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Scott99
10-06-2002, 05:07 PM
Anyone out there have any experience with the John Deere SST? I recently purchased the SST18 and really like it. I got a really good deal and it fits my mowing needs perfectly. I have no problems operating it but I wanted to know if anyone has any information regarding the reliability of this machine or anything else I might need to be concerned about. I have searched the web and there is not much info out there on the SST. The few discussions groups I have looked into really don't have any first hand experience with these. Any help would be appreciated.

Scott

aussiemow
07-10-2003, 01:40 AM
Im in Australia ( Melbourne) I purchased an SST16 eighteen months ago , the only real problem I have with it is the zero turn leaving skid marks on any slightly damp areas and the cost of blades.

bigdaddyspags
08-16-2004, 09:49 AM
Any new input for this thread?

NorrisG
08-16-2004, 10:27 AM
I bought one back in 2001 with the mulch kit. It has been a very reliable mower, I've had no problems with it mechanically. It will not hold a hill at all. It would be a very good mower for a homeowner with a fairly flat yard. For myself, I should have spent the little bit extra and bought a commercial ZTR mower. :cry:

mowhigh
08-24-2004, 08:29 PM
Terrible on any kind of slope. Has been discontinued, so good pricing is available on existing inventory.

BPCHAMLEE
04-14-2006, 06:06 AM
I am looking at a used JD SST-16. Does anyone know what these sold for new before they were discontinued, so I have a frame of reference for price? Thanks-Bill

NorrisG
04-14-2006, 09:45 AM
Brand new in '01 I paid $4200 for mine. 42" cut and included the mulch kit.

ccecilm
04-15-2006, 08:51 AM
Finally! I was beginning to think that I was the only person in the world that bought one of these.

I bought an SST16 in 1992; 42C deck w/7 bu. bagger and recycler plug.

Mowhigh is right on about being terrible on hills. In 1993 I got a rear weight kit [80#] to help with that problem and it does so long as the grass is dry. I just do yearly maintenance like change oil, oil filter, air filter, spark plugs & vacuum filters. Repairs I have had to do: Replace gas tank [2nd year] and Replace steering actuators [this year]. I would suggest that you purchase a Tech Manual for the machine because they are fairly complicated to work on and JD dealer shop labor is very pricey [at least in my area, it is $90K per hour].

BPCHAMLEE, a new machine sold for around $4K. A used one in good condition is now around $2K.

sst16YUK
09-02-2007, 02:28 PM
No ccecilm, you are not the only poor sucker who bought this machine.
I bought mine (SST16) new in 2001 for $4500.00. I am mowing 3 acres with it & haven't had much in the way of trouble until this year, aside from the hill mowing problem.
Mine wont steer very well at all. The local shop wasn't much help ."..maybe your engine is bad." was the response after a phone call to them! I perform the same annual maintenance you do. I replaced the vacuum filters with very little results. The John Deere site of course says to consult my local dealer for the tech manual or call the 1800 #.

Is there an online source for the tech manual, maybe PDF format?

I believe my problem lies with the steering actuators/switches or in the vacuum lines.

ccecilm
09-03-2007, 11:42 AM
sst16YUK,
I do not know of an online tech manual but I do have one on CD. Steering actuators were the source of my "loss of steering" problem. They are very easy to replace once you get down to them. Contact me personally for info on how to obtain a tech CD ( cecil.mckinney@sbcglobal.net )

sst16YUK
09-04-2007, 09:55 PM
Thanks Cecil,

My steering went out completely yesterday. I'm thinking its my steering actuators also. Was your local JD dealer much help? Mine seems big on selling you parts & service but not on technical assistance. I'll be contacting you.

David

ccecilm
09-26-2007, 07:04 AM
Call the JD Parts Resource Center @ 1-800-522-7448. Tell them you want the SST16 or SST18 Technical Manual on CD, both machines are covered in the same manual. Have your machine's serial number handy because there
are different publications for 2 different serial number ranges. The cost is $40.00 + S&H.

jeffwoehrle
06-08-2008, 10:32 AM
New to forum with my first post.

