Mowing 48" Deck trouble cutting

[rebmo]

I have a 92 JD GT262 in overall good condition and need some tips on cutting with the 48" deck. The GT has a 17hp Kawa and gets around fine but I have some problems cutting this Spring. My yard is 1.1 acres and mostly grass with 2 hills either side of the house for exposed basement. I've used the JD since late summer last year until now and had some problems this spring. I should point out that I live near sod farms and my grass grows like I have a sod farm in the back 3/4. If I dig down a foot it's all black peat due to living where a swamp once was and a dam and channel now handle the water. So I have this super thick lush green grass, nice to look at, tough to cut.

All was fine last August into spring. Dry summer had the grass dormant for the most part and fall was pretty dry too. So only a few times I had difficulty cutting a few areas where it gets super thick. I slow down and that helps.

But, this year in spring, I cut once per week and it's usually about 4 to 4.5". My deck starts vibrating at times and I slow down to almost the lowest speed and it doesn't help. I get smoke from the belts at times. I try cutting a smaller swipe of uncut and still get the deck stalling. It's clean, it's greased and spins freely. I did replace the PTO belt. Still have a hard time cutting where it get's really thick.

I'm new at "large lawn" cutting and Garden Tractors, so looking for advice for things to check. Deck Belt? Bearings, ???? I have the cut height at 3" now. Not sure what to try next. I can seem to cut the front (sandy soil)what I would call normal grass without issue, just the back 3/4 which gets super thick. Maybe I need more HP or machine, but wow, I see some of my other neighbors with simpicity yard tractors and they do pretty good, but My grass is open sun and theirs is shaded somewhat so probably not as thick.

Suggestions appreciated,

Reb

 

[kthompson]

Don't know your mower but sounds as it has gears. If so do begin with slower speed rather than drop to it. But have you checked the blades? Did not see any mention of them. Have you replaced them, they probably need to be if not. Also be 100% certain you have correct blades and installed properly. On some mowers they are easy to install upside down causing the non cutting edge to try doing the cutting.

Also if you are getting big wad of grass under the deck you may not be allowing it to kick out and thus causing the belts to smoke and not catch back up.

You are running engine at full rpms? It is running at full rpms since sitting for the winter? The rpms are needed for blade speed not moving speed.

Depending where in the South (my guess based upon some comments) you are the thicker grass may need to be cut even every 3 or 4 days. With rain and type of grass.

How is your air filter? How about tires air pressure?

 

[rebmo]

First, thanks for all the good things to check,

The JD 262 has gears (6 speeds clutch). I do start slower but the lawn thickness does vary so I drop in speed prior to thick spots. I live in Wisconsin, south rural. Mostly Kentucky Blue grass. The blades are installed correctly and sharpened/balanced. They cut real clean in medium to low density areas. The deck bottom is clean and oil coated so not much sticks. Engine seems to be at top RPMs, I'll have to double check the air filter an blow it out for now just to see if that has an impact but it should be good, and RPMs seem up there. I will veryify.

Unfortunately, I may just need to cut twice a week to get through this. It hasn't been too wet, but there's been adequate spring rain for good growth. Tire pressure is all at correct spec settings.

I may just have to get out and cut tomorrow or Friday having cut last saturday. Folks can't believe how thick and lush the grass is in my back yard. I guess it's a good/bad problem.

I'll try the tips I haven't checked and report back. Thanks again for the ideas.

Reb

Don't know your mower but sounds as it has gears. If so do begin with slower speed rather than drop to it. But have you checked the blades? Did not see any mention of them. Have you replaced them, they probably need to be if not. Also be 100% certain you have correct blades and installed properly. On some mowers they are easy to install upside down causing the non cutting edge to try doing the cutting.

Also if you are getting big wad of grass under the deck you may not be allowing it to kick out and thus causing the belts to smoke and not catch back up.

You are running engine at full rpms? It is running at full rpms since sitting for the winter? The rpms are needed for blade speed not moving speed.

Depending where in the South (my guess based upon some comments) you are the thicker grass may need to be cut even every 3 or 4 days. With rain and type of grass.

How is your air filter? How about tires air pressure?

 

[uglyboywith11fingers]

But, this year in spring, I cut once per week and it's usually about 4 to 4.5". I have the cut height at 3" now.
Reb

do I read right... this thick grass is 4 to 4.5" high when you cut it down to 3"?
that must be some tough grass you've got. My grass over the weeping bed area grows fast & thick, and I do need to slow down there with my Kubota TG1860G (18HP Kawasaki) and 54" deck. This grass is usually 6" or more high when I cut it to 3.5", but I certainly don't experience anything like you describe.
If you've checked your blades, etc. I don't know what else to suggest... if you had more HP, you'd just smoke the belt faster. Maybe a problem with the belt(s)... not enough tension ? have you verified that you have the correct length belt ?

