Bobcat 753 keeps losing power

[ProudMarineDad]

I have a 753 w/2600+hrs. Changed fuel filter today, purged fuel lines of air. Idles fine. Has full tank of fuel. At 3/4 throttle and a little load of pushing brush it begins to lose rpm's and engine almost dies. When i stop it will come back to full rpm's and do it again when i move forward. Is it fuel pump? Tank problems? Where do i start? Also i get one beep on display and battery symbol is highlighted. battery is good. Don't understand. Any help appreciated. thanks

 

[DowneyC&E]

Did your problems start before or after the fuel filter change?

 

[shane]

Could be a clogged fuel pickup. If your fuel primer bulb collapses, that's probably it. Also if your fuel shutoff lever on the injection pump is not within a hair's width of the stop in the run position that could be it, and related to your voltage problem. Sometimes a battery will show 12+ volts but upon loading, drops off. Did you load test your battery? Your voltage while the engine is running should be around 14V, if your charging system is working. Your low voltage could be keeping your fuel shutoff from pulling all the way over.

Is there any smoke when it bogs down? Really black smoke could be a clogged air filter.

Could also be a loose drive belt.

Good Luck

 

[ProudMarineDad]

Downey, the problem started before the filter change. Had blown ignition fuse, repaired then changed the filter. shane there is no black smoke when it bogs down. i will load test the battery today. Then i will go from there. I have never worked on these machines(shadetree mechanic) but i learn something everyday. I think i will be talking to you guys again in the future. thanks again for all the help and directions.

 

[Steve Frazier]

I doubt the two problems are related. I'll address the power problem, you're definately having a fuel delivery problem. In addition to what shane suggests with the fuel pickup at the tank, make sure the fuel lines themselves are clear as well. On my old JD410, gunk accumulated at one of the 90 degree bends in the steel fuel line so that it wouldn't run in cold weather. It drove me nuts until I drained the tank, flushed it and the lines and discovered the gunk.

 

[bobcatmechanic]

do not blow back through the fuel lines it will blow of your pick up tube on a bobcat also the pick up tube should be either in front of the hydostat right below it or behind it start there and check it to make sure its clean and the rubber line is not cracked that does in the tank also they are notorious for pinching fuel lines make sure all the lines move free and are not under the motor mounts also while you have the pick up tube out there is a metal 90 degree fitting check to see if its clear fuel pressure i think should be around 6 psi or so after the fuel pump

 

[tyler111]

I have this problem on my 864, I sank it in mud and watter, run it for about 20 minutes in water, pulled it out, huge amount of watter in oil, three oil changes later and now it runs perfect, but when you put it under load like 3/4 to full throttle and start to drive it blows huge amount of black smoke and wants to die out. I found this part missing, but dont know what it is or if it is an issue at all.

 

[willie59]

I have this problem on my 864, I sank it in mud and watter, run it for about 20 minutes in water, pulled it out, huge amount of watter in oil, three oil changes later and now it runs perfect, but when you put it under load like 3/4 to full throttle and start to drive it blows huge amount of black smoke and wants to die out. I found this part missing, but dont know what it is or if it is an issue at all.

Welcome to the forum tyler111. :usa

Is that a Deutz/Bobcat engine?

 

[tyler111]

Yes it is a Deutz . I would like to post a thread about it but for some reason am unable to do so.

 

[tyler111]

Also it starts fine, idles fine and when it is sitting you can throttle full and runs perfect, but the minute you take off under load it looses power wants to die and huge black smoke continues the whole time. Sitting full throttle no black smoke very little blow by.

 

[tyler111]

Also I did change the fuel filter and air filter, air filter is now perfect...

 

[willie59]

tyler111, your now a junior member. you can now start a thread.