My steering switches failed as well on my SST18. Turns out the switches themselves weren't bad, but the rubber boots had hardened. (Was also a problem I noted in cold weather prior to total failure.)

I trimmed the boot from the switch 2 years ago and it's been fine since. I don't mow in wet grass, so there isn't much chance of the switches getting wet (as the boots would be to protect). Seems to have solved the problem.

As a side note, the battery charging capability on my SST has given out. New battery, but still no charge. When voltage gets down to around 5, steering quits...first in reverse, then forward as well.

Would this be a simple replacement of the module on the right side of the engine, or something internal?

Much appreciated.

Jeff

ccecilm
06-09-2008, 08:43 AM
Jeff,
Thanks for posting the info about the rubber boot on the steering switches.

I can't offer anything about your charging problem other than diagnose the charging system. You may very well need a tech manual for that (see post above).

jeffwoehrle
06-11-2008, 04:56 PM
Found out that the voltage regulator module is toast. New one about seventy bucks (cheaper two-wire model won't work). The three wires on this JD/Briggs model must have something to do with the loss of steering power? Well, maybe.

New part will be on tomorrow. I'll post any additional issues.

ccecilm
06-12-2008, 07:04 AM
Let's hope the volt reg is the proble.m The forward/reverse actuators are activated by 12volt signal from the steering switches. These darn machines have too many interconnected parts for my small brain!

gordym
06-18-2008, 11:32 AM
Unfortanetly my SST16's steering has been acting up too much lately. I have a friend who bought his within a couple of months of when I purchased mine and his steering is having problems also.......
My steering appears to work but after I change from reverse to moving forward..... the steering goes out completely! After a min. or so of driving slowly, it begins to come back and is able to make tighter turns. Once I pop it in reverse, the steering disappears and I am stuck again.
I am thinking about replacing the switches that others are talking about but my confusion is.... my thought process tells me that a switch is either bad or good. I've had my wife drive while I manually engage the switches (with the aid of a long handle screw driver) and I get no change on how rapidly the steering re-engages to turn moving forward. I'm going to order the switches and springs from a local Deere dealer for about $70 and see if that helps but I will be suprised if it helps. Everyone here seems really helpful so I thought I'd stop by and see if there are other ideas.
I really have to fix this one because my wife is stubborn and when she cuts the grass, I tell her not to put it into reverse but she doesn't listen (are you suprised lol) and when she gets in a tight spot after reverse.......she plows forward with reckless abandon. I know she is going to crash forward into something and of course....... it will be my fault. TABOL
Once I figure out my issues, I can help my friend.

Thanks ahead of time to all here!

ccecilm
06-22-2008, 06:32 AM
gordym,

Some thoughts:

1. There may be a poor electrical wire connection between forward/reverse solenoids and ground causing both actuators to work against each other.

2. Dirt and/or lack of lubrication at steering pedal pivot points.

3. Weakened steering pedal return springs.

sst16YUK
06-30-2008, 09:15 AM
Hi everyone,

I have a SST16. Sorry I never posted the fix for my mower, here goes...

I found the problem to my steering was the vacuum line. I had 5 psig of
vacuum at my steering actuators tee & 15 psig vacuum just after the check valve at the engine. After following the line I found 2 sizable holes in it just past the engine compartment. The steering worked like a champ with a new line.
This line leads from the engine back underneath the console on the left side. It is difficult to see (my mower had grass clippings hiding it). I removed the seat deck to follow the line, be sure to unplug the seat safety switch & reconnect when re-installing the seat deck.

ccecilm
06-30-2008, 09:33 AM
Thanks sst16YUK. Bad vacuum line is about the second biggest cause of steering loss next to the propel switch and/or steering actuator failure that I have heard of. A vacuum test is one of the checks to perform in the troubleshooting procedure set forth in the tech manual. I always go through the electrical checks first then proceed to the vacuum test. Thanks for posting your fix.

gordym
07-06-2008, 06:53 PM
gordym,

Some thoughts:

1. There may be a poor electrical wire connection between forward/reverse solenoids and ground causing both actuators to work against each other.

