Murray Widebody build

[jhodgson53]

Well, I finally sorted out the two mowers that my neighbor gave me back in the winter. I had originally intended to use the Murray as my grasscutter and the MTD/Huskee as my project mower, but it turned out that the deck on the Murray was hopelessly worn out while the MTD only needed a belt and a thorough adjustment of the deck suspension mechanism. So, I'm cutting grass with the MTD.

The Murray is a 20 HP, Briggs I/C Diamond twin with a 6 speed trans. It runs, drives and shifts just fine. So far I have removed the deck and most of the deck suspension mechanism. (One bolt is giving me a fit!)  I have removed the stack pulley and am going to get a slightly larger drive pulley for the engine. The motion drive belt is very worn and cracked - I'm surprised it didn't come apart while I was tooling about in the pasture.  As it sits, the belt goes around both sides of the steering shaft. Is this correct?  There are no idlers or other guides that would put the belt on one side or the other of the steering shaft, but I don't see any way, short of raising the shaft, to get the belt off and on. I haven't got the mower up high enough to eyeball the steering pinion, but I can't feel a bolt head or nut there. Any clues? Snap ring, maybe?

I'm looking at different steering / front axle options. I have on hand a golf cart front axle with spindles, and I also have a center-steer rack and pinion unit from a Kart. Also looking at ACME Mowersports axle.
Thanks for your input!

-J.B.

[jhodgson53]

Well, I finally tilted the mower on it's side far enough to eyeball the steering shaft and I see a snap ring holding the pinion gear on the shaft. If the weather cooperates I'll be taking that off tomorrow and removing the drive belt and replacing the front pulley with a 5-incher. (Where did I put my darned snap-ring pliers?) I finally got all the deck adjustment hardware off and I made a cover plate for that lever's slots, using an expired license plate. (I hate to see good aluminum go to waste!)

I haven't dropped the transaxle yet but I fear the rear pully is going to be a bear. It's very rusty from being under the battery box; after vigorous brushing with a stainless "toothbrush" and some WD40 I managed to remove the remains of a snap ring with a small screwdriver! I'll be giving the pulley/input shaft several hours of treatment with PB Blaster and maybe some alternating heat/cold (heat gun and CO2 extinguisher) to try and break the rust free before getting down to brute force. I don't plan on going any smaller than 6 inches on the trans pulley. I want plenty of surface area contact between belt and pulley, as Chris and others have recommended.

I'm initially going to mount a pair of polyurethane bump stops to limit and dampen front axle travel, instead of welding or bolting the axle solidly. I'm working out the mounting brackets and hope to have something mocked up before the weekend is out. If I could find a short leaf spring that's not too stout. I might bolt the center of it over the axle transversely, and put a bump stop on either end of the leaf with the bump stop bearing against the top surface of the axle just inboard of each spindle. The idea would be to allow some controlled movement of the axle while improving stability over the stock setup.

I'll try and take a few pics this weekend even though there's not much to see as yet.

[NikoBellic]

Sounds like a nice project. I still haven't had time to mess with my PW but I'll get there.

[Chris]

I'd love to see a mower with a golf cart front axle, that would be awesome.

[jhodgson53]

Well, I've spent some time measuring and figuring on the golf cart front axle, and that's the way I'm headed instead of trying to make the stock axle work. I'm going to mount it rigidly, at least initially, with a piece of heavy 4" angle iron bolted to the front of the frame where the stock axle mounting bracket is currently located.  I will have to modify the cart spindle's steering arm with a bolt-on extension, to make the geometry more conducive to the mower's steering. The cart spindle's steering arm is on the back side of the right spindle, and at about a 45 degree angle to the spindle itself. I've already made a sketch of the piece and hope to get it fabbed up, at least a mockup, in the next week or so. I will also have to fab a tie rod, since the stock one wasn't included with the axle. I will be using 4 on 4 trailer hubs on the cart spindles; they're already ordered. A set of 8" rims and some 18 inch tires should make it sit about right if I keep 20" tires on the rear. 

