Jerry/MT
Elite Member
- Joined
- Feb 2, 2008
- Messages
- 3,140
- Location
- North Idaho-The Palouse
- Tractor
- New Holland TD95D, Ford 4610 & Kubota M4500
The fact that it idles throughout the rpm range but won't run under load implies a fuel delivery issue. Most commonly this is cause by a blockage at the tank strainer, the fuel filter head, or the fuel filter itself. You changed out the fuel filter so that isn't the problem. Remove the fuel cap, open the line at the tank out let and use compressed air to blow back through the tank strainer. If you get a temporary reprieve from the symptoms then you've found the problem. Bacterial sludge can form in the tank due to water in the fuel. Water can get in there from normal condensation and you'll need a biocide to kill the bacteria. Sea Foam won't do it. If there is a clog, you have to drain and flush the crud out of the tank or it will be a recurring problem. Keeping the tank as full as possible can help reduce water accumulation. If treatment with compressed air does not work, check the fuel passage in the filter head to make sure it is not clogged.Nothing like surgery to take you off-line at the tractor and the internet
(Original question was about engine surging on a Branson 3510H (year=2010). Engine rebuilt and injector pump replaced 200 hours ago (under warranty)
I changed the fuel filter - it didn't have a lot of crud. Also changed air filter, since it was quite dirty.
After changing the fuel filter I primed the system - or thought I did. I opened each nut (flared pipe), one at a time.I cranked it until bubbles stopped, and tightened the nut. The difference in how the engine ran was insignificant.
Ignoring Einstein's advice, I tried the same thing again hoping for a different outcome.
The next time I opened each nut more - one at a time - and cranked. I got a feeble spray squirting out if each fuel line. I was expecting a flow of diesel.
QUESTION: is this the right way to bleed it?
When I started the engine, it started easily (all things considered). It runs without surging. Too soon to celebrate! Moving throttle handle 1/2" either "faster" or "slower" made the speed move instantly to 500 or 2100. Not slowly, instantly: before I could count "one thousand-one" either way (faster or slower), the speed flips between minimum and maximum.
Sorry Einstein, but I did it again. Now it runs mostly smoothly (very slow and small fluctuations) but has very little power.
By the way, I'm sure the dealer drained the fuel: the fuel gauge has been wrong all the time, ever since.
Since bleeding makes a difference - but not enough difference, I assume that there is some blockage or remaining air bubbles.
- I idled it several minutes and then ran it at 2100 for several minutes. It runs runs smoothly, but it has "no" power. At 2100 lifting the bucket slowly almost kills the engine.
- I backed the tractor up a small incline and ... it kills the engine.
What should i try next?
Generally bleeding the system consists of bleeding at the filter head , bleeding the pump, and then bleeding the injector lines ( not the injectors themselves). You owners manual should tell you how to do this for your specific model.. If you don't have access to one, I can give you some general instructions.