RJR49 129 #1 Posted June 11, 2022 In another topic I described the sparkplug getting ejected from the head during prime grass growing season. Two professional cutting later, I realized that the tough grass wasn't the reason I had to make two passes to get a clean cut. I'm not running WOT which I'm sure is part of the problem. After all its a nearly 50 YO C-160. The bladed are sharp. New Gator blades, and the old ones to boot. I have long suspected that the belt is slipping. The tension is the original spring. I'm thinking that I need more. Any ideas would be appreciated- Share this post Link to post Share on other sites
stevasaurus 22,764 #2 Posted June 11, 2022 Your RPM's, gear you are mowing in, slipping belts, blades installed correctly and length of grass could all be contributing factors. You should be running at full or close to full throttle. If you are mowing in 3rd gear, try second. As far as belts, (for the mower deck only) wipe belts with Mineral Spirits then you could try a belt dressing. Important...Do not use belt dressing on your drive belt. 3 Share this post Link to post Share on other sites
peter lena 8,634 #3 Posted June 11, 2022 @RJR49 agree with Steve above on your rpm set up , 2nd gear is best for cutting efficiency and deck speed . only time I,VE seen hi gear gear cutting do well is on a perfectly maintained lawn set up , and regular weekly touch ups . would verify your mule bearing set up , smooth and easy spinning ? pto lever engagement smooth and solid ? how does the deck sound ? whining bearings ? travel speed and a not so fast deck , makes for a poor cutting finish . every rotational step has to be running with ease . probably hiding in plane site . pete 1 Share this post Link to post Share on other sites
RJR49 129 #4 Posted June 11, 2022 Its a hydro and I'm not going full speed. I'll check the rest. I'm wondering if anybody has any insight into a stronger.spring for the drive belt. I'm sure that after nearly 50 years this one doesn't have the umph it once did 3 Share this post Link to post Share on other sites
Ed Kennell 38,209 #5 Posted June 11, 2022 44 minutes ago, RJR49 said: stronger.spring for the drive belt. Are you talking about the belt connecting the three blade spindles. If you are, the blade covers should be removed and the belt and tensioning bar removed and cleaned so it slides freely in the guides. The spring is probably ok. 4 Share this post Link to post Share on other sites
RJR49 129 #6 Posted June 11, 2022 I do that at the beginning of each season. Now I'm wondering if something is worn and causing friction 1 Share this post Link to post Share on other sites
squonk 41,150 #7 Posted June 11, 2022 Just now, RJR49 said: I do that at the beginning of each season. Now I'm wondering if something is worn and causing friction Plastic guides for the tensioner bar do wear. 2 Share this post Link to post Share on other sites
Ed Kennell 38,209 #8 Posted June 11, 2022 Just now, RJR49 said: I do that at the beginning of each season. Now I'm wondering if something is worn and causing friction The tensioning bar and guides do take a beating. I've seen the guides and bar worn half way thru. 2 Share this post Link to post Share on other sites
killroy 35 #9 Posted June 12, 2022 Are your blades correct? I had same issue and found my blades were wrong. The ones I needed were exact opposite of what I had . You have to see what direction they spin and make sure it's the cutting edge not the back of the blade. Share this post Link to post Share on other sites
RJR49 129 #10 Posted June 12, 2022 Maybe that's the problem. I don't think there's any plastic bushing there The blades are correct. Hit a rock or two and its pretty obvious which side is cutting. Seriously, with the upturned edge of the blades doing the cutting I doubt there would be any clippings discharged Share this post Link to post Share on other sites
RJR49 129 #11 Posted July 27, 2023 Multiple problems. Mostly between my ears. Loose bolts on the clutch tensioner were a large part of the problem. But having the blades upside down didn't help. When I discovered that I was surprised it cut at all. 1 1 Share this post Link to post Share on other sites
dcrage 628 #12 Posted July 27, 2023 Isn’t it amazing how much grass the back of those blades can cut!! (And we worry about how sharp our blades are.) Yes I put my blades on upside down once upon a time. 1 Share this post Link to post Share on other sites
Lee1977 6,663 #13 Posted July 27, 2023 I don't know how worn your nylon belt tenture block are, but they only wear on one side. They can be turned around once. I did that many years back and wore out the other side. They have been NLA for years, I had a friend with a milling machine to machine the slots in some nylon block then drilled the holes and replaced mine. The bar I welded up the worn places and ground it back stright. My C-120 and that mower deck were not talking about acres mowed we are in the square miles by now. 2 Share this post Link to post Share on other sites
RJR49 129 #14 Posted July 27, 2023 I would like to see a picture of that Share this post Link to post Share on other sites
Lee1977 6,663 #15 Posted July 27, 2023 (edited) Not sure what you want to see. Here is a picture of the worn out blocks and the 1/2" x 3/4" nylon bar we made them out of. That was what was in the mower decks that came with the C-120 and the C-160. The later decks used a nylon bushing in a slot in the bar. Edited July 27, 2023 by Lee1977 Share this post Link to post Share on other sites
RJR49 129 #16 Posted July 27, 2023 I have a 1975 C-160, but the deck is off a C101 (I think). So, it maybe newer than the parts you show. Or, maybe older. I haven't seen anything nylon anywhere near the belt tensioner Share this post Link to post Share on other sites
Lee1977 6,663 #17 Posted July 28, 2023 2 hours ago, RJR49 said: I have a 1975 C-160, but the deck is off a C101 (I think). So, it maybe newer than the parts you show. Or, maybe older. I haven't seen anything nylon anywhere near the belt tensioner If it has the slots and bushing it's newer design. The deck mount was compeley different before 1973. Share this post Link to post Share on other sites
RJR49 129 #18 Posted July 28, 2023 I wish I had taken a picture when I was replacing the belt. It has a slot in a flat bar that the tensioning pullys is mounted on. But I don't see any bushings Share this post Link to post Share on other sites
Gasaholic 224 #19 Posted July 28, 2023 56 minutes ago, RJR49 said: I wish I had taken a picture when I was replacing the belt. It has a slot in a flat bar that the tensioning pullys is mounted on. But I don't see any bushings If it has 2 slots (about 1/2 inch wide) in 2 places in the flat bar and bolts & nuts that go through those slots, then there are 2-piece black nylon bushings on each bolt (or should be) You may have seen the fender washer that goes on top of the upper bushing - If your idler bar can flop side to side, your bushings are worn out and need replaced. Idler bar should only slide back and forth along the slots Other than that, the other style is as pictured further up - nylon shim on bottom and HDPE nylon slider bushings bolted in with 2 bolts either side of each bushing. 1 Share this post Link to post Share on other sites
RJR49 129 #20 Posted July 28, 2023 After all these years I would be surprised if the bushings aren't worn out. Shouldn't be a problem making new ones. I'm thinking that brass might be better. Either way making new ones is pretty simple Share this post Link to post Share on other sites
Rick3478 428 #21 Posted July 28, 2023 It's also possible to put the belt on the PTO backwards. I've never done that. Share this post Link to post Share on other sites