Pete

 

[jcdogfish]

I had a gt 275 years ago. I am not familiar with your type of grass but my experience is that deck does not like clover. Any thick damp kind of grass is very difficult for it to kick out. You can check the deck bearings to see if they are getting hard to turn which eats up some of the hp and make sure the fuel filter and carb is clean which makes it bog easily. Other than that, take small bites, always exhaust the grass away from your next cut and either make 2 passes or cut more often. Or get a mower with a commercial deck and more hp.

 

[rebmo]

Yeah, the grass is really super thick Kentuck Blue, and no clover. When I get into the really thick grass the motor does not seem to drop in RPM but the deck stops or a few times I smoked a belt just a bit before I stopped quickly and backed off. I can sometimes see where the grass stops getting cut behind and I have to stop, back up, and start in even slower.

So I had put a new PTO drive belt on. The one the tractor came with was coming apart early this spring, so a new one is on. It is a size matched to the old one from the hardware store. Does a OEM JD belt do a better job gripping? The old belt did the same thing early this spring but can't say it was OEM. I have not checked the deck drive belt or the spindles individually, but have greased them and the the blades spin pretty easy with the deck off.

Any suggestions on belts? JD OEM? Hardware Store (Rural supply HW)? I haven't checked or changed the deck blade drive belt so that will happen when I get the deck off.

And yeah, I'm not taking much off and when I get into the thick stuff the blades stop. For most of the yard I'm gettting a nice clean cut at pretty good speed but the 30% that's really thick is shutting down the deck.

I will check the fuel filter and other suggested items. I'll post on what I find. BTW I also have a backup 1978 Allis Chalmers 718 GT and it bogs down even quicker. (Same as Simplicity). I need to sharpen the blades on that machine though. Pretty comparible power wise so it may just be the grass and seasonal conditions.

 

[jcdogfish]

If it is not bogging the engine and smoking the belt I would look at putting an oem belt on it. I have stalled the 275 and not have the belt slip. If it is throwing the grass out of the discharge and not just pushing it out in lumps I would go with a good drive belt. If its not bogging the engine your filters etc are probably fine.

 

[kthompson]

With your additional info totally agree with the last post. It is not engine so forget filters and such. That was when thought the engine was bogging down.

Do have a couple of recommnedations on the belts: do get OEM, look to see for certain which belt is slipping and also be sure oil is not leaking on to the drive pulley on engine nor you getting grease on pulleys on deck.

We installed new engine on a snapper once that did this and it had OEM belt and would smoke till it burnt the belt. With the little stronger engine had to run the drive belt on the tight side of specs to prevent any slip.

Most likely you can get dealership to ship belt to you.

 

[taborekle]

I have a JD 425 and have seen where if I mow to much to fast, the deck will vibrate, stall and eventually clog. I believe it's because the deck can't throw out the cuttings fast enough, and your deck is getting close to clogging.

For a really thick mat of grass to get a 4 inches up is a LOT for your deck to handle, and it is being overloaded. I suggest that you try cutting your grass when it's growing this fast twice a week, OR set the cutting height on the deck to just cut the top 2 inches off the top of the grass, rather then 4-5. If you want to use this technique to get BACK to your desired grass height, then your going to have to mow twice, once to take off the upper 2 inches, and then a second time to again take off another 2 inches of cut.

If your bagging it, try removing the bagging system. That will allow the deck to clear the cuttings within it faster, but your going to have windrows of grass clippings if you do that.

 

[rebmo]

First, Thanks for all the help and advice. Really helping me get moving along figuring this machine out.


Yeah, did some inspection today. Lots of issues. I bought this machine late last years cutting season and had also just moved which we are finally digging out of. The PO said he had maintained the machine and I didn't have time to really go over it until now. Bad plan, I should have dug in sooner but again no time. It has run and worked great until the thick spring grass.

So now that I'm digging in, here's the problem list.
Air filter - very gunked and the outer filter deteriorated (new on order) I blew out the paper filter and the RPMs seem higher after cleaning. I ordered the whole tune up kit since it does not look like it's been done for years.

The PTO drive belt on it is a thin belt and the "vibration" I'm getting is the belt slapping the covers since it's flopping around so much. There is way too much play and it does not appear to be the right belt. The deck belt itself is a much thicker wider deeper belt and turns pretty easy by hand (so not too worried about the deck belt and bearings). I had greased the deck bearings but did it again and they still took a bit of grease to fill. So the blades have been sharpened and balanced and installed correctly, but the PTO belt is slipping and too small, and then the next problem.

There is an oil leak. It looks like the typical crakcase gasket leak so I have a new gasket and sealer and now need some time to get on it (2 day stretch). I have a real deal JD PTO dirve belt on order. My dilemna is I may need to use it for a couple weeks before I get to the oil leak. That's a bad expensive plan if I kill the new belt, but not sure I have any other options. Any thoughts, the oil is working it's way down to the PTO clutch and not sure I can stop that. I'd love to shove a rag in there somewhere to absorb it but no good place.