 :question:Anybody ever do business with Jed's Wholesale Tires here in Tennessee?  They're a major distributor for all kinds of cart, ATV / UTV and ag tires/wheels, and they sell a lot on ebay. It's only about fifteen miles from me so I can pick up and save the shipping if I buy tires from them. Just wondered if anybody was familiar with them, their service, etc. Their ebay feedback is 100% positive so They can't be too bad, I guess.

Has anybody ever actually used a Hydro as a transmission only, with a chain drive to a rear axle?
I'm thinking this might be a good setup with a really strong rear axle versus the transaxle setup. I look at those little 3/4" axle shafts and see weakness.

later,
JB

[Chris]

Take lots of pictures!!!!

Ryf is using a hydro as a transmission in his mower-buggy, it works great for him. I plan on using a hydro (if I can find one) for my recovery mower as a transmission. Going to mount it sideways though so it acts as a transfer case too

[jhodgson53]

Man, that transfer case idea sounds interesting! Maybe a "phase II" project one of these days.

I'll be getting the camera out soon to document my progress. I ordered my pulleys from surplus center this morning; 4.75" front pulley and 6.25" rear. I think this will give me all the speed I'm interested in plus a reserve of low end torque.  I ordered two 8 inch, 4 on 4 golf cart wheels from Buggies Unlimited this morning also. Tring to get the steering geometry worked out. Sure wish I could figure a simple way to use the cart rack and pinion I already have on hand, short of having a jackshaft arangement from the axle, and steering arms going over the top of the engine, like I saw in someone's build either here or on heymow. 

Still trying to decide on a brake setup. Plenty to do!

Later,
JB

[Chris]

You could probably use the steering system with the jackshaft idea and some sprockets/chain. Could work out pretty well, vut I'm sure it would be complicated to setup.

[jhodgson53]

I registered for an uploader account but when I went to post pics it says I haven't been approved yet, so pending that I will post a few pics of the Widebody. My hubs arrived yesterday, so I'm anxious to get this thing all figured out and operational.
Spent the day finishing a new walkway for the house, so I'm resting my aching back and watching some NASCAR!

[Chris]

I'll go approve you now, I have no idea why that thing isn't sending me emails anymore.

[jhodgson53]

I'm doing something wrong. I uploaded the pics, the list shows up in the uploader file, but when I right-click on the icon and click "Copy," then go pack to my post, the "Paste" command is subdued like there's nothing on the clipboard.
Anyway, Here's the Murray in it's inglorious parking spot while the shed is in use for a carpentry project;
Grasscutter in background:  http://www.offroadmowers.com/uploader/files/56/Murray1.jpg

Here's a shot of the cover plate where the deck height adjustment lever used to be; deck in the background:   http://www.offroadmowers.com/uploader/files/56/Murray2.jpg

Used two bumpstops to replace the seat springs, for a more comfortable seat angle and less wiggle:
http://www.offroadmowers.com/uploader/files/56/Murray3.jpg

The golf cart front axle; dig those 1 inch spindles!:   http://www.offroadmowers.com/uploader/files/56/Murray4.jpg

My front hubs, trailer hubs with tapered roller bearings:
http://www.offroadmowers.com/uploader/files/56/DaHubs.jpg

My sketch of the steering arm add-on; still don't have the mock-up cut out:
http://www.offroadmowers.com/uploader/files/56/Steering%20arm1.jpg

At least you can see that this project isn't a figment of my imagination!

More later!
-JB

[Chris]

I see a bunch of really good ideas there!