2. Dirt and/or lack of lubrication at steering pedal pivot points.

3. Weakened steering pedal return springs.

Well, I replaced both steering switches and springs.
I made sure to mark the switch position with a Sharpie to make sure they were in the same place when I put it back together.
I fired it up and I turned the steering wheel to the right and the SST shot in the left direction!!!!!

Reverse is working fine........ forward is now worse than before.:hammerhead:

gordym
07-06-2008, 07:08 PM
Well, I replaced both steering switches and springs.
I made sure to mark the switch position with a Sharpie to make sure they were in the same place when I put it back together.
I fired it up and I turned the steering wheel to the right and the SST shot in the left direction!!!!!
I tried adjusting the switches in both directions and it seemed a little better but occasionally when I start from a dead stop and turn the wheel
to eiter the left or the right, it goes the opposite direction. There is no way I could have wired it wrong due to wire lengths and I made a drawing of connections prior to disconnecting. It is intermittent and it still takes a while in the forward direction to get the steering to work at all.
Revers is still fine though................

Reverse is working fine........ forward is now worse than before.:hammerhead:

I'll take a look at the vacuume lines next but the SST works fine in reverse.
I feel dumb as a tree stump.

Sorry for the repost but the site wouldn't allow changes after 10 mins.

jeffwoehrle
07-07-2008, 05:32 AM
"...it still takes a while in the forward direction to get the steering to work at all."

I think that may be a clue. Vacuum line issue seems like a fair bet.

On the bright side, you will be an expert by the time you work through this!

:dizzy:

ccecilm
07-07-2008, 08:22 AM
New switches and springs may require re-adjusting rather than just marking where old switches were. Make sure you have the propel switches set to the proper clearance.

Microswitch/Propel Switch Adjustment (from the tech manual):

1. Park machine safely with park brake locked. See “Park
Machine Safely” on page 3.

2. Locate the proper switch through the sight windows (A)
in the side frame. The right wheel may require removal from
the machine.

3. If adjusting the top switch, fully depress the forward
pedal 2 or 3 times and let the pedal return to neutral on its
own. If adjusting the bottom switch, fully depress the
reverse pedal 2 or 3 times and let the pedal return to
neutral on its own.

4. Loosen the appropriate nut (B) holding the switch to the
side of the frame.

5. Adjust the switch bracket location with the tabs to set the
gap (0.040“) between the switch’s metal plunger and the lever
associated with the switch.

6. Tighten the nut holding the switch while holding the
switch bracket stationary.

7. Check the switch gap plunger. Repeat as necessary.
With the switches adjusted properly, a slight “click” (switch
closing) can be heard almost immediately when depressing
the foot pedals.

gordym
07-11-2008, 09:18 AM
Thank you all for your help with my SST woes. It has helped me tremendously has saved me a bunch of money and hassle. I used ccecilm's instructions and tunrs in the proper direction now. I still have the original steering problem but my next "iinexpensive" attempt will be to bypass the vacume lines and see what affet that has on the steering.

I will keep you posted...............

ccecilm
07-12-2008, 07:30 AM
Great! At least one problem is solved. Bypassing the OEM vacuum line is a good idea (and inexpensive). If you need to measure vacuum run engine at medium idle for 3 - 5 minutes to bring engine to normal operating temperature. Vacuum at engine should be 13 inches. Here is the whole shabang from the tech manual:

1. Run engine at medium idle for 3 - 5 minutes to bring
engine to normal operating temperature.

2. Park machine safely with park brake locked. See “Park
Machine Safely” on page 3.

3. Raise hood.

4. Disconnect vacuum line (A) and install tee fitting into the
line.

5. Connect the vacuum gauge the third connector of the
tee fitting.

• If vacuum is 33 cm (13 in.) of mercury movement or
greater, vacuum supply from engine is ok. If a steering problem remains, check vacuum f ilters, and solenoids at actuators.
• If vacuum is less than 33 cm (13 in.) of mercury
movement, retest vacuum using straight fitting connected
directly from the engine to the vacuum gauge.
• If vacuum is 33 cm (13 in.) of water movement or
greater, vacuum supply from engine is ok. If a steering
problem remains, check vacuum filters, and solenoids at
actuators.
• If vacuum supply from engine is ok, remove fender
deck and test for vacuum at the tee fitting (G) near the
actuators. Disconnect one actuator hose and test for
vacuum.
• If the vacuum is within specification, the lines are
good.

