New to me 312-8

[KAA 1973 71]

Hi Guys,

Thanks for letting me onboard 

Recently acquires this 312-8, she's a 1989 vintage but still in decent shape

Back story, about 10 years ago my brother's friend asked him to go check out this tractor. Owner says it's down on power

after rebuilding the engine, his friend passed on it but my brother decides it's an easy fix, he's really sharp with small engines, he's a machinist by trade.

Takes it home and pulls the head off and sees the bore is nice and shiny. Pulled the side cover, crank and rod, measures it up and decides 

on new rings and a hone job.

Good as new.

Friend ends up buying it off him, uses it for a few years and bought a new mower. It sat for a few more years, (unfortunately outside), he tries to fire it 

up and comes to the conclusion it needs a fuel pump. Replaces the pump, still no fuel, it sets for another year until he drops it off at my brothers shop. I asked him about it a few weeks ago and he said the guy would probably sell it, at this point I know nothing about Wheel Horse tractors. Before I decide to buy it I wanted to figure out what exactly is going on.

Previous owner said no fuel and he thinks the lobe is worn off the cam. I take the brand new fuel pump off and we figure out he installed it upside down so the arm on the pump is nowhere near the cam lobe.

Made him an offer and he takes it.

 

Decide on just freshening up the tractor, I'm finding it really hard to not go with a full resto but she's going to be put to work so I don't see the necessity of being really pretty.

First thing is to replace the fuel line, filter and get the fuel system plumbed up.

Previous owner removed the entire air cleaner assembly and lost it, acquired the parts, although delayed in shipping.

Rear end seals are leaking, ordered the seals, they were also delayed in shipping but finally arrived last week.

 

A few weeks ago I drained the rear end fluid and filled with Kerosene, ran the tractor off an auxiliary tank since it will be sitting for another 4 months before I drag it home, unfortunately tractor only ran for 5 minutes and dies. Ended up taking the carb off and running it through the ultrasonic cleaner for an hour and ordered a carb kit, which is currently stuck in Indy at the post office.

Continued on the rear end, drained the K1 and left empty until I replace the seals.

 

Last weekend I tackled the seals, not the easiest job when it's totally assembled but got it done and glad I decided to do it brake shaft seal was leaking bad, forgot to mention earlier before I bought it I pulled the trans dipstick and there was no oil on it, that was my deciding factor to replace the seals.

BTW, I ordered one of those seal pullers of f Amazon, totally worthless, seals ore too small. Used screwdriver and picks.

This one

https://www.amazon.com/gp/product/B000FPYW4K/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

 

Finished that up sooner than I thought and decided to mount the new rear Ags.

I bought the narrower ones, I have very limited space in my shed, currently it houses a  Toro 5060 Timecutter and Agri-Fab vac trailer which is what will be the Horse's primary duty, along with pulling a roller and dethatching rake.

When I get it home in the spring it'll get a thorough cleaning, it's killing me to work on it while it's this dirty.

 

Can anyone give me some insight on why in the world the brake pedal is back so far at rest? it's so far that it's bending the running board, we looked at it 

for about an hour to see if there was something bent but everything looks normal. The only way I can see getting it vertical is replacing the return spring, it

is under tension until the brake is in the position you see here, that or drilling a hole to relocate the spring closer to the pivot to minimize the pull tension.

 

Thanks for listening to the ramble, hope to get it buttoned up next week while I'm off, this was kind of a side project and I've got bigger projects to finish up.

[oliver2-44 9,785]

The 312-8 are great tractors. They can do anything you ask of them, and sip fuel doing it. I always enjoy find dates on the rims, kind of a little time capsule.  my 1985 312-8 has the dates stamped into the rims.  That tractor will clean up nicely.  Give the tins a wax job and it will look great.

[oldlineman 1,481]

As far as the brake peddle I believe the foot pan is the stop for the brake peddle. There is a tap that is probably bent down where it pivots , bend that up with a crescent wrench and all is well. I also have a 1990 312-H good tractor

Edited December 22, 2020 by oldlineman

[Maxwell-8 4,277]

 in tha club my friend!

 

Got a 312-8 myself, see you are also getting in the hobby hard and fast!

[ebinmaine 67,748]

 

All the tractors around our acreage are a lot older so I can't really help you much with questions but as said above you've gotten a hold of a great machine.

Smooth running. Heavy duty. Easy to maintain.

 

Any parts you need it's a good idea to give a shout here and see who has what where...

 

I understand your logic with not wanting to do a full restoration on it but there's nothing wrong with doing a bunch of prettying before you need to use it. 

 

My go-to tractor is a 1974 c160 that's been fully restored. 

[Pollack Pete 2,273]

Great tractors those 312-8's.I have 5 or 6 of them.One with a rear discharge deck is my favorite go-to tractor.Your's looks to be in really decent shape.Little tinkering and it will be close to 100%.Have fun with your new toy.

[Maxwell-8 4,277]

6 hours ago, KAA 1973 said:

Can anyone give me some insight on why in the world the brake pedal is back so far at rest? it's so far that it's bending the running board, we looked at it 

for about an hour to see if there was something bent but everything looks normal. The only way I can see getting it vertical is replacing the return spring, it

is under tension until the brake is in the position you see here, that or drilling a hole to relocate the spring closer to the pivot to minimize the pull tension.