[jhodgson53]

Thanks for the encouraging words!
This afternoon I dropped the transaxle and began trying to persuade the stock pulley off, since my new pulleys will be here this week. As I mentioned previously, the top surface of the pulley and input shaft are very rusty, but I've been soaking the joint with penetrating oil for over a week. I turned the unit over and removed the snap ring from beneath the pulley, and started the penetrating oil treatment on that side, which is practically rust-free. Tomorrow after work I'll start with the heat gun and maybe alternate with a CO2 extinguisher to try and break things free.  Looks like this pulley won't take much abuse from a puller. Trying to remember all the old tricks for removing rusted parts!

Interesting that the shifter shaft is so far to the left side of this transaxle, and the factory makes the elaborate linkage to put the shifter on the right side of the mower. Go figure.

I'm looking at reworking the brackets that attach the transaxle to the frame. There are two sets of attaching holes on each axle housing, and the stock brackets use the inboard set on each side. I'm considering extending the bracket to use the outboard holes as well, which should give some additional support to the axle housings. Might also make a good mounting point for brake calipers. I'll try and take a pic of this area tomorrow.

Working on brake system (on paper).

Later!
-JB

[Chris]

I really think I'm going to have to steal your idea for the cover plate, I like that a lot. I just left mine open and planned on welding all the holes shut one day (knowing I'd probably never get around to doing so), but your plate looks much cooler - adds that "bling factor"

[Ncredleg]

Some great ideas there. Thanks. Russ

[jhodgson53]

Steal away! The cover plate took all of an hour to make. After I removed the original slotted plate which held the deck height adjustment lever, I traced around it on a piece of thin cardboard taped to the plate, then transferred that to an old license plate and cut it out with snips and smoothed the sharp edges with sandpaper. The bottom two holes are where the original slotted plate bolted on. I drilled the other two holes in place to hit plenty of "meat" around the edge of the fender cutout. The original slotted plate has a tab that just extends under the fender at the top, but the license plate was just long enough to make it the way I did. I wasn't going for "bling" but it doesn't look bad; sort of like the plates and panels you would fab up in a racing sedan. And no cost other than my time and screws I already had on hand.

I'm trying to find that piece of 4" angle iron that I need to make the bracket for the golf cart front axle, without buying an eight-foot length which I'll probably not use in my lifetime. Everything I've found so far is either too small or way too big. I'm going to check tomorrow with a couple of fabrication firms that are close to my office. Failing that, there's a scrap dealer that picks up stuff from our fleet garage who may be able to help.

No luck with the transaxle pulley today. Heated and cooled, judiciously pecked and pried, all with an eye to not damaging the input shaft bearing, and no movement yet. Next step may be the Dremel with cutoff discs to cut through the pulley hub and get close to the shaft. Seldom have I seen anything so profoundly rusted stuck here outside the salt belt.

Best to all,
-JB
Posted on: July 06, 2010, 10:05:29 PM My new front wheels and new pulleys arrived today:

http://www.offroadmowers.com/uploader/files/56/wheels%20and%20puleys.jpg

The wheels are 8", 7"wide, 4 on 4.  engine pulley is 4.75, trans pulley is 6.25.

My work interfered with my attempts to procure the angle iron today. I hate it when that happens! Maybe better luck tomorrow!
Got home late and found the new stuff waiting on my front porch.
I'll take a few minutes in the morning to apply another PB Blaster dose to the trans pulley before I leave for the office; tomorrow evening will be my last attempt to remove the pulley intact, then I resort to the cutoff wheels.

Still trying to figure the most cost-effective way to mount a substantial brake disk on the 3/4" axle. Suggestions are welcome.


Later,
JB

[Chris]

Those are the same exact wheels I have on the back of my Toro. They still look good after sitting outside in the weather for two years

[jhodgson53]

Here are some Briggs and Stratton decals I ordered from their website; about 6 bucks for the lot.:

http://www.offroadmowers.com/uploader/files/56/BandSdecals.jpg

The big ones are about 18" wide by 8"high, and the small ones about 8" by 3". More bling, I guess?

