had hydraulic pump guy out today all pressures are good. pump is in spec.he said it is a fuel delivery problem. possibly plungers but the pump has been remanned less than 50hrs ago. can plungers go bad that quick? how much fuel should be flowing when you pull off the return line?
Don't do anything to the injection pump just yet, it is the transfer pump or the feed lines to that that are the issue.
if the fuel is getting the main pump enough to run does that not mean the transfer pump is working?
There are many variables, This has been a difficult job to help with. I suspect as do others there is a fuel supply problem. If we where at your machine there is much we would see and help find the problem. Just need to perservier and get to the bottom of it. Later Bob
when the machine is on 10 or hi. if i pull off the return fuel line i take about 4min to fill a ltr jar . Is that too slow? I am going to make sure the banjo bolt screen is clean tomorrow.
And fuel supply problems can be elusive. I've found twigs lodged in the shut off valve at tank, even had a Cat 320BL that shut off valve was malfunctioned, you'd turn the knob open unit it stopped, figured valve was open, turned out, defective valve was only opening about a 1/4 open, restricting fuel delivery. And don't forget the tiny strainers inside banjo connection fittings. I don't know if your machine has one, but those have a propensity to get clogged.
Best solution is to get a pressure gauge in the pump and check fuel pressure when the engine is under load. Should have about 30 psi at high idle and 20 psi under load. If pressure drops below 20 psi the supply is clogged or not getting there. Later Bob
A 330B running at full power consumes about 40L/hour, 4minutes to fill a literjug translates to a flow of 15L/hour and is nowhere near what it would need.
If you are 100% sure there's no problems in the lines or filters go ahead and remove the transfer pump and check the spring and checkvalves, usually you can see on them if the are bad.
the transfer pump is brand new. also i was talking about the return line not feed.
have you checked the wiring to your proportional reducing valve? We have a 330BL and had a partly broken wire close to the plug in the wire looml. It would also stall under a load. Not throwing you away from fuel prob. just something we have run into in the past.
Ok, then, it's time to put a gauge on it and measure the fuel pressure, there's a port on the fuel filter base with a plug, should be atleast 100kPa all times.
I went back to original post, no smoke = no fuel, . Blow out fuel lines, double check filters. Check fuel pressure. Try running transfer pump when engine dies, Is left track still slow?
If fuel pressure checks out, double check fuel pump timing, 3306 known to retard when torquing gear to pump, will usually smoke a little blue though. Late timing.
This is going to be a stretch, and I am no mechanic, but I have had 2 3406 engines that would not run under a load. There are 2 check valves in the primer pump, each about the diameter of a dime. Somehow one of those check valves can get flipped over. It is a very simple primer pump - fuel comes in through one of the check valves when the plunger is pulled out, then leaves through the other one when the plunger is pushed in. At least on the 3406's, the fuel runs through the primer pump when the engine is running. The 3306 in the 330 may be much the same. It only takes a minute to remove the primer pump and inspect those little check valves (2 small bolts), and if they look indentical one of them has flipped over, as the outlet side and the inlet side of the check valves look different. Again, you may all be laughing at me for posting this, but it is very easy and quick to check this (as even I can do it) and it just might save $1000's of diagnostics. I'll keep my fingers crossed that this is the problem softmachine! Good Luck!!!
Oxbow, I for one want to thank you for posting this because this is just the kind of thing we have to learn from eachother and not the manuals.
My pleasure shopguy. I first learned about this when a friend of mine had problems with his new truck. He had just switched from Cummins Big Cam 400 to a 425 3406B, and was notat all pleased. He took it to the Cat Dealer and the shop forman, after listening to the problem, said let me go check something real quick. He went out and in 5 minutes the truck was running great. I though to myself, self-you better remember what you saw here today cuz it may save you some grief someday. Sure enough, about 4 years later, traveling through Southern Utah, my truck quit running but it would idle just fine. After changing fuel filters (always the first thing that comes to my mind) with no success, I finally remembered what had happened to my friends truck. I popped the primer pump off and studied those two little check valves. It took me a while to figure out which one had flipped, but that is all it was. It happened one more time years later on a 980C. Again, it's a shot in the dark, but it doesn't cost anything (except for maybe the gasket) and a few minutes to check.