I'm glad you were able to get it working.
If you purchased the trimmer new it comes with a 2 year warranty. There could be several different reasons the trimmer won't start. I would suggest taking it back to the dealer and have him check to see if it would be something covered under the warranty.
There is also a mulch kit that you can purchase from Husqvarna. The part number for the kit is 531 30 95-80, model HU46. MSRP for the kit is $49.95. The kit includes the 2 mulching blades as well as the deck plug.
Since Kohler is the manufacturer of the engine it would make sense that you would need to get the information from them instead of Husqvarna. When you purchased the mower it should have come with an owners manual for both the mower and the engine. If your mower didn't come with both I'd contact the dealer and have him send you one.
There is an adjustment that can be made on the cable but it's a little hard to explain in this forum. Your local dealer should be able to fix that pretty easily.
The problem with it not shutting off could very easily be just an adjustment with the cable.
As far as the blades not engaging it sounds like it could be a cable issue as well. Do you have a local dealer you can take it to? The mower comes with a 3 year warranty that should cover any problems.
The main difference is the HU700L is a rear wheel drive mower and the HU700F is front wheel drive.
It indicates a wrap handle. Check out the picture attached.
Here is a link to the owners manual. You can find the manual as well as a parts diagram on Husqvarna.com. Hopefully this helps.
/images/ddoc/HUSO/HUSO2010_USen/HUSO2010_USen__115384327.pdf
Depending on how long the machine sat in Husqvarna's warehouse and when the dealer ordered it, it could be several months after it's manufactured before the dealer gets it. But that doesn't mean the machine isn't new. If it's never been ran then it's still considered new. The warranty will go off the purchase date as long as it is registered with that date.
This is very common with most self-propelled lawn mowers, no matter the manufacturer. If you let go of the drive levers and push the mower slightly forward it will disengage the gears in the wheels and allow you to push it freely.
It is sold as one piece. Depending on when you bought it, it's possible it would be covered under a warranty. But you would need to take it to a certified servicing dealer to know for sure.
The other thing that you should check is the shaft where the blade attaches. It is very common that the shaft gets bent when you hit something that bends the blade. If the mower shaft was bent, your mower will probably shake while running and it can be unsafe to run the mower. The vibrations can cause the bolt on the blade to loosen, which can be very dangerous.
I would recommend having someone check the shaft on your mower to make sure it isn't bent.
The spark plug is a Champion RC12YC. You should be able to find it at any auto parts store, like O'reilly's. I believe the size of the socket for that plug is 5/8".