[RustyCannon]

My TYM T353 HST has just short of 500 hours on it. It has the Mitsubishi S4L2 engine.

While operating it, the engine will just shut off suddenly. It will then start right back up. It would do this about every 3-4 hours, usually when I was working it clearing snow or grading our road. I suspected the seat safety switch. Now the problem has started happening every few minutes while operating the tractor, so the thing has become useless. Still suspecting the seat switch, I bypassed it. That isn't the problem, as the engine continues to die suddenly when it is at operating temperature.

I can hear the clack from the fuel solenoid when it happens. Sometimes, when the tractor is idling, the "Check" light will come on and go off, but in monitoring the dash while operating the tractor, there are no warning lights or indications that anything is wrong prior to hearing the fuel solenoid clack and the engine dying.

The only thing I've been able to find on the "Check" light is that it indicates an unsafe condition, but it doesn't outline what an unsafe condition is.

Any ideas?

 

[RC Wells]

I suspect you have triggered the error by bypassing the seat switch. Remove the bypass and change your fuel and air filters. If that does not solve the problem have it scanned by the dealer.

I believe that is a tier 4 engine, so scanning for error codes will save a lot of grief.

 

[RustyCannon]

I suspect you have triggered the error by bypassing the seat switch. Remove the bypass and change your fuel and air filters. If that does not solve the problem have it scanned by the dealer.

I believe that is a tier 4 engine, so scanning for error codes will save a lot of grief.

Thanks for your response! Yes, putting a permanent "closed" on the seat switch did nothing to affect the symptoms, so that will be put back to normal.

The dealer is 100 miles away and I have no way to get it in. They did respond to my email this morning. The service manager suspects an oil pressure switch and said that low viscosity oil might cause the trouble. I'll ask him about scanning for errors. Thanks for that suggestion.

I'm unclear as to how the fuel filter or air filter would cause the fuel shut-off solenoid to activate. Are there some safety circuits monitoring air and fuel flow?

 

[RC Wells]

If that has the Bosch licensed hybrid injection pump, fuel restrictions can cause it to overheat and shut down. A few times and the pump will need to be repaired. The Tyms I have seen come with an Asian copy of the Bosch VP44 hybrid injection pump.

 

[RustyCannon]

If that has the Bosch licensed hybrid injection pump, fuel restrictions can cause it to overheat and shut down. A few times and the pump will need to be repaired. The Tyms I have seen come with an Asian copy of the Bosch VP44 hybrid injection pump.

Thanks for that tip. I'll take a look at it. I know that the engine is a Mitsubishi S4L2. I have the manual for the engine.

The air cleaner elements looked clean. It could use an oil change, so that is #1 on the list when I get a chance to work on it. The fuel filter is on the list too. Thanks again for your help and I'll report back when I've solved the problem or have more information.

 

[RustyCannon]

If that has the Bosch licensed hybrid injection pump, fuel restrictions can cause it to overheat and shut down. A few times and the pump will need to be repaired. The Tyms I have seen come with an Asian copy of the Bosch VP44 hybrid injection pump.

Just FYI. I have a PDF copy of the manual for the S4L2 engine and it shows that the injector pump is a Bosch M type.

 

[RC Wells]

Your in luck, the M pump series are quite durable. Likely just a filter issue.

 

[RustyCannon]

Your in luck, the M pump series are quite durable. Likely just a filter issue.

Thanks. I'll be changing the fuel filter. Just ordered the oil pressure switch from the dealer. Their next best guess is the solenoid itself. I'm scared to ask the price of that.

 

[RC Wells]

The solenoid is easy to test with a multimeter. Once the tractor shuts down, leave the key alone with someone in the seat, then check the voltage to the solenoid. If it is at least 12.5 then you know there is still power to the solenoid circuit. Then switch to ohms and check the solenoid, if it is good the reading will be infinity. If it is bad there will be some value displayed.

If the solenoid is good, and you have power to it, the problem will be fuel related. Your repair manual will show if the tractor has a fuel transfer pump (also known as a lift pump). Most are electric now days, and if it is make sure that is running when the key is on.

But, first make sure the fuel filter(s) are good. With today's diesel those filters must be changed every hundred hours, if not sooner.

 

[RustyCannon]

The solenoid is easy to test with a multimeter. Once the tractor shuts down, leave the key alone with someone in the seat, then check the voltage to the solenoid. If it is at least 12.5 then you know there is still power to the solenoid circuit. Then switch to ohms and check the solenoid, if it is good the reading will be infinity. If it is bad there will be some value displayed.

If the solenoid is good, and you have power to it, the problem will be fuel related. Your repair manual will show if the tractor has a fuel transfer pump (also known as a lift pump). Most are electric now days, and if it is make sure that is running when the key is on.

But, first make sure the fuel filter(s) are good. With today's diesel those filters must be changed every hundred hours, if not sooner.

Thanks once again. Great information!

 

[RustyCannon]

Just to update y'all. I changed the oil pressure sw, changed the oil and filter and changed the fuel filter. Took it out with the box scraper on to clean-up some erosion in my driveway. Ran it for 20-30 minutes and *clack*, it shut down. Started it back up, tried to move it and it shut down again. Tried once more. Same thing. Let it sit for a couple hours to cool down. Started it up and backed it about 60 feet into the garage.

