A year ago I noticed that my 743 (natural aspirated diesel) Would choke out after about an hour of hard work. I sounded like it was starving for fuel, so I put a new mechanical fuel pump in it and thought the problem was solved. I only used it for short jobs and not at full throttle until now. The symptoms now are:
Pointing up hill it runs good
When I point downhill it seems to lose 350-500 RPM
Pointing downhill it will eventually choke out. It feels like it is starving for fuel, but the exhaust is black smoke, like I am over fueling it.
Once it chokes out and dies, I wait for 5 minutes and restart it. If I have to continue pointing down hill, it may stall 3-4 more times. If I can swing it around and and point it uphill, it takes about 2 minutes to "clear up", then the RPMs and power come back.
A mechanical oil pressure gauge shows 40 psi at elevated RPMs, but at idle it shows 20 psi. 20 is just above the RED zone and the GREEN zone starts at 40 psi. It is in the white zone 95% of the time.
The hours meter shows 550 hours and has always worked since I got the machine. The former owners used it to clean 2 horse stalls twice a month, so I kinda believe the meter.
Where do I look?? Air and fuel filters have about 30 hours on them.
Pointing up hill it runs good
When I point downhill it seems to lose 350-500 RPM
Pointing downhill it will eventually choke out. It feels like it is starving for fuel, but the exhaust is black smoke, like I am over fueling it.
Once it chokes out and dies, I wait for 5 minutes and restart it. If I have to continue pointing down hill, it may stall 3-4 more times. If I can swing it around and and point it uphill, it takes about 2 minutes to "clear up", then the RPMs and power come back.
A mechanical oil pressure gauge shows 40 psi at elevated RPMs, but at idle it shows 20 psi. 20 is just above the RED zone and the GREEN zone starts at 40 psi. It is in the white zone 95% of the time.
The hours meter shows 550 hours and has always worked since I got the machine. The former owners used it to clean 2 horse stalls twice a month, so I kinda believe the meter.
Where do I look?? Air and fuel filters have about 30 hours on them.