Husqvarna will crank but won't Start.

Joed756

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Hey Joed756, so I started to dig into the motor and found some major items wrong. First, I have to go get a flywheel puller to check/replace the flywheel key. In the meantime, I took a number two pencil to make sure the pistons were moving, and they are. But I thought I would pull the valve covers and found a bent rod on the left side facing the motor and on the right side neither rods are moving. How bad is this?
 

Joed756

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I believe your son hit something and caused the flywheel key to break, the engine turning over out of time caused the push rods to bend. It's not the eng of the world, but hopefully that's the extent of the problem. Check youtube for some how-to videos. You can use a soft faced mallet to tap on the flywheel while turning it by hand and it should pop loose. Otherwise auto parts stores will let you borrow a puller.
 

sam1967

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I believe your son hit something and caused the flywheel key to break, the engine turning over out of time caused the push rods to bend. It's not the eng of the world, but hopefully that's the extent of the problem. Check youtube for some how-to videos. You can use a soft faced mallet to tap on the flywheel while turning it by hand and it should pop loose. Otherwise auto parts stores will let you borrow a puller.
I think your right about hitting something. I think the most trouble thing is the steel push rod for the exhaust on left side isn't there anymore. I can't see any metal in the head/cylinder, nothing. I'm thinking there might be more damage now that I couldn't find it. Have you ever heard of a push rod going back into the piston cylinder?
 

sidemouse

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Ok this is off a valve cover. Model #44N877, Type 0003G1, code 160810YG

That is a Briggs & Stratton.
More than likely from what I am reading you do have a problem with the push rod having bent / falling out of place. This is a fairly well documented issue, usually the reason is overheated engine. The cheap repair is to buy all new pushrods and not sure if this engine has guides but if it does then those too... Reinstall everything, properly adjust the valves, put it back together and then clean all the cooling fins and everything around the engine of accumulated dirt and grime (as this is what may have led to overheating in the first place), and last but not least hope that took care of it.
 

grumpyunk

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You can use a magnet to poke around down the channel where the missing pushrod used to be. Use a flash light and magnet to see if you can find the pushrod. If left internal, it can damage the other parts such as cam gear, governor, and more. If they are not already damaged.
The pushrod likely bent when the rocker arm ran into the top of the valve guide. Unless the valve seized in the guide and would not move, the only other thing that comes to mind to stop the rocker arm from moving is the top of the valve guide. The guides are pressed into the cylinder head. If the head gets too hot, the guides can migrate upward and finally move enough that they collide with the rocker.
You may(should) remove the blower shroud covering the engine & flywheel. It may be that you have a good accumulation of grass clippings, or even a mouse house that are blocking airflow over the finned area of the engine. Without the cooling airflow, the parts get hot and move around in an uncontrolled manner. Damage ensues.
You can compare valve guide height by measuring the distance from the top of the cylinder head(base of the valve spring) to the top of the guide. As a general rule, they should all be the same. If one is higher than the others, it has moved and is likely the cause of the bent push rod. Replacing with a new push rod will NOT fix the problem if the guide has moved, it will just re-occur almost instantly.
So, remove and clear the cooling, check guide height, and if the guides have moved, repair. There are articles and likely YT videos that explain how to push the guide to its proper location, add some Loctite before doing so and finally use a punch to 'stake\ the guide in place. Many report long term success by doing this.
You will have to remove the head to push the guides back as the valve(s) must be removed prior.
tom
 

Goby1234

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Husqvarna YTA 24v/48 Body Product #960450052, Serial #032717A040676 Serial # on engine is 16 0810 YG 30268
My son was mowing a few days ago and ran out of gas. He filled up the tank with no more than a week-old gas and continue to mow for an hour until the mower died. Mower cranks but won't start even which starting fluid. Check the solenoid below fuel bowl it clicks while turning key. I also took it apart and verify it move with key. I sprayed with WD-40 and reinstalled. Took hose off at fuel filter made sure no air, took fuel hose off at fuel pump turned key lots of fuel pumps out. Took both spark plugs off and tested against block of engine both had good spark. I will be trying to locate a combustion tester tomorrow. I will say while cranking the motor it doesn't appear to me the motor is even close to starting.

Thanks in advance for any responses.
Fuel, spark,or air. check the choke linkage and air filter. Also check the fuel hose at the carburetor for fuel. Could be a weak fuel pump. This exact same thing happened to me. Was running fine, then ran out of gas and didn’t want to start. The pipe going from carburetor to fuel pump had vapor lock. It was a weak fuel pump, even though everybody told me it couldn’t possibly be that
 
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biggertv

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While Keyway could be bad, it's unlikely. This is a Riding Mower and Keyway is buffered by a belt that will slip. Sounds like a plastic cam got damaged.
 
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