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It's getting that time of year here in the south. The weeds are popping up and things are growing slowly. Last year I grenaded the 11hp briggs on my beloved snapper sr930. I found this craftsman on craigs list for $200. Needed a muffler which was easy enough. Didn't put the oil dipstick back in right a couple of months later and popped a valve when it blew oil out of the crank case. Fixed that and all's been good. Toward the end of last years cutting season I noticed an odd cutting pattern. It seems to leave a two to four inch strip of grass that isn't cut in the middle after new belts and blades and the blades are the right part number for the mower. Deck spindles with new bearings are cheap enough around $50 on ebay or amazon and honestly are the only thing that hasn't been replaced on the deck. Oh well order placed I hope this improves the cut pattern when it's put back together and the deck leveled.

The blades are wrong or on upside down.
That is an AYP ( Husqvarna ) mower with a very shallow deck which is sensitive to blades.
When fitted the blades should miss each other by about 1/16".

Original pattern aftermarket blade work quite well but third party blades like Gaitors dont because the deck is way too shallow.
If you have the 3 point mounts on the spindle housings take extra care to keep the vent holes around the housings clear .
And if you are fitting cheap Chinese bearings expect to replace the entire housing if not the deck within a season or two.

The most faked item , by volume is bearings and most of what is offered on the web is Chinese or Indian trash.
If you must buy bearings on line, check that the "shop" is real, had a phone number and a pick up address then google the address and check what is there.
Most of the internet bearing companies do not exist they are just web pages created with stock images & photoshop.
bearings come in from China to a 3rd party warehouse who gets dispatch orders from the web.

Blades are the right ones factory part from the local shop and on right because it cuts perfectly except for that little strip and the top of the blades were marked up. They are close and do look tike they would touch. I'll keep an eye on the vent holes this season didn't think about that last year, might be the problem. I'm going to pull a spindle and go to my bearing supply house to see about replacements seeing as how the spindle housings are undamaged. If not I do have a couple of parts suppliers that carry a wide variety of factory parts all within an hours drive or less from me. I'm going out now to look at the vent holes in the deck and look over the rest I'll be doing my first cut of the year tomorrow. Still will need the bearings though the right one is getting noisy. Thanks for the help I didn't take the shallow deck into consideration. I found a cheap rebuilt briggs at a shop on the way to the bearing supply if that works out I'm going back to my SR930. I lose a foot of cutting path but that rear engine beast cuts great at any speed and will run circles around the big craftsman.

Whenever I do anything with the deck, blades or whatever, last thing I check is carefully rotating the blades & at the center check to see that the blade tips line up on height & small gap, then spin both 180* & check again.

when I got this thing it was kind of rough. Rotted off muffler and tired deck belt. It cut well when I replaced the muffler and I always cleaned it well after use. I bent a blade one day and got replacements at the mower shop. They have some n.o.s parts at times and had the factory blades cheap enough. Just thought of another problem that might be contributing to the odd cut besides the deck vent which one was partially clogged. I cut with the deck at it's highest point. Texas summers are hard on lawns so I try to keep it long during the dog days. Shallow deck+ clogged deck+ max cut height might be my whole problem.

I always measure replacement blades. You never know. On my Toro 42" two blade, each blade measures 21.5" x 2 = 43" (Go figure).

I'm in the process of rebuilding a 38" deck and noticed that there is about 1/2" of play in each mounting hole where spindles go in. So, if you mount the spindles to the extreme "far apart" that's an inch. Plus (+/-) 1/4" for the clearance between blades as per design. Now, what type of a blade did you put on? No-lift, standard lift, high lift, mulch? Hi-lift blades "pull" grass in under the cut eliminating uncut "dead zone"...another thing I wanna say is that with pressed decks I'm a firm believer in deck/spindle reinforcement ring. Its a 1/4" steel ring with mounting holes that goes under the deck, mounting bolts go thru the ring, deck and into the spindle mounting bracket reinforcing and stiffen it all up. Goes for about $10. And the reason I'm saying this is because you stated that the uncut - dead zone - varies from 2" to 4" making me think that there is some deck flexing going on as well.

