to ask the owner how much he is willing to invest.
I did see one website had OEM piston and cylinder for $117 but that seems high in price.
 
I watched the 2 part rebuild posted Tomos770 and I have some questions. Should the Loctite sealer be installed in the crank seal groove on the cylinder? He installed it only in the groove of the plastic case. He also used it on almost everything where two surfaces join. Is that the common application? I have some other Loctite products, (Red and Sealer) but I ordered the 518 and Blue which should arrive by the end of the week.
Thanks to all for the instructions.
The owner has opted for the less expensive replacement cylinder and piston. I'll put it together with the understanding that the performance may be less than the original with less longevity.
Regards,
Dan
 
FWIW, I just worked on some 440s. One of the easiest top end rebuild projects in all of chainsaw-land. (impact driver, 4 mm hex, and long torx bit - and its apart and ready for cleaning in half an hour). I did/do use assembly lube rather than 2-cycle oil. Definitely change crank seals whenever you have it split. Carb is "both on one side" (bottom) style - only likely issue is pump diaphragm/alcohol. Start closer to 2 turns out on the carb screws. The fuel (and fuel return) hoses crack just as they come through the housing in ways hard to see. The black plastic-ish thing around the carb is prone to cracknig around the outside, a little bit 'fussy' to seat right. Be careful to get the right flywheel (rarely / never need changing, but...) there are flywheels out there of the same diameter with very different ignition timing to the key position (barely/don't start and don't run). Ignition modules can get cooked, but perfectly suitable replacements are plentiful and cheap. My start is purge, choke on, couple of pulls until you hear the first of igniting. Then choke off, starts right up...
what compression is still start able 120 ? what is min max on compression
 
what compression is still start able 120 ? what is min max on compression
It can vary a little, but below about 90PSI there's no chance it'll start. Around 120PSI is probably startable but won't run worth a damn. 150PSI is ok. 180PSI is good, Above 210PSI you need to consider having fuel above 89 octane & a decent decomp to prevent damage to the starter (both the part & the person)
 
I got it all together! One thing I did find, the blind holes for the carb intake manifold were not deep enough for the length of the screws. I added a lock washer and that did the trick. I had a little trouble removing the wrist pin C clips since they did not have the tang to grab to remove. A little picking with a small screwdriver did the trick. Unfortunately, I did not tighten the flywheel sufficiently, and when I gave it a pull and it started, the keyway on the flywheel sheared. I am now trying to get a replacement flywheel with two week delivery time from Small Engine Power Works. I have seen bad reviews about Power Mower Sales so I discounted them as a supplier. The part number I am looking for is 544874202. Most of the listings on the web have prices in the $40-$50 region with SEPW at a little over $10 plus $7 shipping. I thought I saw two in stock, but when I called SEPW they were out of stock, and needed to get it direct from Husky. My bad at the insufficient torque on the flywheel nut.
 
Pick out the broken pieces of the key and go get another from the hardware store. The flywheel should be OK
Dis-regard the above but you can still run it. Put it on with the original orientation and tighten it down. As long as the flywheel is where it belongs and the nut is torqued down good it will be good. The taper holds the flywheel not the key.
 
I got it all together! One thing I did find, the blind holes for the carb intake manifold were not deep enough for the length of the screws. I added a lock washer and that did the trick. I had a little trouble removing the wrist pin C clips since they did not have the tang to grab to remove. A little picking with a small screwdriver did the trick. Unfortunately, I did not tighten the flywheel sufficiently, and when I gave it a pull and it started, the keyway on the flywheel sheared. I am now trying to get a replacement flywheel with two week delivery time from Small Engine Power Works. I have seen bad reviews about Power Mower Sales so I discounted them as a supplier. The part number I am looking for is 544874202. Most of the listings on the web have prices in the $40-$50 region with SEPW at a little over $10 plus $7 shipping. I thought I saw two in stock, but when I called SEPW they were out of stock, and needed to get it direct from Husky. My bad at the insufficient torque on the flywheel nut.
Pick out the broken pieces of the key and go get another from the hardware store. The flywheel should be OK
Dis-regard the above but you can still run it. Put it on with the original orientation and tighten it down. As long as the flywheel is where it belongs and the nut is torqued down good it will be good. The taper holds the flywheel not the key.
The keyway was part of the flywheel casting. If it were inserted into a slot I would have purchased a new key and been done with it. I am reluctant to tighten the flywheel onto the taper without the key and have it rotate and then be unable to remove it if it slips. I've gone this far rebuilding this saw to skimp on a new flywheel seems wrong. Unless someone on this forum has a flywheel I can purchase at a lower cost with reduced delivery time. SEPW's delivery time is just under two weeks.
Thanks
 
