JD 997Z mower problem

[9973720wb19]

since this is a JD forum, maybe you guys could help with my JD 997 Z mower. I have had an intermittent problem since day one...6/08. The safty feature will not allow the mower to start without park break on...fine. However, sometimes, after I start it (break on) then go to put the break down/off...the engine stalls. I took it to the dealer and they said they could not make this happen. I just did my spring tune and I had this issue one out of five fine starts.

Any advise or information that would help in talking to my dealer?

Thanks

 

[Henri88]

You might have a safety switch in your seat. If you shift your weight for a split second off your seat while trying to disengage your parking brake, that would kill the engine.

 

[Jeepin4fun]

I agree with Henri. Are you a smaller guy and your mechanic is not? Your seat switch is most likely the culprit. Lift the seat up and make sure the sensor is in the correct seated position and is not loose. If it is and you continue to have a problem, I'd get a new seat switch. Only other thing I could think of is crud in the connectors. Clean the connectors on the seat switch as well as the row of relays right under the hood behind the seat.

 

[9973720wb19]

thanks guys. I purchased a new switch today and took off the seat but could not find where it goes. I see it on line, but all I saw was a wire that went directly into the seat cushion and I did not want to mess with that. So, cleaned the plugs and reset the added seat suspension option to less suspension...put back together and it's working for now so we'll see.

I'm much lighter than my service guy, and I'm hoping it was the added seat suspension option. I had it set to give the most flex. Now it does not give when I sit on it.

 

[newt92]

since this is a JD forum, maybe you guys could help with my JD 997 Z mower. I have had an intermittent problem since day one...6/08. The safty feature will not allow the mower to start without park break on...fine. However, sometimes, after I start it (break on) then go to put the break down/off...the engine stalls. I took it to the dealer and they said they could not make this happen. I just did my spring tune and I had this issue one out of five fine starts.

Any advise or information that would help in talking to my dealer?

Thanks

Make sure the steering sticks are all the way out when you remove the P-brake.

 

[Tlday]

I have a 997Z with the same issue. My mower worked for three years with no issues. One day it started acting up when I would release the brake. I bypassed the seat safety switch to see if that is the problem. Same thing. I let it set all last winter and this spring it worked perfectly for about five startups. Back to doing the same thing. I can't find a problem anywhere.

 

[Bheal]

I would check the safety switches that are behind the seat. Also could be a problem with the seat detecting the weight of the person on it. Check the wires under the seat to make sure they have proper connection and aren't damaged.

 

[Tlday]

I would check the safety switches that are behind the seat. Also could be a problem with the seat detecting the weight of the person on it. Check the wires under the seat to make sure they have proper connection and aren't damaged.

I think I may be onto something. I checked all of that switch issue a hundred times before giving up. I adjusted the linkage to the hydraulic drive unit from the control arms. I noticed that the mower was trying to creep forward when the brake was released and the control arms in the stop position. While adjusting the rods, the mower kept shutting off. Once I got the wheels to stop and the linkage arms tightened properly, the mower seemed to be working as it should. I won't know for sure until it sets for a few hours. Thanks for the input.

 

[9973720wb19]

I think I may be onto something. I checked all of that switch issue a hundred times before giving up. I adjusted the linkage to the hydraulic drive unit from the control arms. I noticed that the mower was trying to creep forward when the brake was released and the control arms in the stop position. While adjusting the rods, the mower kept shutting off. Once I got the wheels to stop and the linkage arms tightened properly, the mower seemed to be working as it should. I won't know for sure until it sets for a few hours. Thanks for the input.

hello from the OP here - i like this approach - replacing the safety switch does not help - ask me how i know.

 

[Tlday]

hello from the OP here - i like this approach - replacing the safety switch does not help - ask me how i know.

Well, I let it set for a couple of hours and tried it again. I'm still getting the same problem. However, it appears that it is better than it was. I have noticed that sometimes turning the ignition to off briefly and then turning it back on will coax it to keep running. Whatever the problem is, it is causing me to really hate this mower.

 

[9973720wb19]

Well, I let it set for a couple of hours and tried it again. I'm still getting the same problem. However, it appears that it is better than it was. I have noticed that sometimes turning the ignition to off briefly and then turning it back on will coax it to keep running. Whatever the problem is, it is causing me to really hate this mower.

I know! When mine was new, I took it back to the Dealer and they said "we tried all day to make it do what you said and it worked fine for us"....ahhhh! Now each time it stalls/happens, I wonder is this the time I will not be able to get it going? the only thing I've been able to do, and i'm not sure it helps but I do get going. is when it starts to stall (because it thinks either i) no one is in the seat or ii) the break is still on...as I move the arms in...I quickly put them back into neural position keeping the engine running - then move them back out very very slow...it seems to be a bit of a work-a-round. Oh, forgot to mention, let down the park break very very slow as well. so that's...park break down slow and arms out slow. and smooth for both. WHAT A PAIN!

 

[fuel doctor]

since this is a JD forum, maybe you guys could help with my JD 997 Z mower. I have had an intermittent problem since day one...6/08. The safty feature will not allow the mower to start without park break on...fine. However, sometimes, after I start it (break on) then go to put the break down/off...the engine stalls. I took it to the dealer and they said they could not make this happen. I just did my spring tune and I had this issue one out of five fine starts.

Any advise or information that would help in talking to my dealer?

Thanks

There is a switch along the relays the best I remember it is a switch that when you bounce up & down on the seat on rough ground it keep the mower going. But if you remain up for more then a second or to it will kill the mower

 

[Tlday]

I know! When mine was new, I took it back to the Dealer and they said "we tried all day to make it do what you said and it worked fine for us"....ahhhh! Now each time it stalls/happens, I wonder is this the time I will not be able to get it going? the only thing I've been able to do, and i'm not sure it helps but I do get going. is when it starts to stall (because it thinks either i) no one is in the seat or ii) the break is still on...as I move the arms in...I quickly put them back into neural position keeping the engine running - then move them back out very very slow...it seems to be a bit of a work-a-round. Oh, forgot to mention, let down the park break very very slow as well. so that's...park break down slow and arms out slow. and smooth for both. WHAT A PAIN!

I worked on it again yesterday, taking the brake safety switch out and cleaning it. The contacts looked good. I did a continuity check on it and it seems to be switching off and on as it should. I have also noticed that sometimes if I just let the mower run for a few minutes after starting it up, it will work fine (sometimes). I'm beginning to suspect that the pressure switch on the pump might be the problem. Once it takes off, it will usually run fine the rest of the day. I might as well give up. This mower is an electrical nightmare.

 

[Tlday]

since this is a JD forum, maybe you guys could help with my JD 997 Z mower. I have had an intermittent problem since day one...6/08. The safty feature will not allow the mower to start without park break on...fine. However, sometimes, after I start it (break on) then go to put the break down/off...the engine stalls. I took it to the dealer and they said they could not make this happen. I just did my spring tune and I had this issue one out of five fine starts.

Any advise or information that would help in talking to my dealer?

Thanks

OK. Problem solved. I had to take it to the dealer to get it fixed. The problem was a faulty seat delay module located on the engine firewall.