CEWall
07-19-2008, 08:42 PM
Well first, Hello to all fellow SSTrs that at times may Love to hate their SST's.

I have had mine since October 2001 and all in all I love it. Yes a big z would be nice but I have a "happy" bond with my SST16.

Well till today when the Steering went out completely. Like others I have had come and go steering gremlins but nothing that a good cleaning of the steering switches would not address. Today it was "100% casters up"

Just got done reading the posts in this thread and what a gold mine of great information. Thanks to all that have and do share. With Deere no longer making these I have found few of the JD mechanics really understand them.

First Thank-You, Thank-You, Thank-You for the information about the Tech Manual. Early on I had asked my dealer about one and was told it was not available to the general public due to the "proprietary steering technology". Hey gotta give my dealer a A+ for creativity with that one. I will be calling JD on Monday.

For those of you that have the Tech Manual, does it do a good job of showing you how to get to some of these parts?????
I am a handy person but the location of some parts and the complexity that seems to be involved in getting to them is amazing.

Based on a New (2 months) yet Dead battery when I went to start mowing today (jumped it). I have a strong feeling my steering issue may be tied to an electrical issue. Possibly the voltage regulator module. I have the battery on a charger now. Will see if I get steering back, order up a tech manual and go from there.......

True Life Experiences and Sharing are Great Teachers!

Best To All,
Topher

p.s For those with a slope to deal with and a bagger system. I have found that if I mow all the flat areas first, the added weight of the full bags helps with traction on the slopes........

ccecilm
07-20-2008, 09:02 AM
"For those of you that have the Tech Manual, does it do a good job of showing you how to get to some of these parts?????"

Yes it does. Sometimes the "take apart to get down to it" is described in another section but that's because the writer assumes you have been to JD Tech College.

CEWall
07-20-2008, 04:22 PM
Perfect..........

Thanks for the confirmation ccecilm! :cool2:

FYI....... With a fully charged battery, steering worked just fine today. Once I can track down why my "new" battery is draining so fast I should be set for now.

Looking forward to getting the Tech Manual and having a roadmap to help diagnose issues.

Thanks Again C. Wall

ccecilm
07-20-2008, 06:15 PM
CEWall,
The battery drain is most likely the voltage regulator. I believe jeffwoehrle had a similar issue on page 2 of this link.

Don't get intimidated by the volume of information in the manual (I was because I am not hydraulically or electrically inclined).

jeffwoehrle
07-21-2008, 05:33 AM
Hey all,

The voltage regulator replacement solved my draining battery issue, but I still need to jump to start...even right after shutting the engine down. Battery tests okay, but not enough oomph to turn it over.

Steering problem is gone, but that seemed to appear as the battery (same one as now) drained due to lack of charging.

Unsure if the lack of cranking ability is part of the same issue, or perhaps a malfunctioning compression release.

Short on time for the next week or two to mess with it, and using the starter/charger for starting isn't that much of a problem for the moment.

