New 42" Cut Husqvarna with a lot of Deck Vibration

[platefire]

Hello I'm Bob---new here! I've been doing more and more lawnmower mechanicing lately, so I thought I would join a forum that could help me along the way.

On my new Husqvarna I noticed that the deck was vibrating more than normal but seem to smooth out after mowing a while. Lately my wife has been using it to mow and she also spoke of the vibration. The only thing that comes to mind off hand is maybe the blades wasn't mounted right to match up with the star on one of the blades??? I've looked close at the top of the deck with the pulleys and everything seems ok there. I haven't pulled the blades to check them yet.

Any suggestions on what to check. I'll be diving into it here pretty quick and would like any shared knowledge on this I can get. I'll check the mounting of the blades and go from there. Thanks, Bob

 

[deminin]

Hello I'm Bob---new here! I've been doing more and more lawnmower mechanicing lately, so I thought I would join a forum that could help me along the way.

On my new Husqvarna I noticed that the deck was vibrating more than normal but seem to smooth out after mowing a while. Lately my wife has been using it to mow and she also spoke of the vibration. The only thing that comes to mind off hand is maybe the blades wasn't mounted right to match up with the star on one of the blades??? I've looked close at the top of the deck with the pulleys and everything seems ok there. I haven't pulled the blades to check them yet.

Any suggestions on what to check. I'll be diving into it here pretty quick and would like any shared knowledge on this I can get. I'll check the mounting of the blades and go from there. Thanks, Bob

Which Model is it???? Does the deck have 2 blades, or 3??? On some of the Husq decks...mostly the 3 blade decks...there is a belt idler pulley that can work loose, and start causing vibration....shortly before it throws/destroys the belt. The fix is pretty simple, but you have to remove the belt, and check for wobble, etc, on the pulleys to make sure this isn't the problem.

 

[platefire]

Hello! It's a YTH 1842 two blade deck. I'm a pretty decent lawn mower mechanic. I have inspected everything but the blade installation and haven't found anything wrong. All the idler pulleys and mandrel assemblies seem to be tight and smooth. I'm going to give it another going over before my next mowing and trying to lean something here at the forum to look for I may have missed. Bob

 

[bertsmobile1]

If it has the wavey mulching blades check they are no right way up.
Very common to see them fitted upside down which causes vibrations and the clippings to look sort of chewed up rather than cut.
That will cause vibrations that tend to calm down.
A belt that is too tight will also do the same thing.
If the blades are very low at the front you can also get vibrations particularly if it is caused by the mounting plate on the mower being bent.

 

[tom3]

I'd try a new belt, keep the old one as a spare.

 

[gotomow]

Since this is a new machine, have you contacted the dealer? Did you test drive this model before you purchased? If your particular one has more vibration then it's dealer time.

 

[platefire]

I'm in the process of mowing my yard right now, taking a break. Before I started I checked the blades then check all the pulley system on top of the deck. Everything looks jam up and jelly tight, just as it should be. In fact I cranked it up and engaged the deck before I inspected it and it was vibrating pretty bad.
After I inspected it, gassed it up and started mowing the deck has been operating very normal with minimal vibration. So right now everything is good. So I don't know??? I'll keep an eye on it and see how it goes. Thanks again for listening to my issues. Bob

 

[bertsmobile1]

Are all of the deck supports in place ?
Are they all intact with no cracks or loose bolts

Download your parts diagram from Husqvarna and check that they are all there.
I am faily sure you deck should have a stabilizer bar running across the rear of the deck, it may be missing.

 

[platefire]

Yes I have the downloaded parts manual but don't find a "Stabilized Bar" but does have "Sway Bar" on the exploded parts diagram. I will check the deck to see if that's in place---pretty sure it is?!?

One thing I was noticing browsing the pages of the parts manual it had a paragraph and picture about balancing your blade. I never considered balancing the blades??? The said with the blade off the mower, using a bolt through the center hold of blade hold the blade up and a perfectly balanced blade would remain horizontal but if the blade was unbalanced, one side would rotate downward---har! the old gravity method. They said the side that drifted down you would need to sharpen it more until it was balanced. I might give that a shot next time I sharpen my blades. Bob

 

[bertsmobile1]

Yes an unbalanced blade will cause the deck to shake, but the deck should continue to shake not smooth out.
It is the smoothing out that has every ones stumped
And yes , Sway bar , stabilized bar it is a tom-arto to-mato sort of thing.
On some models the two lift arms pivot on a bolt on bracket on the frame they can come loose or break which will shake the deck.
But that smoothing out thing ,,, weird.