GT5000 and possible drive belt and/or transaxle problem
I have a new (to me) Craftsman GT5000 Model 917.276081. From the serial number I believe it is a 2004 model. It does not have the original engine. Instead, it has a new 26 hp B&S ELS with the updated air filter cover. It is a hydrostatic shift instead of manual shift.
I have owned this mower for about 6 months now and up until a couple of weeks ago, I've had no problems. Whenever you first start cutting, the mower does fine. It has no problems going forward or reverse, although the reverse seems really slow compared to my previous MTD mower. After about 20-30 minutes of cutting (with temperatures in the mid-80s F), reverse gets really slow, but forward speeds only diminish very slightly with a very slight and brief growl when going into the upper range of the forward speeds. After another 15 minutes, the reverse is gone and when going forward, the growl gets a little louder and I have to push the lever forward more than usual to reach my desired speed. At this point I did touch the transaxle housing and it was very warm, but not 'burn your hand' type hot. The cooling fan on top of the transaxle is intact and does have all of it's fins. There was also some "play" in the drive belt at this time. I did not measure the amount of play, but I estimate at least 1 1/2". I also tried the suggested method of purging the transmission of air on page 14 and 15 of the owner's manual and this did not seem to help.
If I shut the mower down and let it sit for roughly 45 minutes to an hour, I can fire it up again and the forward/reverse is much better, although not as good as it should be.
I suspect the problem is either with the drive belt, pulley or possibly the transaxle. To my knowledge, the drive belt has never been replaced.
Any help would be greatly appreciated.