Mower Deck on a 312-8

[JP56 38]

I recently purchased a 1988 312-8 w the Kohler Command 12-S engine. I was told by the seller, that it was a newer deck than what was originally on the tractor. I cannot find any number anywhere on the deck for identification. This deck appears somewhat smaller and slightly different in shape than the deck on my 1974 C100. Also the C100 has a deck adjustment/lift system that works with bars/shafts & adjustable trunions. The "newer" deck has a flat bar going from the tractor frame at the front of the deck, to the rear of the deck & is lifted near the middle of the deck by a chain. The flat bar at the rear of the deck is riding on top of a shaft which is through a set of holes on the bracket attached to the deck. There are also several sets of holes in the brackets, which I am guessing are for changing the rear height adjustment on the deck. I noticed the difference and asked the seller about the bar/shaft & trunion system on my older model, & he told me he had the bar that belongs on this one, found it and gave it to me, but I am not sure if this even belongs to this style of deck. It also does not have the linkage/adjusting rod & trunion with it.

I have 2 questions about this:

1) Shouldn't this flat bar be riding UNDER the shaft to lift the deck, as opposed to on TOP, of the shaft? (It appears that the shaft is supposed to slide along the bottom of the shaft of this shaft instead of the top of it & that is why the deck doesn't raise up, as the height adjustment appears limited by the length of the chain link that has the fastening bolt through it.)

2) Can anyone tell me where I can find a downloadable manual for deck installation/removal & adjustment for this tractor.

Any hints or help with this would be greatly appreciated.

[wrightorchid 261]

Please post a couple pics so it is easier to tell what you have.  There are lots of manuals on this site.

[gwest_ca-(File Mod) 11,033]

Picked a 1998 tractor because that was the first year they used a 12.5 Command engine and then picked a 42" side discharge deck to fit it.

Click on the pictures

If these are not correct post the model number and serial number off you tractor. Should be under the left side of the seat.

Better description of the deck. They are sized by their width of cut - not the width of the deck.

Side or rear discharge?

Two mower blades or three?

 

Garry

[JP56 38]

6 hours ago, gwest_ca said:

Picked a 1998 tractor because that was the first year they used a 12.5 Command engine and then picked a 42" side discharge deck to fit it.

Click on the pictures

If these are not correct post the model number and serial number off you tractor. Should be under the left side of the seat.

Better description of the deck. They are sized by their width of cut - not the width of the deck.

Side or rear discharge?

Two mower blades or three?

 

Garry

Gary, the pic on the second file Mower Rotary 42in SD 1998 78345 3-400 IPL.pdf Looks exactly like the deck on my 1974 C100. I have downloaded the first file shown here & will check that one. Thanks.

[JP56 38]

Here is the only info I can find on tags on the tractor so far:

Wheel Horse 312-8

Tractor ID # 2112K805 29480

Engine: Kohler 12 Magnum

Model: M12S

Spec: 471527

S/N: 1730108263

Deck: Unable to find any tag on it to identify it so far.

 

Will have to take the deck off I guess to check it more thoroughly, in case there is a tag someplace where I cannot see it while mounted on the tractor. The deck appears to have been restored with new paint and some plates welded onto it at the back where the rear wheel axle brackets are bolted to it. I am guessing that it may have been a label type tag mounted somewhere along the back & it was either damaged and removed during repair.

 

The weather has been nothing but bad here the past 3 weeks with rain & high humidity & I have no room in the garage to work on it, so I am going to have to remove the deck outside between storms, and check closer for a tag and will take some pictures of the mounting & lifting set up and attempt to post them here in the hope that someone can give me some info on the deck.

 

The 2 files attached above in this thread here both appear to be the identical deck as the one on my 1974 or 1975 (Still not sure which year it is, because I have a 74 parts manual & a 75 owners manual) C100. I am currently working on an electrical wiring problem on this one. The 2 wires on the left side attached to the Clutch Safety Switch have gotten sheared of somehow with about only 3/4 of an inch of wire left on the connector screws. Damned if I can find the rest of the 2 wires on the tractor to repair them. As I said the weather has been very much against me the past few weeks here so working on it outside has been catch as you can. One thing I noticed about the OEM wiring diagrams I have found for this tractor, all show a seat safety switch, but neither one of my 2 tractors have a seat safety switch. 

 

The numbers on this one are:

Tractor Model # L 0990 9

S/N: 47404

Engine: Kohler 10 HP

Model: K241S

S/N: 6097616

Spec: 46636D

Deck: 0542M505

 

[gwest_ca-(File Mod) 11,033]

1988 312-8 model number 21-12K805

Click on the pictures

This is the 1988 model of 42" deck for this tractor

Here is a list of the 42" side discharge decks in the order they were produced

Mower DNA

1977 model 75-42MS01 replaces RL-426, 5-1421, 5-1422, 5-1423, 5-1000, 5-1001, 5-1010, 1975 model 5-1011, 1975 model 5-1012, 1976 model 65-42MS01, 1976 model 65-42MS02 -These 42" side discharge decks all use blades with 5/8" x 3/4" double-D center hole unless the spindles have been upgraded

 

