New holland l785 no go no star no fun

[Rayhat]

1992 diesel. Fourth owner 4K hrs. Go to purchase running fine. Lifts turns backwards towards everything it should. Pay for it 5K. Load it up get it home pull of trailer. Leave it idle for 10 minutes to park trailer lift bucket up half way and she stops all hydraulics. No control at the sticks no controls at the pedals. No up no down no back and forth. Engine sounds fine. Shut it off to see if boom will leak down, nothing. Go to start it total zero. No crank no starter noise no nothing. Turn key to start, Hyd Charge light, alt light, engine oil press light come on and constant buzzer. Engine oil low, hydraulic oil low and milky white. Remove drain plug from reservoir (nice mess) drain everything I can, hydraulic hoses where I can. Remove suction screen completely clogged. Soak in kerosene clean up nicely soak and clean breathers. New filters, 22 gallons new hydraulic fluid, new oil and diesel filters. Fill hydraulic filters before installing. Buy new bigger wrenches. Get operator and service manuals. Get in go to start same thing. Three lights no turn over steady buzzer. Do I need to prime something, is there a sensor stuck giving a false reading. Why can't I find anything about that buzzer. Does the seat switch have some control over the starting ability. I'm leaning towards electrical, but why did I loose all hydraulics. Got plenty of milky white fluid at screen filter in standpipe when I removed cap. Not sure how much fluid I got out, definatly 10-15 gallons. It doesn't look abused shows some neglect. Low fluids.

 

[Mikefromcny]

Not sure I am following you here. Dash lights are on but starter won't crank, and it lost hydraulics?

 

[Rayhat]

Yes. I contacted last owner and he says theres a loose connector in the cab and this has happened to him before. Going to check after thanksgiving

 

[Rayhat]

Yes. I contacted last owner and he says theres a loose connector in the cab and this has happened to him before. Going to check after thanksgiving

 

[Mikefromcny]

What year is the machine? I used to own a '83 L455 NH skid. I don't remember there being anything that 'enabled' the hydraulics.

 

[tmc_31]

Check the seat (safety) switch located on the bottom of the seat. Yes, if this switch isn't made, the loader won't start and it also locks out the boom hydraulics. I had similar problems with a LX565 that I owned. Sometimes I could bounce up and down on the seat and get it to make.

I also had a lot of trouble with the seat belt safety switch. It is in the same circuit as the seat safety switch.


Tim

 

[shorton]

Sounds like the seat switch to me. Make sure when putting the seat back in that the wire harness for the seat switch doesn't get caught under the seat; that can cut the wire. There is a switch on the bottom of the black box on the right hand side when you are sitting in the L785. You can flip that switch to put it in test mode; this will bypass the safety switch. I wouldn't leave it there though.

 

[Rayhat]

So I spoke to previous owner and he says the main electrical connection at the bottom of the control module in the cab comes loose and kills everything. It has happened to him before more then once. ok. Loose connection at ignition module is the big problem. So now we know. Little dielectric grease and some support to get past that. Now lights go out when cranking as they should, but I lost the diesel prime. She cranks fine but no fuel to cylinder. Trying to find info on bleeding air out of 3.3l Ford. Looks like I have to remove engine shroud to get to injectors at the block. Can't find any bleeders at the fuel filter or pump. Tried hand priming with the key on and while cranking no luck. She cranks and a slight puff of exhaust comes out. And I mean like a lite drag on a cigarette. Just put in 5 gallons of diesel so she has fuel. That's the update. My first diesel. Learning as I go. I jumped it so as to give it enough turnover. No fuel at injectors I believe.

 

[shorton]

Sounds familiar, brings back painful memories. I'm not an expert, but here is what comes to mind: Key needs to be on as you stated above for the fuel relay to be open to allow fuel into the injector pump. The hand pump has 2 rubber diaphrams inside to create suction and prevent pressure from going backward. My hand pump was bad and both diaphrams needed to be replaced (I purchased from Messicks, not too expensive and they have the parts diagrams online). Getting the air out of the pump is painful. There is an air bleed screw (looks like a zerk or nipple) on the left side of the main body of the Lucas/CAV pump, put a 5/16" or so wrench on that a loosen it a little--then pump the hand pump until fuel squirts out of the nipple/zerk. If no fuel comes out, then a) could have an air leak between the tank and the pump (possible pickup tube in the tank, leaking at the fuel filter, or some other line loose...), b) even though you have the key on, the fuel relay at the bottom left of the Lucas/CAV pump is not kicking out to allow fuel passage (to test this, pull the wire off and try turning it over while watching for spark, or put a test light on it), or c) the Lucas/CAV pump is frozen inside due to corrosion or junk that got in there. In my case, the Lucas pump was frozen and I needed a rebuild. For me, this happened when I allowed the fuel to get too low and lost prime--loosing prime was just the little thing that pushed my pump over the edge. If you do get fuel squirting out of the air bleed / prime nipple/zerk thing, then, that's when you need to loosen the 4 fuel lines that go to the injectors on the top of the motor. Once fuel starts to come out of those pretty good or its trying to start, snug those tight again (don't strip them) and it should fire up. It will still have a little bit of air in it, so if its got a lot of engine wear, you might need the help of the engine compression to get it to suck fuel through it, so you might need to use a little spray ether into the intake--small burst squirts to get it going while someone else it sitting in it cranking. Good luck, that's the worst crappy part of owning one of these.

 

[Rayhat]

Ok so long time away. That's because she's a runnin b-tch. The jerk that changed the fuel filter(me) didn't fill it with fuel before installing it. Filled it up and she ran great. Movin skids clearing brush junkin scrap everything I wanted to do with it. Now new problem. Cracked front axle tube. When I finished the last time I used it I saw a small puddle in the rim. Had seen it once before and thought seal leak. Said ok used it again saw more fluid and checked reservoir. Low. Real low. Saw big wet spot pulled rim and saw healthy crack. Cleaned axel better and found old welds and lots of grinding and cracks around tube where it meats the body. So I have some welding to be done. Looking for the quick attatch to swap on I still have the pin on system. What a pain. Half an hour swapping one attatchment for the other. The pin on points do not look factory on the Attatchments and the pins ore loose one to long, but they work. It's still a good deal though. I'm Still happy I own it.