Craftsman GT3000 "MUTT" Part II

Mutt has come SO far since the first time I saw it. I wish I could have stuck to one tractor all this time. I'd have more $$ and probably have something bulletproof.

@RichieRichOverdrive i didn't know you did 3D printing, did you use PLA or PETG filament for that Mikuni adapter?

MightyRaze wrote:

Mutt has come SO far since the first time I saw it.  I wish I could have stuck to one tractor all this time.  I'd have more $$ and probably have something bulletproof.

It’s really neat at this point that I’ve had this tractor longer than most people have been in the mower game. The best part of having a tractor for half your life is that you come to feel perfectly at home on it. I know every quirk, balance point, and ability of this tractor. Richie Brown said I was his favorite person to watch ride because I’m so wild on it. That was pretty cool to hear. Now as for it being bulletproof…not really haha. The 820 is 100% a limiting factor.

ranch king pro 08 wrote:

@RichieRichOverdrive i didn't know you did 3D printing, did you use PLA or PETG filament for that Mikuni adapter?

Just plain old PLA+! I can’t believe it holds up so well! I do still make spares of these adapters to bring with me to rides. I’m pretty new to 3D printing honestly, just have a junky old Ender 3 pro. It works well enough, I suppose.

Now what’s going on?!!


Dang old trailer spindles…cut to length and drilled to sleeve right over the existing spindles.


Etc.


You get the idea. Just gonna trim the spindles off a bit and zap these on. Should be reversible too if ever I wanted that, just cut the weld and pull them off


Now for some 4x4 to 4x156 wheel adapters! 3/4x6” material…an expensive but exciting waste of material! Well, it would be if I hadn’t got the material out of the garbage.

@RichieRichOverdrive Nice dude!, I have an Ender 3 and a kingroon kp3s they both work great for me I've got to say the layers are seamless on the kingroon it has a very small building plate but for like 150 bucks you can't beat it

Got some wheel adapters made up! Just some dang old milling and drilling and tapping. I happened to have a countersink that was about the right angle for the lug nuts, even.

Got the setup on the tractor this morning. Front width is now 40”, down from 41.5-42ish. That means I brought my scrub radius in a little under 1” on either side, which should hopefully be easier on stuff. I can also shave another 1/4” off the spacers if I wanted to, which would bring me down to 39.5, which I don’t think is necessary.


I am going to have to figure out something for new spindle caps, as these will undoubtedly get ripped off.

Interesting to note that mutt has an identical track width front and back with these mudlites mounted!

Last minute GER prep, just greased some stuff and tightened the pivot on the front axle. Went for a shakedown run and hopped this log that was big enough to belly the tractor out. Fun stuff!

While the wheel horse saw the most riding at GER, I still went back to mutt for the most serious trails and when I was inebriated enough to need a tractor that my instincts are tied to. On a night ride I had her sitting sideways between a creek bank and a tree, one rear rim spinning over a rock and the other tire rubbing the tree. She sat running on her side for like 2 minutes, can’t believe she didn't stall haha. Says a lot about a good mikuni carb.

Here me and Richie Brown were coming up Cripple Creek and I crawled up a slanted rock next to a super deep hole that would have easily rolled me if I dropped in. The tree at the top I had to squeeze by and the mud on the rock made it a good challenge, but she came right up it!

Went riding with the gf today.


Developed a problem with one cylinder dropping out when the engine was at operating temp. Figured a coil issue, or plug wire issue. Could definitely see that being possible.


So I swapped the coil to no avail. Turns out one of the JUNK new champion plugs would develop a miss when hot. Go figure. Swapped to an old pair and she’s running good now. I need to find another brand of plugs that can be trusted…and fits my existing plug boots…

I have had 4 of my last 6 champions just randomly die or start misfiring on 3 different mowers.  Right plugs called for on the engines and proper gap.  I just switched my last one that died to NGK.  See how that goes.

Was looking under mutt last night. I think I have plenty of room to string a Sears style bellcrank steering and fix my drag link and bump steer woes. Bellcrank will also give my steering response rate tuneability, or at least a better option when I build it.


I think I will still use the rack and pinion, just repositioned somewhere towards the center of the frame.

RichieRichOverdrive wrote:

Went riding with the gf today.


Developed a problem with one cylinder dropping out when the engine was at operating temp. Figured a coil issue, or plug wire issue. Could definitely see that being possible.