So I can cut grass with the crappy thin belt, but I do have to wait for the blade rpms to get going, and have to go super slow. Still I can see some lack of high speed cut in the thick parts. The grass looks to be getting pushed down and even missed in some spots, so I suspect the thin belt just can't handle that, period. I also noticed, no matter what, there is not much grass velocity out the chute. I noticed even my neighbors Simplicity LT is blowing it out much further. I'm seeing grass blow out maybe 12-18" and very weak with sputtering clumps coming out in the thick stuff.


I may work on my other Allis Chalmers 718 and get that one going. Same problem with the blades stopping, cheap PTO drive belt and slips in the thick stuff. I'll see if I can get a new belt for that one (no oil leaks either) and hopefully get by with it until I get the oil leak fixed on the JD. BTW, I do check the oil and add every time I cut.

Thanks for all the tips, I'm learning fast and the hard way hehe. I'll report back on further progress. Should see some real improvement with a new PTO belt and the higher RPMs.

Reb

 

[rebmo]

Just an additional summary. Even with the lower RPMs due to the dirty messed air filter, it was not bogging due to the belt slippage. I can get down on my hands and I'm really surpised the belt turns the deck at all. As mentioned in one post, I will possibly bog the motor with a proper belt. I should see grass blowing out the chute hard too when I'm at the right speed and the deck is running at the right rpms.

Should be interesting when I get the OEM belt I ordered. Ironically the higher RPMs with the cleaner air filter now slips the belt even more. So what a cluster along with the oil leak. I maintain all my stuff well, but working my way into this new to me used machine is a journey. I'm committed to resolving the issues since I'm only into the machine for about $900. Can't really afford new so fix fix fix until right.

Reb

 

[rebmo]

Just checking in with some progress on the cutting ability in thick grass. I recieved the tune up kit and the new belts. Installed the JD OEM Deck PTO drive belt which was much beefier than the belt the belt that was on the GT. My grass was up to about 4" and getting pretty thick again due to some steady soaking grain early this week. The new belt was actually much harder to get on and had to roll it onto the deck pulley where the other just popped on. This was a early indicator even before firing up the GT, that the new belt was going to be a big improvement.

So I fired up, dropped the deck, and engaged the PTO. With the blades turning I headed for the thick 4" grass at speed 4 of 6. As I got into the thick grass it cut and blew it out the deck just fine. So I put it up to speed 5 and it still handled it fine. Then up to 6 and it was still cutting and not slipping. It gets a little bouncy in spots due to the terrain, but now the GT 266 cuts just fine without the PTO drive belt slipping and burning. Oh, and I realized I had the deck set at 2.5" instead of 3" since I had it set at 2.5" for my thinner EZ cut front yard.

So I'll do a tune up this weekend and plan to do the oil leak fix ASAP. This will require a motor pull so I'll need a day or 2 to get through it and put a new crankase gasket with sealer. I should be good to go then.

Thanks for all the tips. My big takeaway to share is that OEM belts are worth it. Maybe there are quality OEM replacements, but for the grief I had, I would not bother. Go Green. It took my 1/2 the time cutting my 1 acre lot at speed 5 and it did a much nicer job appearance wise.

I have a new drive belt coming today for the 1978 Allis Chalmers 718 I have and that looks to be the magic on that tractor too. I look forward to running that GT. It's an all metal machine in really great shape. Strange, both machines had cheapo belts on the PTO drive, but I suppose some folk take the cheap way out before selling. Buyer beware.

All the tune up ideas prompted me to give the JD a full tune up. Obviously maintainance is Key on GTs.

Thanks again all,

Reb

 

[uglyboywith11fingers]

Thanks for all the tips. My big takeaway to share is that OEM belts are worth it. Maybe there are quality OEM replacements, but for the grief I had, I would not bother. Reb

sounds like your belt problem may have been that it was the wrong size ie: too long. But I agree with you on sticking with OEM belts. I tried one from TSC a few years ago, cost $20some bucks as opposed to the OEM being over $50. The TSC belt was the right length, but just came apart in a few weeks.
TSC replaced it for free, but next one shredded in short order also. OEM belts last about 5 years.

Pete

 

[rebmo]

I got ambitious today and pulled the 17hp kawa off the GT262 and fixed the oil leak. Put it this way, there isn't any rust on the frame, with all the oil that was flying around under the motor. Obviously not good for belts though.