I'll post further steps I take.

weeleen2
09-17-2008, 11:57 AM
does anyone have any advice on where i can purchase a bagger for my mower. mike

gordym
04-19-2009, 03:22 PM
Great! At least one problem is solved. Bypassing the OEM vacuum line is a good idea (and inexpensive). If you need to measure vacuum run engine at medium idle for 3 - 5 minutes to bring engine to normal operating temperature. Vacuum at engine should be 13 inches. Here is the whole shabang from the tech manual:

1. Run engine at medium idle for 3 - 5 minutes to bring
engine to normal operating temperature.

2. Park machine safely with park brake locked. See “Park
Machine Safely” on page 3.

3. Raise hood.

4. Disconnect vacuum line (A) and install tee fitting into the
line.

5. Connect the vacuum gauge the third connector of the
tee fitting.

• If vacuum is 33 cm (13 in.) of mercury movement or
greater, vacuum supply from engine is ok. If a steering problem remains, check vacuum f ilters, and solenoids at actuators.
• If vacuum is less than 33 cm (13 in.) of mercury
movement, retest vacuum using straight fitting connected
directly from the engine to the vacuum gauge.
• If vacuum is 33 cm (13 in.) of water movement or
greater, vacuum supply from engine is ok. If a steering
problem remains, check vacuum filters, and solenoids at
actuators.
• If vacuum supply from engine is ok, remove fender
deck and test for vacuum at the tee fitting (G) near the
actuators. Disconnect one actuator hose and test for
vacuum.
• If the vacuum is within specification, the lines are
good.

Well, now that the weather is warming up and the snow is gone....... I'd like to try and fix my steering problem again.
I charged the battery up over the last few days and my SST 16 works fine in reverse but will not turn when moving in the forward direction.

Does anyone have a diagram showing the above procedure so I can try an "bypass" the vacuum lines to see if that is the problem. It sure seems weird that the tractor works fine in reverse)
I don't have a "T" connector or vacuum tester tool for the 13 psi.

Any ideas and help would be appreciated because I'm laid off and don't have the cash to have someone charge me $500 to pick up my tractor....unless I have to............

Thanks for everyone's help!!!

Johnagain
04-22-2009, 01:47 AM
I just got done working on my uncles SST16 and had to change the actuator on one side because it would not steer in foward. This is the first thing I would check on your mower. Remove the back portion of the mower the part with the seat. and then you can get to the actuators easily. Remove them and check them carefully for any cracks in the rubber. If it has any then replace because this is where the vacuum leak is. Here is the part # from JD AM133406. Cost is $74.20 If you go to the JD website you can View all the technical manuals online for this mower. You can also order the part and they will ship it to your local dealer. If you need any further assistance let me know and I'll try to help.

gordym
04-22-2009, 10:10 AM
I just got done working on my uncles SST16 and had to change the actuator on one side because it would not steer in foward. This is the first thing I would check on your mower. Remove the back portion of the mower the part with the seat. and then you can get to the actuators easily. Remove them and check them carefully for any cracks in the rubber. If it has any then replace because this is where the vacuum leak is. Here is the part # from JD AM133406. Cost is $74.20 If you go to the JD website you can View all the technical manuals online for this mower. You can also order the part and they will ship it to your local dealer. If you need any further assistance let me know and I'll try to help.

Thanks for the help Johnagain!

Do you remember if it was the left or right actuator that was causing your forward steering issues? I've had that area pulled apart when I replaced the steering switches last year and remember that there were two of them under the seating area. I'm just assuming that one is forward and one is reverse so any additional insight into what I may be looking for is tremendously helpful.

Thanks again for the help as I hope to try this today and see if I can find a crack in the actuators.

gordym
04-22-2009, 12:58 PM
OK, I've been playing with the steering actuators and here is what I found:

I swapped the electrical signaling wires going from the left and right actuators and now it steers fine going forward but when I depress the reverse pedal I get no turning.
This leads me to believe that the vacuum pressure is fine and the actuators are working properly............ unless I am totally fubar'd.

There seems to be some internal confusion between the forward/reverse electrical signaling............

Help!!!!

gordym
04-22-2009, 03:17 PM
OK......OK.......
After hours of farting around with the parts and swapping wires, checking voltages, checking vacuum lines..........
I found a couple of REALLY tiny pinholes on the right actuator.
I stuck my finger over a couple and "manually pushed the plunger and I was able
to make it work going in the forward direction.

I'm going to call one of the local JD Dealers and order one.

I'll keep you posted............................