1977 model 75-42MS01 replaced by 1977 model 75-42MS02, 1978 model 85-42MS01, 1979 model 95-42MS00, 1979 model 95-42MS01, 1980 model 05-42MS01, 1981-83 model 05-42MS02, 1984 model 05-42MS03, 1985 model 05-42MS04, 1986-88 model 05-42MS05, 1989 model 15-42SC01, 1990 model 15-42SC02, 1990-92 model 15-42SC03, 1993-2007 and 2009-2012 model 78345 -  (These decks all use blades with a 3/4" center hole except 75-42MS01 unless it has been upgraded)

 

When looking at parts lists for these keep in mind many on-line lists and those we have identified by TIPL (Toro illustrated parts list) are shared with the 48" deck so the illustration may be for either deck. That does not help to identify a deck model. If we have an original manual as the one above the illustration should be correct.

 

 

1974 C-100 8-Speed model 1-0390

The 9 at the end is not used but if you subtract 5 from that 6th digit you get the model year. 9-5=4=1974. You will find a 6th digit on the attachments at the time also.

Perhaps the deck 05-42MS05 came originally on the 312-8 and is now on the C-100.

Not uncommon for a dealer to sell a new tractor with an older deck if that is what he had in stock. Makes them hard to identify but the universality of the design means we have no shortage of decks - yet.

 

Garry

[JP56 38]

Good morning Gary. Thanks for the files. I have downloaded them and will start going thru them, but at first glance they appear to be files I already had. Made some room in the garage yesterday and spent all day tracing the wiring on my 74 and finally got that running again.

I also put the 88 up on ramps and messed with the deck. While I still don't think it's correct, I did manage to get the deck up higher so that it shouldn't scalp my lawn anymore by putting the rod in the top hole and over the raising bar at the back, but won't know until I get a chance to test it. I did take some pics & am going to try to upload them from my phone so everyone can see my problem. I found 3 tags that were either painted over or were removed before painting. The one that shows white was where I tried to get the paint off to see if it was readable.

I just realized that I didn't mention, the deck on the 88 has a round bar attached to brackets on both ends of the deck at the front for lifting. Also I noticed that the rear center wheel bracket appears to be a home made bastardization as you can see the part that was cut and welded, combined with a steel patch at the right rear wheel attaching point, and if I try putting the wheels into the lowest position, the top of the bracket hits the back of the deck housing and would still need to go another 3/8 of an inch before the lever could lock into the notch to hold the adjustment. I think the deck is either much older or later then the tractor. I have never come across a deck with the round lift bar at the front before. Most of the files you posted all show the flat or square type bar stock with holes and pins for the lifting mechanisms, which is the same as what is on my 1974 and was also on my old 1971. 

 

[gwest_ca-(File Mod) 11,033]

I went back through the models and this is the first one that I came to. Its is the last of that design. Click on the picture and download from that page.

Garry

[JP56 38]

I pulled the deck completely off. I found he had 2 lengths of chain bolted together that went from the lift rod arm down to the deck bar. That length attached to the adjustable eye bolt on the lift rod arm was 4 links long, the length on the deck was 5 links long, and when he bolted them together, he bolted 4 links on each together and left the fifth on dangling. He also gave me a lift rod that looks identical to the one on my 74, that goes into the frame near & under the seat and it has 2 holes in it where it would go over the deck and a little further towards the front end of the rod is a pin that would go into a hole or slot on a different deck I am guessing. I am thinking that he made one deck from parts of several because I am finding too many things that just don't seem to belong, like the wheel height adjustment. I cannot set them into the lowest position because the bracket for the center wheel hits the deck and it would need another 3/8" of travel space in order for the height adjusting lever to lock into that slot. Then I look at that same axle, and it is against the rear of the deck in the center, but the 2 mounting brackets on the ends of the axle that attach the axle to the deck appear to be home made or something. They just don't look right. I am downloading the file you just sent now. I will check it out & maybe I will take and post some picks of the deck so you can see what I am talking about. I am not sure if I will ever get this deck onto this tractor so it will be adjustable. Thanks!

 

According to the download file, I have part #24 the mower support, but need parts #25 Lift rod, #27 nut, #28 Lift St, and can probably use parts # 35 & 36 Leveler & nut, IF I can locate them. Also parts 73, 74 don't look the same as what is on the deck now, and part 38 on my deck looks home made according to the parts picture you sent me. I am guessing the angle he welded them on is off by the 3/8" I would need to put the wheels at lowest setting, not that I would ever cut that low anyway.

Thanks again for the great info and all your help.

Edited August 9, 2018 by JP56

[JP56 38]

 

So, after looking at the parts list and then searching at Toro, it appears that I may not be able to use this deck with this tractor with out some modifications including welding, which I don't/can't do myself. For one thing the leveler in the front interferes with the deck drive belt, which explains why it was put thru the support arm assembly with nuts, instead of threaded thru the tab on the arm where it's supposed to go. I don't think the lift arm on this 312 will work with the lift rod for the older  deck.

 

[Tankman 3,518]

Can't seem to hit the footrests with the rubber stabilizing bumpers ('90 520-8)..

I "think" previous owner replaced the chain. How long should the chain be?