So I was impressed with how easily I was able to pull the motor. The PTO and drive clutch took the longest with the keys having been there since 1992 but not too hard. When I pulled the crank cover off it was easy to see how the oil was leaking. The original gasket had folded inside the crank and there was just metal on metal for 3" or so. This thing has been leaking since day 1 it appears. So I put the new crankcase gasket on and used moto-seal on both sides and put it back together and did a full tune up, Oil, Filter, plug, Air filter & foam w/oil, and fuel filter. It was way past time. So, remounted the motor, put most of it back together, except the hood and it fired right up and ran fantastic. It does seem to run at higher RPMs.

So I took it back to the shed and attached the 48" deck and took it through the thick stuff and it was blowing out grass like mad with a 2.5" cut height.

I had been looking at the deck and noticed there is a mulching kit installed, but the output chute hole perfed blocker has been retracted all the way up. Therefore it does not restrict the output. I'd love to mulch with this deck. Has anyone had luck with mulching with at 48" JD deck? I may have to run slower thatn full speed, I assume I would have to lower the output blocker to mulch effectively. Dont' know if I have mulching blades either.

So next question is, Can you mulch successfully with a JD 48" deck and doest the blow out shoot blocker have to be dropped which I'm assuming is a yes.

Thanks for all the great ideas. Tried them all and each was part of the overall improvment. I'm cutting great again.

Reb

 

[Mark Page]

I have a GT275 I bought new in '98. It has a 17hp Kawa and a 48" deck. We use it on all the tight spots that our 7' Woods mower won't fit. I occassionally mow our 1 acre back yard because it does such a nice job. It has a hst. I tried a set of mulching blades once and all they did was make clods.
My point is to replace the blades no matter what else. Even though you're gonna' get screwed, buy Deere. I sharpen them once and then replace them.
You don't know if the previous owner abused it by running over sticks,limbs or rocks.
Are you sure the deck is level?

 

[RandyBell]

I have a JD LT180 with the 48" deck and I usually cut no lower than 2.75".
In the fall I put a plate on the discharge to hold the clippings, and leaves in for more chopping, I have to run a little slower ground speed but still have good results. I have the same 17hp Kaw in mine.
Sounds like the work you have done on yours was well worth the time and money.

Good luck
Randy

 

[tcartwri]

In heavy grass like yours I prefer a high lift blade.

 

[rebmo]

Well, here's what I ended up learning & doing. I was interested in a mulch kit for the deck since I didn't want to bag so I started looking at them. Turns out my deck had the mulch kit with the outlet block off rasied all the way up. Some folks report success with mulching and some don't. Those that had success all seemed to suggest slower speeds. So I took note on that, but also read of some folks using gator mulching blades without the "mulch kit" for the deck. So I ordered a set of 3 gator blades and pulled the "mulch kit" from the 48" JD deck. With the motor in tip top shape, new belts, a clean greased deck with new blades and a wide open chute off I went. The results were great. Although it's been dry for a couiple weeks now and there is not much thick grass, the thick grass I encountered I coiuld easily handle at speed 5 of 6. It probably would have cut fine at 6 but the ground is getting so dry the GT262 starts to bounce so I backed off. With the mulch kit out the deck blows out a good 3 ft or more going through thick grass. The cut was really nice even and flat. I think it was really time form my old blades to go. The deck runs quieter and smoother. All is good. I'll just have to see how it handles the really thick fall grass. We had very heavy rains last night, but there is a lot of brown in the semi dormant grass and we are now hitting the summer weather here in Wisconsin. So a lot of things done on the GT262 and it now runs and cuts like a champ. Feels good to have it up to par as far as maintainence. I may try the mulch kit later but for now there is no clumping of grass and the deck chops it an blows it out like mad now. So I'll report back in Sept/Oct when the grass gets thick again.

Thanks for all the help and ideas, greatly appreciated. Don't hesitate to ask if you have any questions on the crankcase gasket replacement.

Reb

 

[Adamg7720]

the tall grass CAN be mowed in one day down from 4-1/2in to 4in, down to a yard in one day
first-check the blades: sharp and properly installed. second, belts, third-everything greased, etc,. i have a John Deere 455(22HP) with a 60 inch deck. my sister in laws back yard was 3 times that( approximately 13- 19". what i did, was adjust my deck to where i could get the most cut w/o bogging thi engine( something you DONT) want to do. then i kept cutting it in half everytine, eventually working it back down to looking like a yard again. one thing i do like to do though, is as im going around, mow it down really good( the heighth i wan) and then and taking the cut grass and blowing it to that spot. i was able to work what was about 2 acres of tall, unwanted grass, down to a yard in about 2.5 hours. i hope any of this helps. Again, whatever you do, you DO NOT and i repeat, DO NOT, want to put any "load" on the engine, which can cause unwanted wear and tear on any engine.

 

[pace1]

I have a John Deere lt180 mower. The deck will only turn half speed. All the pulleys, spindles, and belt have been replace. I have tried adjusting the belt and nothing works. If anyone has had this problem please HELP.