Johnagain
04-22-2009, 08:54 PM
I'm glad you found the problem. When I found the problem with the one side and looked at it closely I decided that I would replace both of them because they are the some age and I figured that the other one would start leaking air very soon. When I got is out I pulled on it and found lots of dry weather cracks in it so it wouldn't have been long until it broke also. When you get the part in at the dealer check it over carefully as one of the new parts I got was defective. The part came apart in my hands when I tried to install it. The two pieces that hold the rubber together weren't glued together very well and seperated.

The routing of the vacuum lines on the actuator might be different on the new ones when you get them. All you do is install the line from the tee section on the mower to the inlet in the center of the actuator and then remove the filter from the old one that is at the very end of the plumbing and install that on the inlet that is on the outer edge of that actuator. Good luck!

gordym
05-03-2009, 11:37 PM
I replaced the actuator and everything is working GREAT!!!!!!!!

I love having steering again.

Johnagain
05-03-2009, 11:40 PM
Glad you got it going again.

BruceDK
08-18-2009, 03:29 PM
Steering in reverse stopped suddenly on my SST after mowing some tall weeds. Thanks to your site I got some clues where to look. Lo and behold one of the plugs behind the right rear axle was dangling loose. Plugged it back in and away I went! :cool2:

ktaugher
08-29-2009, 09:08 PM
Thanks to everyone for posting!

Lost steering response on my SST-16, forward and reverse, due to a bad voltage regulator. This is a Briggs & Stratton part (by the way, B&S no. 394890, JD No. LG691185 (which my local dealer had) but note that the JD website says that "LB691185 has been replaced by MIU12514" $92 on 28 August 2009. Ebay for $50.

If you're getting a steering problem concurrent with a dead battery, I'd consider testing and/or just replacing the voltage regulator. I suspect it's a chronic problem, because my JD dealer's parts mgr. said he had them in stock before I even finished reading him the part number.

5 minute job, the voltage regulator is bolted to the right side of the engine shroud, just behind the right cylinder. It's a square aluminum block, with a pair of yellow wires and one red wire coming out of a block of expoxy potting compound.

Symptoms:
My battery was intermittently going dead, I thought it might have been the ignition switch not going completely off. I started taking the key out, to make sure my knee wasn't turning it partially on when I climbed out of the seat. This 'seemed' (ha ha) to work until a few days ago.

It wouldn't start, so I had to jump start it, and after about 45 minutes of mowing the steering stopped responding. I let it sit for a few minutes with the engine running, and the steering came back to life for about 60 seconds, enough time to get it in the shed, but not to park it.

I went on line and found this forum, and saw voltage regulator, vacuum leak, or bad switches as possible culprits. Since I had the battery charging problem, I got the voltage regulator first. The steering has to have electricity to actuate the hydraulic system.

This morning I replaced the regulator, hooked up a 4 amp charger to the battery, and let it sit for about 4 hours. Then I tried it, it started right up, and steering was as good as new.

Hope this helps someone else out.

namosi
06-06-2010, 05:19 PM
Hope this helps someone else out.

it even helped a SST16-owner in Germany. :germanflag:

Thank you guys!

ccecilm
06-07-2010, 08:06 AM
Thank you for posting your experience. I'm sure it will help others in the future since people that have troubleshooting knowledge on the SST are pretty scarce.

ccecilm
06-09-2010, 08:46 AM
How did you go about testing the voltage regulator or did you just put on a new one without testing the old one? Please reply, I need to know because I may have the same problem but hate to just start throwing new parts at it.

ccecilm
06-09-2010, 03:58 PM
Never mind, I found it:

If you have a volt=ohm meter, you can check the voltage of the battery with the engine off.

Then start the engine, and recheck voltage. If voltage hasn't increased to about 13.5 to 14 volts, charging system needs to be checked.

You can check the the stator voltage by unplugging the connector that comes from the engine that connects to the regulator. Set you meter to AC volts, start engine and run at full speed, voltage should be about 20 volts AC. If it's not, then the stator is bad. If you have 20+ volts AC then stator is ok.

