1977 sears st8 build

Hello andy from south west Michigan here im new to the site so I figured I would put up a thread for my current build. Especially I don't see a whole lot of these st8 anywhere I don't know if they are rare or some thing but anyways. The tractor has been in the family since new but sat in the corner of a garage for like 25 years. My grandfather use to let me drive it around like a go kart he died when I was pretty young so those are really the only memories I have of him. So this build is t to radical because I wanted to keep it at least mostly stock looking, but to beef it up to handle a lot more than my xt1 cub cadet haha. So the low down on what I have done so far ground all surface rust off the frame and undercarriage and coated it in rubberized undercoating. I replaced the rolled steel front axel with a cast iron one and put slightly bigger front wheels on they are actually the rear wheels from a zero turn. Lately I have spent the last week swapping the 8hp flat head Briggs with a kohler command 22hp vtwin I freshened the motor up first with new head gaskets and rebuilt the carb. The swap was fairly simple had to drill new holes and make my own exhaust, but the wiring has been a huge pain. First I tried the harness from the donor didn't work they i tried to modify the st harness didn't work and finally said screw it and put in a couple toggles and a push button. Found out that the problems all relate to the smart spark electronic ignition so im looking into getting rid of that I actua think kohler makes a conversation kit bc it was so bad. Now I understand the basics of your standard pully swaps but this tractor is a unique beast bc it uses the peerless 2300 trans which is horizontal input but the st also uses a vertical shaft engine. It has a right angle gear box to convert. Originally I was going to do like a 4 on the engine to a 4 on the input side of the gear box with a 5 exit to a 3 on the tranny. But the tranny is only a 3 speed so now im thinking slightly bigger engine to 1-1 on gear box to 3 on trans. I don't want to lose much torque just like to get her up to maybe 10 to 15 mph. What I have left to do is sand blast all the body panels I assume im going to have to modify the hood a little bc the vtwin is a lot wider, I have to work out the pully set up and Id like to lock the rear end but I have found to much info on locking the 2300 that may be down the road bc it functions with no issues so don't know if I want to tear it down. Oh just incase anyone notices the weird black spot in the undercoating when I was putting the gas tank back in it leaked on the fresh paint was pretty pissed so I have to touch that up

Well can seem to get the photos to upload from my home I'll get them from my pc tomorrow

Sounds like a neat tractor. I like the idea of the right-angle gearbox a lot better than a belt twist setup, haha. Also is the trans a 3-speed with reverse? If so it'll be a Peerles 1200 series, the 2300 were a 4-speed with reverse. Both very beefy transaxles though. Looking foward to seeing some pictures!

AllisKidD21 wrote:

Sounds like a neat tractor. I like the idea of the right-angle gearbox a lot better than a belt twist setup, haha. Also is the trans a 3-speed with reverse? If so it'll be a Peerles 1200 series, the 2300 were a 4-speed with reverse. Both very beefy transaxles though. Looking foward to seeing some pictures!

You know you just answered a question that had me stumped for awhile when I looked the st8 up on tractor data is said peerless 2300 4 speed with reverse and I'm like I only got 3 over here haha. And I'm totally with you on the twist set up I didn't even know that was a thing untill I was pick through a GT at the scap yard. I saw a guy on another site that had the same gear box in his st10 but his went belt from motor to gearbox and then chain from gear box to trans.

Yeah, that model should be the sears version of Kal. (<---Profile Pic) or close to it which i think was a 2300. Curious what was swapped in. A 1200 or a roper that didn't have the high low? (I think the 1200 was better interchangeable) Can't wait to see the pix!

Day I brought it home

The print out from Sears part direct says peerless transsaxle model no 143. 2336 once the sun's up I'll pull her out and see if I can find a stamping

Test fitting the new Kohler command 22 vtwin

Nice looking tractor! I gotta say though, now that I can see the shifter gate I realize it actually is a 4-speed plus reverse 2300 series. They have a weird 1-2 shift thing, that's why that one slot is wider than the rest.

LOL, sure that doesn't have 4 forward and 1 reverse?

From seat should be


4 ---3
   N
R----2--1

That 2nd gear is a little finicky until you get use to it.  If it does in fact have a 2300.


Edit:  SWEET cast iron front end.

Also, there is a cool Idea to change out that rag joint for steering where you take the steering side of the T and bolt it to the bottom T.  On the top T you can weld a bolt and run a Universal joint off that and connect to your steering.  I wish I had seen it before I chopped mine up and did it the way I did mine.  Looks much cleaner and sturdier.

I don't usually link another tractor site, but it is good information and it is proper to credit the source.
Steering Rag Joint Replacement

That is a very cool looking tractor! I wonder who actually made it, sears or Murray

Murray.

Nice tractor, not often you see an 8hp tractor with 10 inch rims. Looking forward to seeing it progress.

You all the number were worn off off so I assumed it was 3 and always wondered why that one was longer haha thanks for the info also thanks for the info on the rag joint when I was re installing it last night I was trying to figure a way to get rid of it. Here are some I took today I have to re think the gas tank the one im using now isn't te best set up

very cool tractor, never saw one exactly like it...

So got her running now but she is definitely only running on one cyclinder Assuming it's an ignition module bc the spark plug is brand new and I just rebuilt the carb. Im going to look into it tonight after work. Im picking up a new craftsman with a 20hp kohler tomorrow for 40 bucks so worst case I'll swap that motor in.

sorry, kohler novice here. Does that have 2 coils or 1? If 2 is it one with a diode to keep the other from grounding out?

MightyRaze wrote:

sorry, kohler novice here.  Does that have 2 coils or 1?  If 2 is it one with a diode to keep the other from grounding out?

It has the two coils and the smart spark box, the coils are the ones with two wires coming out of them.

I got got lucky and found a Kohler twin with the single post ignition coils at the yard so got the motor running on both cyclinders now. So I'm really limited on space for the engine pully what do you guys think about basically running a 1:1 between the engine and gearbox than a 5 :3 from gearbox to trans ? Oh and I found a Jeep steering shaft I was going to use on my s10 with a universal joint I'm going to cut that down and use it

Sounds like a good plan!

Heres some updated picks it's coming along I need to figure out a better gas tank


EDIT MightyRaze: Duplicate image posting.

I don't see room under the hood for a gas tank.  Maybe you could put one under the seat.

Crazy_Carl wrote:

I don't see room under the hood for a gas tank.  Maybe you could put one under the seat.

That's exactly what I did, I monted the seat on a hindge and the gas tank in the space under there. I'm still debating moving the battery under the seat because I think I could get a bigger tank under the hood

That’s a fantastic looking tractor. I really like it!