I ran across someone with a similar problem, same model tractor, and he cured his problem changing the fuel shut off solenoid. I'm ready to try that. If that doesn't fix it, I'll need to figure out how to get it to the dealer, 100 miles away.

 

[RustyCannon]

The solenoid is easy to test with a multimeter. Once the tractor shuts down, leave the key alone with someone in the seat, then check the voltage to the solenoid. If it is at least 12.5 then you know there is still power to the solenoid circuit. Then switch to ohms and check the solenoid, if it is good the reading will be infinity. If it is bad there will be some value displayed.

If the solenoid is good, and you have power to it, the problem will be fuel related. Your repair manual will show if the tractor has a fuel transfer pump (also known as a lift pump). Most are electric now days, and if it is make sure that is running when the key is on.

But, first make sure the fuel filter(s) are good. With today's diesel those filters must be changed every hundred hours, if not sooner.

Sounds easy enough except that I'm alone. No one to help.

 

[Guest]

You might need to buy or make alligator clip leads/adapters for your multimeter so that 2 hands are enough?

 

[RustyCannon]

You might need to buy or make alligator clip leads/adapters for your multimeter so that 2 hands are enough?

Got 'me. However, this solenoid is hardwired with a pigtail that goes to an enclosed connector. To get an electrical connection, I'd have to bare some wire. I don't like cutting into insulation.

I checked with the dealer and a new solenoid from TYM, including shipping and drop-ship charges runs around $250. The solenoid is an extremely common part available from dozens of sellers from WalMart to Amazon to several sellers on ebay. Makes me think they're a common point of failure. They run $38-$58 on-line, shipping included. I've ordered one. I'll swap it out and report if anything changes or not.

Next step is to pay to haul the thing to the dealer and pay the big bucks to have them figure it out. I wish I had more time to dedicate to troubleshooting it, but I just don't.

 

[Guest]

Yes in in end you can only do what you can do.

 

[RustyCannon]

I ordered a new shut off solenoid. Got it Friday. Saturday morning, I removed the old one and attempted to install the new one but there is a machining error with the threads and it simply wouldn't go more than a quarter turn.

I took the nut off the old one and put it on the new one and it went on but was very hard to turn.

Took the nut off the new one and put it on the old one and it went right on, as it should.

So, I've ordered another one, I'm returning this one and maybe next weekend I'll get to try this again.

In searching for the part number for the solenoid, I found some good reference material.

Engine service manual from TYM with Mitsubishi S4L and S4L2:
http://tym-mitsubishi.ru/booklets/Mitsubishi SL series ServiceManual.pdf

Parts Catalog for Tym T303/T353NH and HST
https://static1.squarespace.com/sta...1adda9a1d015/1483141153350/T303+T353+NHEU.pdf

 

[RustyCannon]

Just to catch up on this. The first solenoid I ordered took a week to get but the threads were defective and it wouldn't install. Returned it for refund and simultaneously ordered another new one. Took a week for that one to get here and when I unboxed it, there was greasy dirt in the threads as though someone had tried it and returned it for some reason. May have been just fine, but I decided to return that one without trying it. I ordered a third one and receive that one Thursday afternoon. Installed it Friday morning, but didn't have time to test the tractor.

I had a couple hours clear this afternoon, so I started it up and after a short warm-up, I started using it to take some erosion out of my driveway. Ran for about 15 minutes or so and *clunk* & shut down. I waited about 30 seconds and started it back up. My scraper blade was still down, so I pushed some road base backwards about 70 feet and it shut down again. I started it back up, raised the blade, and backed it another 100 feet or so into the garage where it sits.

The Check light started coming on intermittently after I had the tractor warmed up and working. It comes on and goes right back off but this hint must be something to do with what is shutting the solenoid off. Oil pressure switch is new, fresh oil and filter are installed. The troubleshooting sections in the operator and shop manuals have nothing about this trouble.

I'm frustrated beyond words at this point. According to the book, there are several switches that can open that circuit to cause that shut-off solenoid to shut the engine down. The two I first suspected - the seat switch and the engine oil pressure switch did not fix the problem. The engine temp has a gauge and the engine is running nice and cool according to the gauge.

 

[RustyCannon]

This tractor is a 2007 TYM T353 HST. Does anyone know what conditions can cause the "Check" light to come on while the tractor is being operated?

 

[BigT]

Hi Rusty,
Call your dealer and ask him what the check engine light may indicate. My thought on this is that your fuel supply may be marginal. It runs till it is out of fuel, but after a brief shut down the fuel replenishes somewhat and it can go again for a brief while and shut down again. If a diesel quits running usually it is not getting fuel. I would check the outlet of your fuel tank for an obstruction (piece of dirt) blocking flow. Check the fuel line/flow at the inlet to the filter. Check fuel flow at the inlet to the injection pump. It must be more than a trickle flow.

Another check to make if you can.....immediately check for voltage/power at the fuel shut-off solenoid when it quits running.

 

[RustyCannon]

Thanks for the suggestions. I have an email off to the dealer asking what the Check light can indicate, since the books don't really have that information. The fuel flow is fine until the fuel shut-off solenoid shuts it off. I've verified that and the fuel filter is fresh. The key is going to be what causes that solenoid to shut off. It's likely going to be a loose ground or a bad switch in that circuit.