Mick,
To try to help you out, check the blades as the others suggested, but my guess is if your having problems with Dandelions its probably because the lawn is in real poor shape. We have a lawn like that and although you cut most of em, a bunch just pop back up and laugh at ya. If thats the case you need to tell the client to treat the problem not the symptom and get some fertilzer and weed control on that lawn.
Now for the real reason for my post.
EJK,
Let me commend you on your absolutely worthless post. Why is Exmark the best??? Cause thats what you bought? What other ZTRs do you have extended experience with??? Have you plunked down the hard green for a TORO and found out it didnt work???? Im sick of useless posts like yours that provide no benefit to the new guy asking the question. I wonder how many of your other 535 posts have any real value.
What if his closest exmark dealer is 400 miles away? Have you helped him with your comment? NO. Have you made any suggestion at all, like the others here have, that perhaps its the blades or some other problem. NO!!!! Have you in any way added useful piece of information to answer this guys question? NO!!!!!!
All you've done is thumped on your chest and said "I BOUGHT AN EXMARK SO IT MUST BE THE BEST"
Thank you very little.