Does 29hp Kawasaki DFI Watercooled have problems

Mike_S · Jul 6, 2008

As in an earlier posting, this engine has a serious problem in that after using the Toro ZMaster which it powers is used for mowing for about 45 minutes, the fuel filter empties of fuel and the engine dies. Let it sit for 5-15 minutes (depending upon its mood) and it starts back up as good as new and then that repeats all day long. The fuel tank selector valve and fuel pump have been replaced. I have tried leaving the fuel tank caps loose as well as extra tight and the dying issue also happens with both tanks. This problem started at 52 hours on the hour meter, the dealer needs 2-3 weeks of wait time until they can get to it and another possible week to get parts if they can figure out what parts.

I contacted Kawasaki customer service for that line of engines and was told, apologetically, that they could not help me due to contractual obligations with Toro.

I am wondering if the 29hp Kaw water-cooled DFI engine is generally a trouble-prone engine or has a history of having a particular issue and is otherwise dependable -- the downtime is a killer and dependability is needed and I need to decide if I need to trade it for a different brand.

Thoughts, opinions, experiences with this engine since it is used on several brands of ZTR's besides Toros?

Thanks,

MikeSp

shot_gun · Jul 6, 2008

Mike, we have a JD797 with the same engine. 1800 hour and no fuel problems. the only major problem with the motor is when the ACR contraption on the cam came apart and took out the govenor gear. Replaced the cam, govenor and waterpump while we were in there. DFI has an electric fuel pump that supplies the fuel to the fuel injectors. Is the fuel pump still running when the engine stalls? Have you blown back through the lines going into the tank? On our JD there is a little screen on the end of the suction line that goes in the tank. Thankfully our JD only has one tank to worry about.

You could always setup a nurse tank too and see if runs for a while with out starving for fuel.

shot_gun · Jul 6, 2008

Just read your op. Did you change the air filter right before it happened? just curious.

Mike_S · Jul 7, 2008

shot_gun said:
Just read your op. Did you change the air filter right before it happened? just curious.

At 52 hours and not mowing in dusty conditions, I have had no reason to change the air filter... yet.

Mike

Mike_S · Jul 7, 2008

shot_gun said:
Mike, we have a JD797 with the same engine. 1800 hour and no fuel problems. the only major problem with the motor is when the ACR contraption on the cam came apart and took out the govenor gear. Replaced the cam, govenor and waterpump while we were in there. DFI has an electric fuel pump that supplies the fuel to the fuel injectors. Is the fuel pump still running when the engine stalls? Have you blown back through the lines going into the tank? On our JD there is a little screen on the end of the suction line that goes in the tank. Thankfully our JD only has one tank to worry about. You could always setup a nurse tank too and see if runs for a while with out starving for fuel.

The fuel pump shuts down when the engine stalls (remember that it has been replaced). When the key is turned to the "prime the pump" position, the pump whines as usual and fills up the fuel filter -- but when the engine is starved for fuel, the fuel pump is HOT and even though the fuel pump fills the fuel filter, the fuel empties immpediately--usually bubbling as though it were boiling. Ten minutes later, the fuel pump will fill the fuel filter and it will start up and fun fine. I cannot help but wonder if it is the DFI controller that is having a senior moment--even at 52 hours.

Thanks for your observations -- will blow back the lines, but it is pretty unlikely as careful as I am about fueling both tanks that both tanks would be clogged and act in the same manner (but not impossible).

Mike

Mike_S · Jul 7, 2008

shot_gun said:
Mike, we have a JD797 with the same engine. 1800 hour and no fuel problems. the only major problem with the motor is when the ACR contraption on the cam came apart and took out the govenor gear. Replaced the cam, govenor and waterpump while we were in there. DFI has an electric fuel pump that supplies the fuel to the fuel injectors. Is the fuel pump still running when the engine stalls? Have you blown back through the lines going into the tank? On our JD there is a little screen on the end of the suction line that goes in the tank. Thankfully our JD only has one tank to worry about. You could always setup a nurse tank too and see if runs for a while with out starving for fuel.