Voltage regulator/rectifier can be checked by reconnecting stator and running engine full speed and checking voltage at the orange wire and the yellow wires. You should have 13+ volts DC at each wire, if you do not, replace regulator/rectifier.

ccecilm
06-09-2010, 06:09 PM
Well, the above is certainly NOT correct for my SST16; It has 2 yellow wires coming from the stator and 1 (one) red wire coming out of the regulator/rectifier.

The previous post may apply to the SST18 but I can not confirm because I do not have one.

Shifty937
05-02-2011, 03:43 AM
Well I happened to stumble upon this thread and lots of good advise here on the SST. Thx everybody, anyhow this past weekend I went to go look at an JD XL172 about an hour away. Pulled into the drive and a guy was loading it up and the guy said I just sold it. Very disgruntled to put it mildly, I let him know I wasnt happy. So the guy says tell ya what, I do have another JD riding mower if your interested. Im like yeah ok, so went to his garage pulled of the tarp and low and behold a SST18 with missing hood non the less in nice condition with 400 hours runs exelent. Guy says $200 bucks its yours ill deliver it for $20. Feel like a thief, but hey...... :usflag: :hammerhead: Same price as the XL172 which needed quite a bit more work to the deck and some other things.

So now im a proud owner one these Deere's, my question is that it seems so slow. Like the pedals are binding up in the linkage and are hard to push and hold and if I push to hard at just past half pedal the motor cuts out and wants to die unless I let off, in forward or reverse. Also think it is having the very same charging issue that seems to be a big problem on this thread.

I notice it has a shock attached to the linkage, and the pedals dont return fully to there neutral position. I busted out the the can of PB BLaster soaked it down before work to return with the same problem. Is there some kind of adjusting it may need ? Yes the steering works great. Until just bit ago no steer in reverse. Please help, my grandma could out walk this thing. Anybody have a complete hood assembly also ? Also need a seat.

YBNORMAL
10-21-2012, 09:26 PM
New user here, I thought I would post some thoughts about my SST16. As you all know there is not to much information out there about how these things work.

The information in this thread has been great, and to add to it:

The way this thing works is that as soon as you touch the forward or reverse pedal, the switches in the back tell the tractor which actuator to collapse. The actuators do not control the steering per se, they just position the mechanical linkage so that the wheels turn properly based on forward or rearward movement of the tractor.

For example:

lets say you are making a slow left turn moving forward, (for simplicities sake) the tractor would be moving counterclockwise as viewed from above.

Low lets say you are making the same slow left turn but in reverse, The tractor should rotate in a clockwise direction from above.

Without its compound linkage the tractor would steer like any other tractor in forward, but the wheel would have to be reversed in order to make the SST behave like a normal steering tractor in reverse (left turn in reverse makes the tractor rotate clockwise on any other tractor with steerable front wheels but the SSt front end would go left when backing up with its wheel to the left). People already didn't like how the SST steering felt, imagine if they would have left out the compensating linkage :laugh:

You will notice this linkage is hooked to the trans in the same place that the bolt is, that adjusts the straight line tracking of the tractor (the relationship of one axle speed to the other.)

You can watch the linkage do it's thing if you have the fenders off, put the tractor in park, key off:

1:turn the wheel left or right, the linkage going back to the tranny will not (should not) move yet since the actuators have not been told to set up for forward or reverse.

Now, simulate a pedal input (actuator movement) by taking the part of the linkage that the actuators are connected to and move it to the right of the tractor (I believe this to be the "forward driving actuator" but I am not sure, my motor is blown and I am waiting for another :)). While holding the actuators to the right side of the arc, turn the steering wheel to the right, now you will see the linkage going back to the trans pulls forward, likewise a left turn on the wheel will move the trans link back.

2:Now push the actuators to the left of the arc, and again turn the wheel to the right, now the linkage moves the trans lever back, likewise a left steering imput moves the trans link forward.