It's officially 100 degrees here today, so I'm waiting for things to cool down a bit before venturing to the shed and continuing my torture of the transaxle pulley.   Or myself, as the case may be.

Ref the wheels, they seem to be very well made. They're zero offset so the front track won't be waaaay wider than the rear. When I eventually get four-bolt hubs for the rear, I'll get another set and maybe go to a 22" tire vs, the 20" ones I have now.  Surplus Center has some very nice 12" rims that would look so cool with a low profile tire, but for my purposes I prefer the taller tire which when run soft will to some extent compensate for the unsprung chassis.

Anyone ever use any of that rubber fender flare material around the rear fenders to cut down on splatter?
My tires already stick out a bit past the sheet metal, so I was just thinking......

Later,
JB


Posted on: July 08, 2010, 03:59:16 PMAnother thing: Anyone ever see a brake arrangement on a kart that has a "shoe" that actually rubs against the rear tire tread when the brake is applied?  My uncle had a dirt track racing cart when I was a kid, (45 years ago) and IIRC it had this type of brake. The metal shoe was covered with a thick piece of rubber, about 1/2" if memory serves. The rubber looked like and may have been a piece of tire tread. They worked very well as I recall, but of course we're talking about a light vehicle. I was wondering about this as a solution to my split braking system. It could be auxilliary to the disc brake on the axle, and I have a blade engagement lever on the right side of the mower that I could set up to apply the right brake if pulled back, and the left brake if pushed forward, or something like that.

Just thinking out loud again...
JB

[jhodgson53]

  FINALLY! I got the old pulley off the transaxle this afternoon. Had to cut through the pulley around the hub with the Dremel, then cut through the hub lengthwise down to the keyway,  then put a big screwdriver in the cut slot and PRY, creating just enough clearance to loosen the hub on the shaft.

I'm definitely going to put some anti-seize compound on the shaft with the new pulley. I'm anxious to get the drive train back together and see if and how much my clutch and idler pulleys will have to be modified, and what length drive belt I will now need. I have parts ordered for my new rear disc brake (mechanical caliper), but I rebuilt the stock trans brake just for giggles while I already had everything apart. I won't be doing anything adventurous until I get that disc brake installed.

Had to spend time today working on the grasscutter, which decided not to start on Saturday morning.  Finally figured out that it is the starter, go figure!

Later,
JB

[Chris]

I wouldn't mess with the on-tire brake because they're pretty much useless when you get them wet. I had a pedal-cart with one of those when I was was little kid, they were pretty much useless.

As for the transaxle/transmission disc brake. I've found that they work really good as a parking brake. I use to use mine way back in the beginning days of off-roading as the primary brake until I found out what happens when your chain falls off/snaps. Ended up going backwards down a very steep, large hill very fast.

[jhodgson53]

  Yes, come to think of it, we never raced that dirt track kart in the rain!

Im buying a 6.5" sprocket to use as a brake disc. See any problem with that, other than keeping fingers and toes away from the spinning sprocket? I could grind the teeth off, I suppose.

Later,
JB

[Chris]

Are you planning to use it as a sprocket also? You could get a go-cart sprocket for really cheap. I got a nice cross-drilled & slotted one with a hub for like $10 on ebay.

[jhodgson53]

My immediate plans are to use it for a brake disc only. I decided on the sprocket because they were easy to find with a 3/4" bore, like my axles, and without having to bolt them onto a hub they take up less space on the axle between the wheel hub and the trans case. I'll use the Dremel to grind a keyway in the axle where the sprocket will sit. I saw a pic of a gokart recently that used the drive sprocket on the axle for it's brake disc; the caliper was mounted at the three o'clock position with the chain passing above and below it.

