chalky 4 #1 Posted August 2 Got a 1977 B80 in mint condition , when I mow in the high side .I mow in second gear after a while feels like the mower speed slows down. Got all new belts deck and drive gear belt..And I don"start drinking until I'm done . Any ideals ? Thanks . 2 Share this post Link to post Share on other sites
oliver2-44 9,847 #2 Posted August 2 Being a gear here's a few things to check. 1. The drive idler could effect belt slippage, so check that the drive idler pulley bearings are good, idler spring is working and not stretched out, oil the idler pivot points to insure free/smooth movement of the idler arm. you have to remove the belt guard to do this. I would put it up on jack stands to test running it and looking for belt slippage. Just a reminder, the gears in these transmissions are not synchronized so they will not shift smooth (gears grind) shift if the belt is turning the transmission. The belt guard helps to "slack the belt to help it stop moving" when you step on the clutch. 2. Check that the engine and transmission pulley keys are in place and mounting set screws are tight so pulleys are not slipping. you can do this by marling a line across the end of the shaft/pulley to help you see if pulley is loose. 3. Check that the axle hub is not slipping on the shaft and the hub locking bolts are tight. just like the pulleys, mark a line across the end of the axle/hub to took for slippage (tractor tires need to be on the ground for this test. 4. If all of this checks out, start drinking while mowing and you won't notice the slowing down. 4 3 Share this post Link to post Share on other sites
peter lena 8,716 #3 Posted August 2 @chalky how about 3 rd gear , low range ? that would give you a gearing advantage , in easier movement , agree with @oliver2-44 on the related pulleys , very often there are related drive issues , due to incremental pulley hang ups , related linkage , connection / function . another thing is deck discharge , sounds like its loading up , cutting on highest setting ? what does cut grass look like ? heavy pile up , clumping ? whenever I cut , always look for effect of discharge , and adjust as needed , think its a 2 stage issue , too much speed , and inefficient related deck drive , pete Share this post Link to post Share on other sites
ri702bill 8,479 #4 Posted August 2 29 minutes ago, peter lena said: 3 rd gear , low range Pete has a piont - 3Lo is faster than 1HI, but a bit slower than 2Hi. A question - does the B80 have the older friction lock throttle like my 854?? Mine does relax a bit and slow down after a few minutes in. Some folks use a snappy clothespin on the throttle... Even the later lever style can slip & relax if not set properly... 1 Share this post Link to post Share on other sites
Handy Don 12,436 #5 Posted August 2 1 hour ago, ri702bill said: Mine does relax a bit What a lovely way to phrase it! Share this post Link to post Share on other sites
ri702bill 8,479 #6 Posted August 2 20 minutes ago, Handy Don said: What a lovely way to phrase it! Share this post Link to post Share on other sites
Pullstart 63,080 #7 Posted August 3 18 hours ago, ri702bill said: 3Lo is faster than 1HI, but a bit slower than 2Hi. Somewhere there is a chart. I feel like 3lo is still a tiny bit slower than 1hi based on my butt dyno experiences but I can’t find that dang chart. Share this post Link to post Share on other sites
Handy Don 12,436 #8 Posted August 3 (edited) 13 minutes ago, Pullstart said: Somewhere there is a chart. I feel like 3lo is still a tiny bit slower than 1hi based on my butt dyno experiences but I can’t find that dang chart. This is for 8-speeds but the 6-speeds are the same. 3rd low is still slower that 1st high by quite a bit. Th high/low is a factor of 4 ratio. Edited August 3 by Handy Don 1 Share this post Link to post Share on other sites
