Uneven mowing is a bigger subject than most people are willing to even consider. Most people really just ignore it. In a few days the uneven cut is less noticeable due to additional growth. Like you, I noticed the problem. Over quite a few years I have worked on the problem. In your particular instance the problem may be in the mower design itself. Such is the case on most riding mowers. Your deck is leveled like you said and blades are new. Here's some additional things that you can check. Check all blade heights to the (Level) concrete drive at front, rear, right, and left. Another big factor is deck wheels. Any deck wheels should be adjusted 1/2 inch from touching the concrete when the deck is set to your mowing level. Most people do not do this. I even added front deck wheels on several mowers that did not come with them and it evened the cut a lot. Also be sure all four tires are inflated fully and are all the same. With leveled blades and four deck wheels adjusted 1/2 inch from the ground any deck should give a reasonably good level cut. Keep in mind that a lawn that isn't flat cannot be cut "level" with a mower that cuts in a flat "plane". Golf courses use expensive $50,000 reel mowers that cut almost perfectly and leave almost no uneven areas.

Generally you are lucky to get close to 4" height of cut on these- usually closer to 3 1/2" . By striped, you are speaking of leaving a center strip? Is the deck kept clean?

my blades are cutting different heights. leaves my yard striped I don't have a manual for it because I bought it used. How do you level it out?

Can you tell if one of the blades is not cutting flat?

If the individual blades are cutting flat but at different heights then the mower should go back to the repair shop to be corrected. You paid for the service.

sounds like you have a bent blade, take the blades off and stack them on top of each other, they should nest perfectly if they aren't bent. another thing it could be is the blades are wrong for the mower. they are the correct length, but the cutting edge is lower than the correct blade. if they are digging into the turf, I wonder if you have high lift blades and one is on upside down.

I am late to this thread, but I have the same problem. I replaced the blades and spindles (thinking my teenager bent either or both), but the problem is still there. It's almost like the blade on the chute side isn't spinning fast enough.

Maybe a broken deck pin. Or a missing deck pin. I think you have 4 of them.

Well it takes some checking on your part to level deck. With the blades mounted, turn them by hand (engine off) and note where the blade tips align on the deck. I use a good sheet of plywood to position the mower on as it is more level than most concrete. Take a 3 ft. pc of 1 X 2, run a screw into it which you can run up and down so blade tip just touches the screw head when slid under blade ends. Your deck may be bent where mandrels mount. IF everything seems OK but one blade is higher than the other, use spacers to even height. I find a better cut with the blades 1/2 inch or so higher at the rear than the front. How to adjust? I don't know your mower, turn screws, bend arms, use a big hammer, etc. I have done all of these.

Walt Conner