Shot gun--just curious, have you used ethanol-blended gasoline in your JD797 with that same Kaw engine? I ask because it ran great last year and starting January 1st of this year, Missouri became the third state to require 10% ethanol content of ALL unleaded fuels and I am thinking that my engine may be having a good ole case of vaporlock (takes me back to cars I owned in the 1960's...YIKES!!!) It is too coincidental that the fuel problems started with the first fueling of 10% ethanol blend (which I did not know since the law does not require such blending be posted...grrrr)

I am wondering if ethanol blends will vaporlock easier than straight gasoline.

Mike

shot_gun · Jul 7, 2008

Yes the gas we get here is blended. I'm not sure what the % is. As far as being careful on filling the tank thats not what I'm woried about. New tanks if they arnen't carefully cleaned at the factory you end up with plastic shards that get sucked up and stick to the intake screen. I checked our fuel pump after it runs a while you can't touch it. It's pretty warm. It sounds like there is a sensor problem telling the fuel pump to shut down. I didn't see any thermal switch to shut off the fuel pump. I guess vapor lock is possible... where is the fuel pump located on the machine?

Does the machine start right back up after it stalls? I was thinking you could instead of blowing back through the lines pull them out of the tank and check the ends of the lines for stuff. I'm pretty sure they use top draw on them.

On the air filter I was thinking that if you switched it maybey you got the wrong one but i thought about it that was only for the carb units and the new machines all use HD donaldson filters

Mike_S · Jul 7, 2008

shot_gun said:
Yes the gas we get here is blended. I'm not sure what the % is. As far as being careful on filling the tank thats not what I'm woried about. New tanks if they arnen't carefully cleaned at the factory you end up with plastic shards that get sucked up and stick to the intake screen. I checked our fuel pump after it runs a while you can't touch it. It's pretty warm. It sounds like there is a sensor problem telling the fuel pump to shut down. I didn't see any thermal switch to shut off the fuel pump. I guess vapor lock is possible... where is the fuel pump located on the machine?

Does the machine start right back up after it stalls? I was thinking you could instead of blowing back through the lines pull them out of the tank and check the ends of the lines for stuff. I'm pretty sure they use top draw on them.

On the air filter I was thinking that if you switched it maybey you got the wrong one but i thought about it that was only for the carb units and the new machines all use HD donaldson filters

The fuel pump is located just to the left of the seat behind the fuel filter and fuel tank selector valve -- easy to see and easy to get to.

The engine will not start up immediately after a stall -- the fuel pump attempt to fill the filter, but the filter empties as fast as the fuel enters it. After a 10 minute wait, it starts immediately and runs fine for another 30-45 minutes.

It sounds like a good idea to check for the plastic shards (sometimes such things are NOT cleaned out like the aluminum millings that were left in the transmission housing of my first JD 4400HST tractor which destroyed the hydraulics, hydrostatic tranny, brakes, etc.).

It is interesting that you are using blended gasoline. I found a Toro "Master" service center today that was glad to chase down the problem even though I did not purchase the ZTR from them -- eventually they ended up with some conversations not only with Toro tech support wondering about the blended fuel and vaporlock but Kawasaki stating that mine was the 6th such incident with that engine and that they were sending out a new fuel pump that was designed to solve the problem of vaporlock -- that the fix was a Kawasaki engine part number and not a Toro part number. At least there is now hope!!

Thanks for your suggestions,

Mike

shot_gun · Jul 8, 2008

Good deal! We've had our since april 2003 with no fuel problems. It sounds like you've got it under control now good luck.

ray66v · Jul 8, 2008

Mike_S said:
the fuel pump is HOT and even though the fuel pump fills the fuel filter, the fuel empties immpediately--usually bubbling as though it were boiling. Ten minutes later, the fuel pump will fill the fuel filter and it will start up and fun fine.
Mike

This is an obvious clue. A good test would have been to use freon, co2 or water to cool the pump and see it it "cured" the problem.

Sounds like your nightmare is almost over.