Jump to content
Sign in to follow this  
OneWithWaves

312-8 Won't start; dim seat switch light

Recommended Posts

Hello everyone,


Sorry to make an account and post for help right away, but I plan on sticking around for a while. Anyway, I'm having a hard time getting my 312-8 tractor to start. It's got a Kohler Magnum 12 engine and the ID under the seat is 2112K806 (space) 37223. A few weeks ago it decided it didn't want to start; when the key was turned to the run position, the seat switch light was dim or flickering very faintly. I assumed the switch was dead, as it didn't have a distinct "click" when it was pressed any more and the tractor is approaching about 30 years of age.

I just got a replacement seat switch from Toro and installed it, but the tractor still refuses to start. The first few times, the seat switch appeared to be working correctly but the tractor insisted the clutch wasn't pushed in, according to the dash lights. I came back a few minutes later and the tractor still refuses to start, although now the seat switch light is behaving as it did before. If I leave the key in the run position and get off the seat, the light works correctly and lights up brightly and solidly, but sitting back down causes it to pulse and light dimly again. I've tried engaging and disengaging the PTO clutch, which the dash reports correctly, as well as the regular clutch, which also seems to respond correctly now.

I'm hoping you fine folks might be able to help me, as the tractor is going to get sold if I don't get it running and it's quite important to me. Any and all help is greatly appreciated, and I thank you in advance for your help!

Share this post


Link to post
Share on other sites

check the motor oil level

there are 3 safety switch's that will keep the tractors from starting if the key switch is good
PTO lever switch
clutch pedal depress switch
oil level switch
also check 25amp fuse

Brian

Share this post


Link to post
Share on other sites

Thanks for the advice, Brian!

This probably comes off as a stupid question, but where would I find the 25 amp fuse? My original manuals are long lost by the previous owner and the only fuse I see is one that's clipped to the battery tray; it looks like a regular automotive fuse and it looks good to me. I believe the oil level should be fine but I'm sure it needs to be changed very badly - where would I find the drain for the oil, and what viscosity should I replace it with?

Share this post


Link to post
Share on other sites

Here is a good detailed wiring diagram. Each circuit has it's own diagram.
http://www.wheelhorseforum.com/files/file/1862-tractor-1989-312-8-wiring-detailed-492-4509pdf/

Is the problem the starter won't engage and run to crank the motor over or
No ignition so motor won't run.

There are 2 pto switches.
One controls the starter along with the clutch pedal switch and the low oil relay.

The 2nd pto switch controls the ignition along with the seat switch.

There is a chance you have bad grounds. May be worth while to remove and clean them up.

Garry

Here is the 1989 operator manual
http://www.wheelhorseforum.com/files/file/2021-tractor-1989-300-series-8-speed-om-wiringpdf/

Kohler operator manual
http://www.wheelhorseforum.com/files/file/4107-engine-kohler-magnum-m-8-m12-m16-om-tp-2200-fpdf/

Garry

  • Like 1

Share this post


Link to post
Share on other sites

Thanks for the diagrams and advice, Garry!

I think you're probably right about the grounds being bad. I just got the tractor to start and it ran great - once it was running, the seat switch was working perfectly, killing the engine when I stood up with the PTO clutch engaged, but once I parked it again and attempted to start it, it went back to looking like the circuit is bad. I can see the wires coming from the seat switch and know the black one is the ground, but I can't find where it is grounded to the chassis as the cluster disappears under the instrument panel. I was wondering if anyone knows where the seat switch is grounded on this model or has an idea based on other models as I'm at a loss for where to look.

I also forgot to add - the ignition works fine; my issue is the tractor refusing to run the starter motor when I turn the key to the start position.

Edited by OneWithWaves

Share this post


Link to post
Share on other sites

use a jumper wire from the + battery terminal to the 1/4 blade terminal on the starter solenoid  to check if the solenoid is good you can also jump a cross the large terminals on the starter solenoid
this should make the starter motor run to check that

Brian

Share this post


Link to post
Share on other sites

Hi everyone,

Sorry for disappearing for a week but I haven't had the opportunity to put some more work into this tractor until today. It took me an embarrassingly long time to find the seat switch ground, which was bundled with many of the other grounds on a terminal connecting to the battery's ground. I took these grounds apart and cleaned up the connectors with some light sandpaper; the years of service had definitely done a number on some of them. I put the whole thing back together and got the starter to crank for one attempt, which got me excited (the tractor starts reliably, but only if it gets about three shots with the starter motor), but then the symptoms from the beginning of this thread cropped up again. Now, I'm not sure if maybe I missed another ground wire somewhere or if it could be a problem with the solenoid, as Brian's mentioned. It just seems strange that the dim seat switch light could be a symptom of a bad solenoid. Anyway, I found it on the tractor but it seems a little different than most of the solenoids I've seen (and I'll admit I haven't seen too many before). It looks like it only has two terminals and a ground, and from my understanding there are generally 3 or 4 terminals with a ground. I've included a picture of this solenoid - would I still test this one as Brian suggested or is there something different about this one?