As far as replacement bearings I only buy NTN or Timken / Fafnir brand. Unfortunately...they're both made in Taiwan!!!

The blades I got were nos craftsman in the package with the correct p.n. Same length as the ones I took off but did notice differences in tractor supply blades by brand. I used standard blades. My deck's been reinforced by the previous owner the variation comes from the mix I cut between grass and weed that's a lot tougher to cut. As stated earlier in the post the deck is shallow compared to my old Snapper by at least 2 inches. The vent holes in the deck were indeed plugged more on the right though. I cleaned it out good and am heading out to pick up some new bearings. My supply house has Timken been using them for years so I'm good with that.

Each blade has to overlap the other to get a complete cut.
To do this either then blades have to be timed so they don not hit each other or the spindles must be off set front back or they will hit each other.

You notice this most when you turn,
Turn one direction will leave a mowhawk in the grass while turning the other way will not leave a mowhawk but will make a narrower cut.

When cutting at full height you get the least amount of airflow under the deck to make the grass blades stand up so they can get cut off.
To compensate for this you have to drive slower.
This effect will be different for different types of grass.
Also if the bade speed is too slow this will also happen.
The mower must be running flat out when cutting.
A lot of people run at 1/2 speed because they wan to move slowly so the airflow under the deck is further compromised and the blades are spinning so slow the grass just bends over.

bertsmobile1 said:

Each blade has to overlap the other to get a complete cut.
To do this either then blades have to be timed so they don not hit each other or the spindles must be off set front back or they will hit each other.

Click to expand...

Bert- I never have heard of overlapping blades. You can't keep belt driven blades in time. No sorry, that's not right. There is a 1/8" gap between my 2 blade Zero, which is how I check then for running true etc.

7394 said:

Bert- I never have heard of overlapping blades. You can't keep belt driven blades in time. No sorry, that's not right. There is a 1/8" gap between my 2 blade Zero, which is how I check then for running true etc.

Click to expand...

Your ZTR may not have timed blades, but that doesn't make it impossible. Cub Cadet and John Deere have been using timed decks for several years and I believe Toro used them on a few models as well. They used a toothed belt to keep the blades in time.

I wouldn't want to own one though!

...And it makes me wonder why don't they use a motorcycle style chain driven spindles?

Several reasons I can think of:

-Mower decks are exposed to lots of sand. When you have a rubber belt on metal pulleys, sand will wear both, but the belt will take most of the wear. With a metal chain on metal sprockets, the sand would wear both your sprocket and chain evenly, forcing you to replace both.

-A rubber belt can stretch under stress when the blades are engaged. A metal chain will stretch as well, but it will stay stretched.

-Chain and sprockets are probably more expensive than belt and pulleys.

-A chain driven deck would be VERY noisy.

-A toothed belt will slip, break or jump teeth if you hit something. Sure, the blades may hit each other, but at least the engine has good chances of surviving undamaged. If you hit something with a chain driven deck, you will break your chain, maybe your sprockets, and you might bend your crankshaft as well.

-You would need a fixed deck in order for chain drive to work. With a chain setup, your sprockets have to be in line (or close to in line) with each other.

I've meant double belt deck design. One belt is just for the spindles and doesn't go up or down and the other one (off the double pulley) goes to PTO. So, replace the "stationary" belt and pulleys with chain and sprockets, cover it all up with plastic or metal cover (no dust gets in) poke a hole so that the shaft could go up thru the cover and install a regular belt pulley there from which a belt goes to a PTO.

The subject of blade off set on a 2 blade mower decks makes one think, how many people use one all of their lives wondering why their tractor deck doesn't set 90° to the tractor and direction of travel.:laughing:

Ahhh...to H E L L with all them decks!!! I just wish that Harley Davidson make mowers!!!

Jack17 said:

Ahhh...to H E L L with all them decks!!! I just wish that Harley Davidson make mowers!!!

Click to expand...