I have daydreamed about eventually installing a chain drive to a more substantial live rear axle, using the current transaxle as a transmission only. This would probably require lengthening the frame to relocate the live axle rearward, or relocating the trans forward to preserve the stock wheelbase. Maybe when I get this one up and running as my workhorse, I might find another one to use as a "testbed" for an idea I have for a mower-based UTV of sorts, looking something like a Toro RER with the rear wheelbase extended to make it more "mid-engined" in nature, with a small utility bed or platfrom behind the seat. My purpose wouldn't be to conquer the Kalahari with it, but something handy and fun to use here on the farm, without spending several thousand dollars. Another project for another day!

No progress today on the Murray other than getting the new trans pulley on.  Bad thunderstorms with torrential downpour in the area kept me in the house nearly all evening after work. Ordered a new starter for the grasscutter.

Later,
JB

[jhodgson53]

  I got the steel cut for the piece I'm making to change the geometry of the steering arm on the golf cart spindle I'm using. That's the sketch I took a pic of previously. Hope to get it welded and drilled in the next couple of days. Ordered rod ends for the tie rod and steering linkage. Got my brake caliper today, and the brake disc / sprocket has been shipped. If rain slacks off I may make some progress tomorrow. My mowers are still sitting outside under a tarp while the shed is otherwise occupied.

Got a new starter for the grasscutter too, but the grass has got ahead of me, so it's back to the big tractor and 6' mower as soon as things dry out a bit. 

Later!
-JB
Posted on: July 17, 2010, 12:52:05 AM The mailman brought my sprocket / brake disc today. It's a great fit in the caliper.  I'll have to get set screws and a shaft key for it. Pics to follow.

Later,
JB

Posted on: July 17, 2010, 09:49:21 PMHere's a pic of the Airheart brake caliper I'll be using:

http://www.offroadmowers.com/uploader/files/56/brakecaliper.jpg

Hoping for a couple of dry days so I can begin putting the drivetrain back together. Once that is acccomplished, I can turn my attention to the front axle, steering, etc.

Later,
JB

[Chris]

Nice status updates, seems like you're currently the only active build on the forum

[jhodgson53]

That's a shame. I'm having a blast.

Mocked up the brake disc and caliper and I have clearance issue with the wheel. If I had a slightly smaller sprocket with a smaller diameter hub, It would put the caliper closer to the axle centerline and clear the wheel. If I used a brake disc with an offset hub:

http://www.offroadmowers.com/uploader/files/56/offset%20disc%20brake.JPG

it would move the assembly inboard away from the wheel. An auto disc is the only production piece I'm familiar with in that configuration, and that might fit the bill IF I can find a thin one (3/8" max) for an old, small car.

I'll have to look at the specs on some different sprockets first and see where that leads.

Later,
JB

[Chris]

I guess I don't understand what's going on, do you have a picture of it assembled?

[jhodgson53]

No I don't and I've disassembled it all now. Let me see if I can explain it better. There's not enough room between the disc and the wheel for the caliper to fit over the disc without the caliper rubbing the inside edge of the wheel rim. Either the wheel will have to move outboard (which can't be done with the stock mounting arrangement)  or the disc / caliper will have to move inboard. Or I get bigger diameter wheels. Or a smaller caliper.

I did find a smaller caliper on ebay;
http://www.offroadmowers.com/uploader/files/56/small%20mech%20caliper.JPG
I've messaged the seller to try and get the overall dimensions so I can see if it will solve my problems. It looks promising.

Also, I found out that a solid brake rotor for a Vega, K-car or Isuzu PuP can be bolted to a 4 on 4 hub, ditto for a Chevette or Fiat 850 with minor fitting with a round file. 
http://www.offroadmowers.com/uploader/files/56/fiat%20brake%20disc.JPG
http://www.offroadmowers.com/uploader/files/56/4on4rearhub.JPG

This also bears exploration. Like the sketch in the previous post shows, the auto brake rotor will move the actual disc surface inboard by a few inches, which is plenty. This will be a bit more pricey than the smaller caliper; about $20 for the rotor and $25 for the hub, vs $28 or so for the caliper. Plus, if the brake rotor is too thick for my current caliper, I'll have to get someone with a brake lathe to thin it down for me.