Thanks for all your help this far!

IMG_20150730_120358.thumb.jpg.899d3f38ac

PS When you look at the photo, notice the ground isn't actually grounded to the frame of the tractor, but a small ground wire connects it to the bundle of grounds I mentioned earlier in this post.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By WingfieldWheelHorse
      Howdy Folks,
       
      I am hoping one of you knowledgeable lot will be able to help me out. I am fixing, as a surprise for my father, the ignition (that he took apart initially!) on our Wheel Horse 312-8. As we are in the UK we have struggled to get the ignition and loom which would have made this slightly easier. as the previous loom had melted slightly and a few wires came 'melted together'. And it is here where my problem lies. I have managed to get an ignition from a reputable provider here in the UK, but failed to get the loom. After visiting various local dealers they recommended I just connect the wires using spade connectors. 
      From images of the ignition prior, I have been able to connect most of the wires into the new ignition with ease however where some of the wires were twisted and burned together I am struggling to work out which wires go to the remaining terminals. I have found various manuals (most helpful one attached) and think I have followed them well. However I am left over with a small red wire of which I am unsure as to where it goes.
      The three wires I was left with were: a white wire, a large red wire, and a small red wire. I know that the small red one but join either the big red or the white but I am unsure.
      What I would have ideally is someone being able to send across a photo to ensure that I can't get this wrong or to be able to say definitively where it joins. Furthermore if you can see any basic errors you feel I may have made an help on that would be graciously accepted. 
      This is my first post but as I try to fix more and more parts it certainly won't be my last!
      Hope you can help gang!
       
      B
       
      ***This is all the info I have on the mower:
      Toro 312 - 8 Cast Iron Kohler 12 HP Engine
      42" side discharge
      Manufactured circa 88/89
       
      Vin/Model No: 78346
      Serial Number: 3900161
      Parts & Service Manual - E1 12K802/ R1-12 K01 8 Speed ***
       
       






    • By DennisThornton
      But this one caught my attention!  I just don't think this is safe!
       
      From HomemadeTools.net
      https://s3-us-west-1.amazonaws.com/hmt-forum/sparks_flying.gif
       

       
       
    • By John Casadonte
      I have a late 90's 269H with the Kohler 17HP motor.  After cutting for about 1 hour I turned it off, tried to start it about 10 minutes late and it would not crank.  The dash lights turn on (oil, battery, parking brake), I can hear/feel the relay click but the starter will not turn.
      All fuses checked All relays checked no broken/frayed wires  
      Solenoid will not engage when crossing the terminals with a screw driver and key switch in on position.  Is this a defacto solenoid issue or do I need to check other things?  Also, I am showing that the part number for the solenoid is: 52-435-02.  i found one at http://www.milfordpower.com/R12130-Starter-Solenoid-Replaces-Kohler-52-435-02S-p/r12130.htm
       
      Thanks in advance for any direction or advice.
       
      John
    • By Team70R
      Two of my 606's both have battery trays and electric start. Both with factory 606 tags. Now my question is why not just get a 656 from the dealer ship? Was it cheaper to get a 606 and upgrade the starter? Both have the proper key ignition switches as well. 
    • By Mastiffman
      Hello gang,
       
       Have a question about this model as I have an opportunity to purchase a used one in god shape for $425 delivered.

       It has 632hr on it and the infamous run and then shut off. Which I'm guessing is the Ignition Voltage Regulator under the flywheel being that it's a common problem with these Onan Engine and the amount of grass and garbage that collects under there in that area. Seller states that the "engine runs strong and tight"... The unit is NOT a Hydro but is an 8 speed and looks to be a good condition. Has new Deck Spindles and Blades with grease fittings. It comes with a 50" deck. I currently have a 1988 Belt Driven 52" Scag walk behind with a Kawasaki v420 engine with a slight knock it. But it's been that way since I got it about 8 years ago... 

       With the work involved in the repair and the price is this 416-8 tractor with the time and money? Especially not being a Hydro... Should I just wait to find a good deal on a Hydro or get this one as I can always resell it... I like the Hydraulic setup of the H series as well as the slightly wider stance in the front end...
       
       I've Attached some Photos. I haven't seen this unit in person ad the gentlemen selling me the unit is going to be driving 15-20 miles to drop if off.
       
       There are a couple Hydros in the area but they are asking $1200-$1750...
       
       Thoughts and experience?
       
       Thanks.
       
       Andrew C. 






×