Craftsman 917.270750 18hp Briggs 42" cut belt, spindle, pulley problems

fmitchelltx

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  • / Craftsman 917.270750 18hp Briggs 42" cut belt, spindle, pulley problems
I am having a problem with my Craftsman 42" 917.270750 riding mower. I am having a big problem with the deck belt on it. Over the past years I have had to replace the deck spindle and pulley on the left side several times. I may have run over things without seeing them from time to time but not anything that would do visible damage. I live out in the country on a dirt / rock road. I must put a new deck belt on often now because it stretches out just enough not to work after mowing most of the front yard. I am getting noise when I let the clutch / brake pedal all the way out now. The noise is not noticeable until pedal is all the way out. Motor running may be hiding quieter noise though. I have to keep the pedal about a quarter of the way down when mowing or the noise is as loud as the motor. Mower can be in neutral or any gear. The drive belt is new. I replaced it recently as the mower was getting sluggish to move when in gear. I just replaced the left (non discharge side) deck spindle and pulley again. The ears were broken off again. I have replaced this spindle and pulley several times over the years. Grooves in pulley are always worn smooth and hole is enlarged. I am thinking it may be a slightly bent engine pulley. This is the only thing I can think of. I do not see anything wrong with any pulleys when it is off.

How hard is it to replace the engine pulley? I think I would have to remove the mower from the frame to replace it, correct?

When I purchased the mower several years ago, there was no deck belt on it. The previous owner used the mower just to take the kids for rides, not mowing. He said the problem was with the deck if I remember correctly. I replaced the spindles, pulleys, and belt on the deck after I got it. It has been working, mowing, for several years since, but has never been 100% right it seems. The problem is now to the point that if I want to mow, I will have to replace the deck belt more than likely. I do not remember hearing the noise before I replaced the drive belt a month or two ago. Sometimes it is hard to get the shifter to move, but normally it drives fine. No noise from the wheel areas. As I say, if I let the pedal out, it makes a loud continuous noise. The two belts, drive and deck, are installed correctly.

Could the problem be a slightly bent engine pulley or does it sound like something else? It could not be a bent shaft coming out of the engine could it? The motor is strong and runs well for an old mower.

If anyone could possibly assist me in determining the problem, it would be greatly appreciated.

Thank you
 

bertsmobile1

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  • / Craftsman 917.270750 18hp Briggs 42" cut belt, spindle, pulley problems
The 3 bolt spindle housings are easy to break if you are hitting hard things like burried rocks & tree roots.
Once the crack the splindle pulls over to one side causing the pulley to be out of alignment
There are several different thickness of spacers that go under the pulley and again a few variations in the nut and if wrong ,or not tight enough the pulley will strip out on the spindle spline.
You can not over tighten that top nut, if you get my drift.
The bottom bolt will self tighten so no need to do it any tighter than specs.
A belt that is too short will also put too much strain on the pulleys as will a standard belt that is not a covered kevlar fibre belt which is designed to slip when overloaded.
The standard blades are quite light and bend easy, using heavier blades makes this worse.
I replace about 20 or so of these spindle housing a year, usually on contractors mowers where they are always mowing different yards.

You can also try a belt that is 1" longer which will slip rather than break things.
If you have a manual PTO it will have deep pulleys so the belt does not jump off when it is slack to turn off the blades.
Because the pulleys are deep people fit 5/8" ( B section ) belts rater than 1/2" ( A section ) belts and that rips the s..t out of the pulleys spindles.
 

fmitchelltx

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  • / Craftsman 917.270750 18hp Briggs 42" cut belt, spindle, pulley problems
Thank you for the reply. The belts are okay. If I was to put a longer one on, the blades would not turn at all. I am using the OEM length belts required. Could my problem be the engine pulley? That is the only thing I have never replaced. I go through the deck spindles and pulleys quickly for some reason. They have broken when just mowing the yard as usual, no obstructions get near the mower.

Can the engine pulley just wear out? I just watched a YouTube video that showed how to replace this pulley. It looks simple to replace. One of the videos I watched said the pulley can wear out with age. My mower is probably around 15 years I would guess. I really don't understand how this would happen. This is the only thing I can think of.