Decisions, decisions!

Later,
JB

[Chris]

Alright, I think I understand what's going on here now. I forgot you were running an transaxle and not a transmission.

What's the problem with moving the wheels outboard? Run out of axletube?


Edit: Check out how George Herrin mounted his brake setup.

More on the build. Here you see I am seting up the brake system. These are not new brakes but some I had and want to try on this build.


here is an overall view of the brakes and rotor. Yup its a big rotor but the bigger it is the less force needed to stop it. It is a motorcycle rotor redrilled to fit the MCP brake hub. Everything is setup so the rotor hub is against the bearing hub and I put a slit collar outside the brake hub to hold it all in place. The caliper is bolted to the frame with a couple shims between it aqnd frame to align it to the rotor.


Here you can see the clearance between caliper and tire. Tire 19 inches from center of frame. Thats the outer sidewall.

http://www.heymow.com/index.php?topic=1613.msg13238#msg13238

[jhodgson53]

  Yes, Mr. Herrin has a nice brake setup. 
In my case, you've got it, there's just not enough axle sticking out of the housing to accommodate all the pieces!
Running an axle like his, with the bearings up flush against the frame, it would be a snap.

I'm leaning toward trying the smaller caliper, if I can confirm that it's small enough to fit.

Went out to mow, and my grasscutter has a flat.   

Later!
JB

[Chris]

You could always replace the axle shafts with a single shaft.

If it makes you feel any better my grasscutter is on it's 3rd deck this summer, and it ate all the belts last week

[jhodgson53]

  I found another inspiration on heymow, a build by "a_little_wicked" features this beautifully fabbed rotor to accomplish just what I need.

http://www.offroadmowers.com/uploader/files/56/fabbed_rotor_heymow.JPG   

Don'tcha love it?  I'm having to give this idea a good long think. It would work beautifully on my transaxle. 

Heat index here 105, heat exposure warnings today and tomorrow. In the morning as soon as the grass dries, it's the big air-conditioned tractor and 6-foot mower for me; gotta get the place whipped back into shape!

Later,
JB

[Chris]

There's a good idea, never thought of that.

[jhodgson53]

After much thought, deliberation, measuring and re-measuring, and pricing of components, I've decided to try the automobile rotor. I'm going to look at some examples this week before I purchase one . I really only need a couple of inches of offset to make everything fit (actually, even one inch would suffice, but two would be better). I can use my current sprocket/disc as a hub, drill it to fit the rotor's bolt pattern, then fab the caliper bracket. A mechanic friend assures me that he can access a brake lathe to reduce the thickness of the rotor if necessary.  A number of vehicles use a thin unventilated rotor on the rear, even if they have the thicker ventilated rotor on the front, so I'm looking for one that gives me the best fit rather than a particular bolt pattern.

Later,
JB

[jhodgson53]

  And the winner is.... the rear rotor for a 91 Ford Escort, ordered and on the way, fifteen bucks and done.  As soon as it gets here, I'll mark the sprocket with the bolt pattern to be drilled, and check the rotor thickness against my caliper to see how much the rotor will have to be shaved, if any.

Later,
JB

[Chris]

Pictures! Take pictures!

[jhodgson53]

Yes, pictures will be taken as soon as the rotor arrrives and I start piecing everything together.

Later'
JB

[jhodgson53]

Picked up my brake rotor at the Post Office today, it actually should have been delivered Saturday but the mailman was apparently too lazy to drive down my driveway and get out in the rain to bring it to my front door, so he just left the notice in the mailbox. Whatever happened to "neither rain, nor sleet,... etc?" 

Looks good, but I haven't checked it against the caliper yet. I'll be in Incident Command school for the next couple of days but I promise pics will follow asap.

Later,
JB