So I swapped the coil to no avail. Turns out one of the JUNK new champion plugs would develop a miss when hot. Go figure. Swapped to an old pair and she’s running good now. I need to find another brand of plugs that can be trusted…and fits my existing plug boots…

I sell Champions at work, and they seem to be the one brand people don't like. Can't go wrong with NGK.

Usually if I get a bad champion I’ll just find an older champion to throw in

I was thinking on taking mutt to Haspin but a ride around the yard made me realize my shift keys are entirely wiped out. Guess I got to either find or make another set of those. Cost me like $40 for the last set.

Also need a new carb boot that isn’t chinesium. This one is super cracked.

Hey, I offered you the two I had and you said nooooo

Tried to finish off this 820 lol. Couldn’t get it to pop.


Dropped the trans


I saw one spot where a crack spread past the hole i drilled. Seems like the cracks that were already there just opened up more

Shift keys looked about how I expected


Locker is holding up good, no key shear


Snapped off several bolts in the new trans and got it open. Nasty grease!

So this newer case is an 820-040, the older case is an 820-018. They do have the same gearset as the -016 as well. Seems like the only difference externally is the short 5/8” input shaft on the -018.

There is however some improvements to the new case. Here is the older case…


…and here is the newer one. See the added material behind the input shaft? This seems to be to combat the exact issue i was having with the case cracking.


Notice also in the above photos that the input gear is slightly different. I would imagine that with the variations in input bevels they are interchangeable between cases as a set(with the lower gear) but not individually. This is however only speculation.

The -040 is also uses the a tall shift key shift shaft and the shifter fork that goes with it. Being a short shifter this is still a 1/2” shifter shaft and not the 9/16” of the tall shifter shaft.

Notice the rounded end on these keys, rather than coming to a point. Should be a bit stronger than the old design. They are a bit heavier duty in general.


Only about the thousandth time I’ve had this view lol


I had to put a shim under the upper snapring on the input shaft. There was some movement up and down and when all the way down the end of the input shaft would interfere with the upgraded reverse chain.


Also, didnt get a picture, but this new 820 uses a china brand upper input bearing. I actually swapped it out for my old NSK upper bearing from the old 820, that still spins as good as new.

Nice post!  Good to see the differences in the versions.

Got everything back together. Managed to beat this cage onto the newer 820 with a little finagling and drilling holes oversized.


Immediately took it out and hopped some stuff


Unfortunately my input shaft is still getting into the reverse chain in there, I can hear it. RROD Racing Team has made the executive decision to ignore the hell out of that funky noise and just let the transmission fill itself with glitter until something either breaks or stops interfering.

Just ordered a new VM34 mikuni for this old pig. Gonna see if i can get the same whoompow out of this engine that the china 34mm gave it (before that carb came apart lol)

The china one just that fragile?

They just can’t get anything in the float bowl right. The “maikuni” one i had was great when the needle or float wasnt randomly sticking. The no name 34mm needed modifications right out of the box and I finally gave up on it when the spring loaded needle disassembled itself. The VM34 should be the real version of the china 34mm

The current VM30 has the oppy very snappy but feels choked on the top end.

VM34 got here today. I bought a proper (expensive) carb boot a while back so I’m making a new adapter plate for that. The old cheap carb boot was starting to dry rot already.

Got the adapter all made up. Used the 4 jaw in the south bend to bore a tapered hole to match the different sized ports.


Holes for mounting the boot


The other mounting holes are tapped blind from the backside as to not facilitate vacuum leaks under the boot.


The snorkel adapter from the old 34mm even popped right on.


Painted the nose cone/grille. If the color turns out alright i may do the fenders too.

Wound up going down a few sizes on the main jet. Not sure the actual number size but it was a .055” hole. Still playing with the needle position. I tuned the engine to run smooth at all rpm in the shop but once i put the engine under load it fell flat on its face. Had the needle all the way down. Raised the needle up two spots and she’s got tons of power now. Just isnt smooth at one rpm at no load. Sort of sounds like anti-lag the way it chops a bit. Might try for one more slot and see if that improves anything.


Painted the nose cone and cut and painted a little grille screen


Put a new headlight in one side and it burnt out like the second time i turned it on. Same side as last time. Maybe i should redo my wiring up there. That side is a bit dimmer, must be drawing more amps and burning the filament out or something.