This linkage essentially takes the place of what your brain would be doing on a standard zero turn that has levers that you push forward to go straight, right lever forward to make a forward left turn and right lever back to make forward right turn, or any combination of the above to make the zero turn do what you want.

A standard zero turn has a direct link to each side of the trans for both steering and forward/back motion control, simple really, steering is done by your brain adjusting wheel speed left to right. The SST has a forward/back lever on the left of the trans right near the actuator switches that is mechanically linked to the forward back pedals. While at the same time it has another mechanical link that controls the relative wheel speed left and right wheel.

My SST would zero turn in reverse all day long, but I had to be on the forward pedal pretty hard to get it to start steering in forward, at that high of a speed, it would not "zero" turn on a dime but would turn at normal mowing speed. I was able to get buy, but it was annoying. I was not real sure what was doing what under there till I read this thread and put some things together in my head while looking under the hood of mine. Waiting for my new-ish motor :).

I found that the switch tabs on my SST16 had bent slightly (probably from the pivot points not being lubed well, or grass wedged in there), and I could not get a setting on the forward switch per the advice in this thread.

So I got that all squared away, also the last time I had the fender deck off when I bought the thing two seasons ago, I sprayed the actuator bellows with WD40 after reading what little info was out there, saying that they get brittle and crack then wont hold vacume. I am happy to report that mine are still nice and soft and I hit them again with some spray lube to keep them supple.

I hope I explained clearly so that other can understand the voo-doo of the SST16. It really is not very complicated once you know how things work on these tractors.

YB

YBNORMAL
10-21-2012, 10:19 PM
So now im a proud owner one these Deere's, my question is that it seems so slow. Like the pedals are binding up in the linkage and are hard to push and hold and if I push to hard at just past half pedal the motor cuts out and wants to die unless I let off, in forward or reverse. Also think it is having the very same charging issue that seems to be a big problem on this thread.

I notice it has a shock attached to the linkage, and the pedals dont return fully to there neutral position. I busted out the the can of PB BLaster soaked it down before work to return with the same problem. Is there some kind of adjusting it may need ? Yes the steering works great. Until just bit ago no steer in reverse. Please help, my grandma could out walk this thing. Anybody have a complete hood assembly also ? Also need a seat.

As far as the speed thing goes, I had a similar problem and found that the main belt for the tractor was out of adjustment. The parking brake pedal does two things, it puts slack in the belt so the engine cant turn the trans pulleys. The second thing it does is physically lock the trans with another linkage running back the left side of the frame.

There is a tensioner attached right after the park pedal, so when the parking brake is off it is sprung and keeps tension on the belt. It only has a certain amount of throw in order to keep the belt tensioned. I thought my belt was stretched too much, BUT, there is another idler pulley that you can move fore or aft in order to get the belt tensioner in it's range of motion. It is a plastic pulley if I remember correctly and it sits just about right in the middle of the tractor and has a metal tab that keeps the slacked out belt on, it's shaped like a "V".

I would start there for the speed issue. The linkage for the pedals is not real complicated. The forward pedal linkage is not adjustable, it will throw as far as that "shock" you were talking about will let it. BUT, if the reverse pedal is not right it will not let the forward linkage go all the way. When it is right, the forward linkage will bottom out the shock, the reverse pedal linkage will be a little loose. When hitting reverse, the throw at the trans is very small and the linkage will actually bow if you push too hard on the pedal. If you try to adjust the bow out of the reverse rod, you will start to limit the travel of the forward pedal. Thats how mine was anyway. Try lubing the pivot of the pedals, That helped mine quite a bit.

I don't know why the engine would die mid pedal like that, sounds more like an engine problem than a linkage or tractor problem.

YB

teegee60510
05-18-2013, 11:37 PM
I've read through this thread and it seems to have good information so I hope someone can help. I have my SST18 and suddenly it stopped while cutting the lawn. It won't move forward or reverse, only right or left. I took the fenders off and cleaned it up, lots of grass clippings in there. I ordered the Tech Manual but it won't arrive until Friday. I'm thinking either the belt is loose or the clutch is shot. Any thoughts?

Thanks