Thanks
 

7394

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  • / Craftsman 917.270750 18hp Briggs 42" cut belt, spindle, pulley problems
Noise when clutch pedal is all the way out.

Long ago my craftsman was doing the exact thing. It was the clutch linkage rattling around in it's holder on the Right side. Follow the linkage towards the rear, it goes along the inner frame rail, if that is it, you just need to wrap the bracket in rubber or the linkage, to stop the rattle.

Spindles: If you mow too fast that mower will eat them steadily. Gotta mow in 3rd gear.
 

fmitchelltx

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  • / Craftsman 917.270750 18hp Briggs 42" cut belt, spindle, pulley problems
Thank you. I will look at that. I don't remember it making noise before I replaced the drive belt recently. Do you know if there is a video that I could look at to make sure I do it correctly? I looked on YouTube but am not 100% sure what I am looking for. I will keep it in third and see what happens if I can get it fixed.

The deck belt spins all of the now too. In the past, I would engage the PTO to get the blades to spin and cut. It is as if the PTO is off but the blades are spinning. The blades spin now but they will slow when mowing. The mower does not cut now. I no longer hear the blades engage when I move the PTO lever to engage them. I hope that makes sense.

Thanks
 

fmitchelltx

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  • / Craftsman 917.270750 18hp Briggs 42" cut belt, spindle, pulley problems
As I watch YouTube videos, I am now wondering if my problem could be a bad clutch / PTO cable. What are the symptoms of a bad clutch / PTO cable? it has never been changed. Can it or the spring stretch? The spring does not look like it has stretched or is damaged.
 

bertsmobile1

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  • / Craftsman 917.270750 18hp Briggs 42" cut belt, spindle, pulley problems
Pulleys drive the belts via the sloping sides.
Over time the belts wear these sides so the space becomes bigger and the belt runs deeper in the V groove and the belt gets looser because it is effectively running around a smaller diameter.
A pulley needs replacing when the belt is running on the bottom of the groove indicated by the bottom being polished shinny and the belt slipping under even light loads.
The other reason is physical damage usually caused by picking up rocks, Nicks & bends in a drive pulley can usually be smoothed over,
Very rarely the pulley will bend on the shaft but that is extremely rare.
With used machines all sorts of things can happen.
I had a customer who was forever bending blades and wearing out discharge chutes.
Finally he did in a pulley so I ordered a new one , It was 1.5 " larger so someone had fitted pulleys off a 32" deck on a 42" deck thus the blades were spinning near twice the design speed.
The faster a blade spins the easier it will bend. So now with the correct pulleys he no longer eats blades or throws debris over the fence, however he does complain that the discharge chute keeps on blocking ( you can't win them all ).

A stick no thicker than your thumb can break a spindle if it jambs between the blade & the inside of the deck, even really soft wood like spruce or pine .
A deck that is too low at the front will also tend to break spindles every time the deck scalps.
Running heavy blades like Gators will break the spindle housing because they do not bend when they hit things like the thin AYP blades do.
A bad idler pulley or tensioning pulley will set up vibrations that can crack spindle housings.
A tension spring that is too heavy will not give and allow the belt to go slack when some thing causes an instantionously stop of the blades and cauase higher failures of the spindles than usual.
Using standard bolts to hold the spindles in can have them back off and thus cause the spindle housing to break
Then there are things like a bent deck.
Finally there are a lot of substandard spindle housings out there in ebay land that were rejected by Kohler or Murrys factories in China, sold off at auction to whoeveeer will pay the best price , get into the hands of disposal merchants ( usually in Hong Kong ) get sold in batches of 10 to 50 to ebay merchants in USA & Australia then flogged off to unsuspecting owners at around 1/2 the price of aftermarket or 1/3 the price of genuine.
I see a lot of these in my rounds.
Down here original housings are $ 75 retail, aftermarket are $ 50 and you can pick these up from what looks like a real mower shop on evilbay for $ 20 with free postage.
The bearings alone are worth $ 25.
 

7394

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  • / Craftsman 917.270750 18hp Briggs 42" cut belt, spindle, pulley problems
Do you have the correct belt on that deck ?

