So I bought a reasonable newish greenfield mower on Marketplace. Greenfield 27 hp 34 inch fast cut about 3 months ago 160 hrs on clock. About 4 to 5 hrs in drive belt slipped and burnt. I believe this was caused by a twist in the belt. Anyway so long story short I replaced the drive belt thinking it might have just been an worn belt and i got another 2 hrs of mowing before the same thing happened.
Anyway two more belts later I realised what was going on and at idell the belt does not twist then as soon as you give it high revs the belt immediately on the left hand side of the idler pully as it goes onto the left hand drive pulley it twist which then if let run creates drive issues. Tried a new idler pulley but same thing, its not that so Im thinking of replacing the left hand drive pulley.
As the machine was not new when I purchased can anyone confirm that this idler pulley is meant to be a v pulley or flat. I cant see any other adjustment there. So apart from the big job or replacing the left drive pulley does anyone else have any other ideas.
Hi portabelly, welcome here. That pulley you are showing I assume is the pulley up under the seat where the drive belt changes the direction of the drive. Bit hard to see what pulley there but it should be a "V" pulley, flat idler pulleys run on the back side of the belt. I doubt this is the cause of your belt slipping and burning because the belts are designed to twist and flex in those short distances.
Norm, I don't think I explained it quite correctly. So what is happening is that the belt comes off the idler pully on the left hand side and it hits what they call I think the clutch pully. What is happening is that the belt will flip on its side on the left hand clutch pulley. So the belt will run on the side of the v over the left pulley instead of sitting in the belt in its v formation. When you put a brand new drive belt on and tension it up, you can start the mower and let it run at idel and the belt does not run on its side and runs normal. But as soon as you up the revs the belt will slip/flip back over onto its side on the left hand clutch pulley and continue in this manner all future rotations. unless you re tension and flip it back. It was doing my head in so I paid a very experienced mobile mower mechanic too look at it. He said he has never seen a greenfield do that before in 30 years. He didn't have time to change the clutch pulleys there and then but that was his suggestion for rectification.
Talking to an ex greenfield dealer he suggested I try and obtain an A134 Super 2 raw edge belt as a first shot before replacing the clutch pulley. However I did the ring around to about 10 belt places and no one could get one. So the project for the weekend is to replace the left hand clutch pulley and the idler pulley and hope and pray that fixes.
Bruce: in answer to your question its a 34 inch greenfield fast cut with the briggs and Stratton 27hp in it. I think its like 2017/2018 vintage.
Just replaced a with a new idler pulley. Does anyone have any recommendation's before i go ahead and replace the the left hand clutch pulley? I'm trying to avoid that as it looks like a mammoth job.
Just replaced a with a new idler pulley. Does anyone have any recommendation's before i go ahead and replace the the left hand clutch pulley? I'm trying to avoid that as it looks like a mammoth job.
Hmm Bruce, I think you might be onto something. I bought this mower with a flat idler pully installed and when I replaced it I asked an ex greenfield dealer for the part and that's what they gave me another flat. After doing a bit of research the part i need is a gt7965 according to the manual which is a v. However when I check my other 17 hp 32 inch fastcut it uses a flat pully as well.
Googling it shows both flat and v pulleys for the idler pulley so now im confused.
Ive given it to a repair mechanic to look sort out as Ive sunk 8 hrs into already but ill post what the outcome is within the next week.
There is no question about the pulley up under the seat, it must be a "V" pulley to keep the belt in its right plane, flat pulley encourages the belt to flip on its back. This is a problem caused by people not understanding what and how pulleys are designed to work
Hmm Bruce, I think you might be onto something. I bought this mower with a flat idler pully installed and when I replaced it I asked an ex greenfield dealer for the part and that's what they gave me another flat. After doing a bit of research the part i need is a gt7965 according to the manual which is a v. However when I check my other 17 hp 32 inch fastcut it uses a flat pully as well.
Googling it shows both flat and v pulleys for the idler pulley so now im confused.
Ive given it to a repair mechanic to look sort out as Ive sunk 8 hrs into already but ill post what the outcome is within the next week.
Ok So I ran out of time trying to fix this myself and dropped it off at a reputable mower mechanic. He swapped out with a v pulley and the mower now idels fine without the belt flipping. However after 10minuets of mowing the belt flipped onto its side. The belt was about 45 min old. Thinking that there might be some memory in the belt the mechanic then put in a brand new belt, however the same thing after 10 minutes of mowing the belt flips on its side.
The pully under seat has been changed to a V pully (this made some difference) The left drive pully got changed to a new one Has a brand new v belt.
Ok So I ran out of time trying to fix this myself and dropped it off at a reputable mower mechanic. He swapped out with a v pulley and the mower now idels fine without the belt flipping. However after 10minuets of mowing the belt flipped onto its side. The belt was about 45 min old. Thinking that there might be some memory in the belt the mechanic then put in a brand new belt, however the same thing after 10 minutes of mowing the belt flips on its side.
The pully under seat has been changed to a V pully (this made some difference) The left drive pully got changed to a new one Has a brand new v belt.
What else can be causing this and where to look?
Hi portabletelly,
What is the part number that they are using for the 'V'' pulley as is does not seem to be sitting correctly and appear to be running on the inside of the pulley.
Also brand and part number of the belt used.
Can you take a picture of the inside of the pulley so we can see if it is touching it?
Regards,
Bruce
Please do not PM me asking for support. Post on the forums as it helps all members not just the individual.
The v pully is part number 5937878-01 How ever the mechanic advised he had a 32 " fast cut with him and he tried the pully of that one it was a slightly bigger v pulley as well which would have been part number GT 7965 but it did the same thing The belt used is A3440 / A134
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