The key on the flywheel is to ensure it is correctly oriented & doesn't do much to stop it spinning. As rupedoggy stated, it's the torque of the nut & the tapered shaft that holds it. Removing some or all of the key to advance timing is a common mod & there are many saws out there running just fine without a key for the exact reason yours is missing... just need to make sure it lines up to where it should before you crank it up.
You can also file a notch where the key was & then make your own key to locate it.
Good opportunity to advance the timing a fraction too... 0.5mm / 0.020" would be a good starting point
 
The key on the flywheel is to ensure it is correctly oriented & doesn't do much to stop it spinning. As rupedoggy stated, it's the torque of the nut & the tapered shaft that holds it. Removing some or all of the key to advance timing is a common mod & there are many saws out there running just fine without a key for the exact reason yours is missing... just need to make sure it lines up to where it should before you crank it up.
You can also file a notch where the key was & then make your own key to locate it.
Good opportunity to advance the timing a fraction too... 0.5mm / 0.020" would be a good starting point
If I were to advance the timing, in which direction does the wheel turn? I'm thinking it should be CCW and when you state 0.020", that is on the outside diameter, correct?
 
I sorta mentioned this in a post on Arborsite a few weeks ago. (Then I was ridiculed by another person for mentioning it, decided to feel sorry for myself and go away.) It is VERY easy to get the wrong flywheel for a Husqvarna 440. There "are" (in some abstract sense) two "available" (depending upon which part list you look at. Yuh, particular "variation," but it is easy to get wrong). If I were you I would take the advice of the people who have posted above and use your existing key-less flywheel. (Put the piston at Top Dead, put little magic-marker marks on the outside edge of the flywheel at the -former- key "alignment orientation." Do it carefully and it will come together just fine -- with that little (little) bit of advance, unh hunh.) PS The "wrong" flywheel doesn't do well.
 
As requested. The flywheel spline is completely gone so filing a slot in the correct position, even installing it in the correct position might be a problem. In the second photo, there is a portion of the casting that looks like an indication of where the spline would be located. It looks like it is at the 9 o'clock position in the photo. Could that be correct? The name tag shows a 440e. The part number I selected, 544874202 I think is correct. Any thoughts?
If the tab is in the correct position, I am considering filing a slot to insert some kind of key to make it more like the original.
 

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Yes, if you mark both the fw and crank end, you can line them up. Gotta remove all of the broken key first. I also recommend using a piston stop such as a chunk of soft rope down the plug hole or spark plug style stopper to hold the crank in position.

Use only a wrench or socket and ratchet to tighten down the FW nut.... an impact tool may cause the FW to spin when the nut spins down. It happens!
 
You do you. However you want to do you. But...... were it I, I wouldn't file nothing, wouldn't cut no slot, wouldn't do no drastication of any kind, so "substitute" key. (At one point I did think of just drilling a little hole in ex-key-land and putting a tiny piece of stainless tig rod in it -- but then I laughed at myself for the thought.) Just do some rotational locating and marking. It is possible, maybe also using some helpful thing like a little metalworking t-square if you happen to have one, or simpler things, like a bit of fishing line, to make some very precise, very visible marks so that you can put the flywheel that you have exactly at the right rotational position on the tapered shaft, crank down the nut on the 8mm threaded part, verify that the flywheel didn't move -- and start the saw zappo doodah. a) I promise you. b) I have done it personally (and have lived to tell the tale...) c) if you'd like you can take advantage of a little timing advancing -- but I (for whatever it might be worth) make it just a little. Best start, even when cold, right amount of torq "gutsy-ness" etc.
 

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