I don't know about any u-tubes, sorry.

There is no actual clutch, just the engagement lever that has a cable routed to the idler pulley bracket on the deck. When you engage the lever (by steering wheel) it pulls the pulley bracket so the belt gets tight & engages the blades.

That can be adjusted to one position or another. (at least on my former 1998 craftsman 917 xxxx)
 

bertsmobile1

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  • / Craftsman 917.270750 18hp Briggs 42" cut belt, spindle, pulley problems
As for the drive, if the brake/clutch pedal pulsates then you might have a bad pulley or be missing a few lumps out of the belt.
Drain the tank remove the battery remove the deck,
Stand the mower up on its bum so you can see what you are doing.
Check all the pulleys in the drive system, rotate them to make sure they spin freely , cleanly and quietly.
Check them for flat spots or deep grooves. If in doubt replace them, they are cheap I replace them at 500 hour services on my customers mowers regardless.
Then turn your attention to the tensioning arm, If you have not bothered to clean & lube it chances it has flogged out oval and will need to be replaced or welded up and recut round.
Check the rear pulley for stuff squashed down hard into the V groove.
Check both the front & rear pulleys for a polished appearence in the root of the V.
If the root is polished, the belt has been running too deep so either the belt is worn way too thin or the pulley has worn way too wide or a bit of both.
A 150 " deck belt only stretches about 1/2 " before it fails so stretch is not a problem except for EWE TUBE Sheep because the belt is reinforce with kevlar fibres which have almost the same tensile strength as steel.

A common fault on this style of mower is debris building up under the frame preventing the clutch/ brake pedal fully releasing so you do not get enough tension on the belt.
 

fmitchelltx

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  • / Craftsman 917.270750 18hp Briggs 42" cut belt, spindle, pulley problems
Pulleys drive the belts via the sloping sides.
Over time the belts wear these sides so the space becomes bigger and the belt runs deeper in the V groove and the belt gets looser because it is effectively running around a smaller diameter.
A pulley needs replacing when the belt is running on the bottom of the groove indicated by the bottom being polished shinny and the belt slipping under even light loads.
The other reason is physical damage usually caused by picking up rocks, Nicks & bends in a drive pulley can usually be smoothed over,
Very rarely the pulley will bend on the shaft but that is extremely rare.
With used machines all sorts of things can happen.
I had a customer who was forever bending blades and wearing out discharge chutes.
Finally he did in a pulley so I ordered a new one , It was 1.5 " larger so someone had fitted pulleys off a 32" deck on a 42" deck thus the blades were spinning near twice the design speed.
The faster a blade spins the easier it will bend. So now with the correct pulleys he no longer eats blades or throws debris over the fence, however he does complain that the discharge chute keeps on blocking ( you can't win them all ).

A stick no thicker than your thumb can break a spindle if it jambs between the blade & the inside of the deck, even really soft wood like spruce or pine .
A deck that is too low at the front will also tend to break spindles every time the deck scalps.

Running heavy blades like Gators will break the spindle housing because they do not bend when they hit things like the thin AYP blades do.
A bad idler pulley or tensioning pulley will set up vibrations that can crack spindle housings.
A tension spring that is too heavy will not give and allow the belt to go slack when some thing causes an instantionously stop of the blades and cauase higher failures of the spindles than usual.
Using standard bolts to hold the spindles in can have them back off and thus cause the spindle housing to break
Then there are things like a bent deck.
Finally there are a lot of substandard spindle housings out there in ebay land that were rejected by Kohler or Murrys factories in China, sold off at auction to whoeveeer will pay the best price , get into the hands of disposal merchants ( usually in Hong Kong ) get sold in batches of 10 to 50 to ebay merchants in USA & Australia then flogged off to unsuspecting owners at around 1/2 the price of aftermarket or 1/3 the price of genuine.
I see a lot of these in my rounds.
Down here original housings are $ 75 retail, aftermarket are $ 50 and you can pick these up from what looks like a real mower shop on evilbay for $ 20 with free postage.
The bearings alone are worth $ 25.
u


Thank you very much. I am going to check the clutch cable and linkage today. Hopefully I can figure something out today,
 
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