 

 

I will take a look as fast as i can to mine (2days) , something rod has to be to long. probably not OEM

[lynnmor 7,317]

You should pull the fuel tank and rinse it out, also inspect the petcock screen and rubber bushing.  You can see the screen using a flashlight and looking in the gas fill hole.  I say this because you are doing the carburetor and other fuel system parts so just clean up the whole system.  While the tank is off there will be plenty of cleaning and painting to do to prevent rust.

[JCM 9,215]

My favorite tractor among them all ,basically trouble free since 1989. First picture taken in 89 second one last year. Good luck with it and     to   

[MAWHguy2019 21]

I have a 312-8 as well. This machine is, as the kids say, "the bomb". While I cannot answer your specific question, I can tell you that this machine will be a true workhorse for you. Enjoy!

[KAA 1973 71]

You are correct about the brake pedal, my foot rest is bent down a ton but I thought it was because the brake was malfunctioning.

I'll straighten it out the next time I'm down there and hopefully some of these slow parts shipments will arrive.

 

Just want to add that all the incredible knowledge here makes working on these tractors a breeze.

You guys are top notch, really.

Fantastic forum here.

[KAA 1973 71]

Edit

After an enormous amount of searching and reading  think I've figured out some of the wiring, I still have 6 wires and the wiring schematic shows 4  

 

 

Well I spent a few hours on the 312 this weekend and had an epic fail.

One of my PTO safety switches was broken and I had to wiggle the the PTO arm to get it to start, decided to just replace all the switches, (including the parking brake one since it's the same style), I 

didn't take a picture of the switch wiring  since I left everything plugged in until the new switches arrived.

Swapped the wiring over to the new parts and installed and now I have a no start issue.

Somehow the wiring is not correct.

I've combed through the all the wiring schematics here and I have a few issues with them.

1) The purple wire coming from the clutch switch to the PTO switch is not purple, mine is pink. Has anyone discovered variables in the wiring colors?

      I substituted the pink for purple and it seems like that is correct.

 

2) I do have an "extra" purple wire coming out of the harness but is is far too short to connect to the PTO switches and the purple wire, (mine is pink),that should connect to the PTO is coming from the 

clutch switch. Can anyone tell me where that should go?

 

What is the purpose of the 2 switches as opposed to one? When I push the lever forward I hear one turn on the the other when I push it further.

Edit- Found a post explaining

The seat switch is there to shut down the engine if the half of the PTO Switch that connects to it is in the PTO ON position and no one is in the seat, if your PTO is OFF the seat switch will do nothing. The dark blue wire form the PTO switch will join the wire going to your magneto.

The other half of the PTO Switch will prevent the starter from operating if the PTO is ON, if your PTO is OFF the switch will do nothing. If you have a clutch switch the purple wire from this half of the PTO switch will go to the clutch switch, if you don't have a clutch switch it will go directly to the small terminal on the Solenoid. You don't have an engine low oil switch so the low oil relay is not going to be used.

The drawing below should be helpful. Both switches have wires that would go to the "idiot lights" for Seat and PTO (not shown on the 310 drawing) but you don't need them, just cut them off.

 

If anyone has a close up picture with the PTO switch wiring I would really appreciate it if you can post it up.

I guess I need to start by knowing which switch should be on top/bottom.

We don't have internet at the shop so it was not possible to look up diagrams while I was there, I printed off the schematics and will take them with me next weekend.

I usually take pictures before I tear things apart but I literally waited to get the new switched before I pulled the wires.

The wiring harness has been modified, I can see crimped connectors but it's not anything drastic.

Edited February 8, 2021 by KAA 1973

[chrisjb 8]

This is the orientation mine was mounted.  So it looks like the orange and blue with the plug should be on the other switch than as pictured above.

 

Also, do you have the 2 little papers in between the switches and the switch and base?

 

The top switch had wires junctioned from them.

Edited February 11, 2021 by chrisjb

[chrisjb 8]

This is what I mean by junctioned off

 

Note the wires going under the battery tray (the junctioned wires)  I think one is solid purple and the other is black or purple with a white stripe on it.

[KAA 1973 71]

Well I was combing through my phone and did manage to find a picture, don't recall taking it.

I do have the plastic pieces between the switches, I didn't disassemble anything until I received the new switches.

Thanks for the pictures, between yours and mine I believe I have it figured out.

I knew the wires were junctioned off, didn't recall which ones.

 

Still, I don't see any purple wires with the exception of the one that is too short to go to the PTO switches.

Even the wire in your picture that I assume is coming from the clutch switch looks pink to me, just like mine.

 

 

[KAA 1973 71]

Made some progress on the 312 last week, finally got it running after chasing a no start issue that turned out to be a bad spark plug, it had spark 

jumping from the threads to ground but would not make spark on the electrode. Changed the plug and it fired right up. Weird.

Working on it  I didn’t like that the hood is really wobbly.

After a bit of research I found on here where a guy added the Chevy door bushings so

I decided to go that route. After disassembly of the hood I found the pin that attaches the hood is

really worn so I decided to replace it, making my own at my brothers’ machine shop.

I wanted a bit more durability so I decided on stainless steel for the material.

The only readily available material I found was either at McMaster or Amazon, both places

were really expensive for a 24” piece, (each pin is 7” long). There was a guy on an auction site selling bar

ends, (this is the material that is held by a machine that will be too short to make additional parts),

10 pieces for the same price as the other places, I figured since I was already setting up the machine I

would make a few extra since I don’t really have another use for the material.

Also purchased stainless steel E clips.

I have the extra parts for sale here.

 

 

Thanks!

Keith