So do I
They would have never changed for 50 years which would make fixing them really easy :laughing::laughing::laughing:

7394 said:

Bert- I never have heard of overlapping blades. You can't keep belt driven blades in time. No sorry, that's not right. There is a 1/8" gap between my 2 blade Zero, which is how I check then for running true etc.

Click to expand...

Either I have not expressed myself clearly enough or you have not understood what was posted.
If you check the length of the blades on a 42" deck they will be somewhere between 21.25" to 22" long.
Now if your cut is 42" and the total blade length is between 42.5" & 44" then the blades must overlap.
In fact this is shown in all the owners manuals.
One blade is offset foreward so as you drive foreward the back blade overlaps the area already cut by the front blade.
THIS IS OVERLAP AND EVERY MULTI BLADE DECK HAS IT,

Stand on your mower and look directly down at your deck you will see one side ( usually left ) is further forward than the other side.

AS for timed blades, been around from the very beginning of multiblade decks.
Uses a timed belt with teeth, like on the cam shaft of your car, and pulleys with teeth .
The Husqvarna Rider Pro range which gives a cut quality equivalent to a drum mower all have timed blades with each blade at 90 deg to its neighbour.
The Stiga ZTR also has the same system and the Stiga articulated mowers both came with optional timed blades.

Timed blades are not particularly popular with most USA owners because of their obsession with lego land (striped ) lawns

And that's because every "good" lawn in America should look just like a Football Field on Super Bowl Sunday. If I could come up with a little robotic spray painting machine that would link up with your smart phone and paint using eco-friendly paint different team logos and signs on their lawns I'd be a Millionaire! :thumbsup:

7394 said:

Bert- I never have heard of overlapping blades. You can't keep belt driven blades in time. No sorry, that's not right. There is a 1/8" gap between my 2 blade Zero, which is how I check then for running true etc.

Click to expand...

Possibly this pic will explain how overlap is accomplished without the non timed blades beating themselves to death.

SeniorCitizen- Thank You, Yes I understand that & my current Z & the many, many tractors before this have had that exact set-up. Yes they overlap in fore & aft rotation, but could NEVER hit each other.

As to the "Timed" cog belts, that is something I have never encountered. And I'm never too old to learn something new. So to Bert, Sir, I stand corrected, & learned something new.

Thanks All. :thumbsup:

You're not alone, we all learn new things every day. :smile:

In my opinion, timed decks are a bad idea because of the safety issues they present. I'll stick with my standard deck ZTR. :thumbsup:

primerbulb120 said:

You're not alone, we all learn new things every day. :smile:

Click to expand...

True, I seem to remember best the things that I have to first remove my foot from my mouth tho. :wink:

One of the important reason for teaching science is the way science treats FACTS
A fact is something that can be substaintaed by others and remains so till it is proved to be wrong.

Where as in economics , a fact is something that you manipulate the evidence to maintain its validity.

And yes the stronger you defend your misconseptions the more you will remember when you are proved to be wrong.

The day we stop learning is the day when all of our friends stand in a circle and throw handfulls of dirt on our coffin.

Well stated Bert.

Just a quick update to my original post. Kinda went left for a few pages. I got a set of timkens from my local bearing supply so the deck is a lot quieter now. While the deck was off it got a thorough inspection and cleaning. Everything moves as it should on the deck now. The pulleys show some wear but not out of of tolerance yet. Reinstalled the reinforcement rings on the spindles no cracks on the mounting holes both deck or rings. I made sure the vents were clear and started the old dog up to begin the season. All I had to cut were a lot of weed so far but it was even and no uncut strip. Looking back to the beginning of this issue it seems the vents in the deck were clogged and not creating the proper vacuum on the shallow deck. The deck on my Snapper is over 2 inches deeper than the craftsman and the neighbors Deere is at least an inch or more. As the grass comes in and the weed in the back 40 I'll lower the deck a click or two and slow down a bit. Should have the problem cured plus keeping the deck cleaned after every cut. My parts for the 11hp briggs should be here next week so I'll have my Snapper up and running might just sell the craftsman after that and invest in the rest of the small stuff for the sr930.

Very nice! Job well done!:thumbsup: