Hello all. Been sometime since my last post. This time my 426 will not start. History is the injector pump went out couple of years ago and replaced it and all kinds of fuel problems that i finally straightened out. This is the Cat 426 model and sn is 7BC00580. I managed to clear up all the problems and the machine has been doing good until yesterday when i was spreading gravel on my driveway, which is now blocked with 2 piles of material plus the 14 000 pound machine. It actuall died all of a sudden and would not start. It is getting fuel to the pump as i have an electric pump low volumn on it. I cracked the injector lines and nothing come out. The return line has only a drop or two coming out. The electric solenoid is disabled so i have to shut the engine off using the manual toggle each time. SO when trying to start the engine it acts just like it does when i forget to return the manual toggle to the run position. So question is, did something go wrong under that top cover of that pump? Could the arm for that toggle be stuck? I have never torn one down so don't know what there. Maybe somebody has had this problem before?
What kinda pump is it.. Get mdl off tag on side of pump.
It is a Lucas Cav 54W 3343F742
There is a filter in the inlet side of the pump..under the big nut 15/16.. Remove the nut, the copper gasket, and the large spring.. Be careful when you remove the spring, parts WILL stick to the bottom of it.. Next, hold down the rest of the guts in the end plate with a screwdriver.. & with a 90* pick/scribe fish the plastic filter out from the side of the hole.. BE SURE TO HOLD DOWN THE GUTS.. Blow off the filter and reinstall. Let me know if it was dirty or not.
Ok! sounds good to me. I never thought of that. Yes it does get fuel to the pump but nothing seems to be coming out. So that just may be the problem. Thanks so much.
BTW, what happens if i do accidently let the guts out? Can i put them back or?
Ok did all that and the filter was clean. The spring and that little plunger thing was dirty and i cleaned it best i could but looks like they had rust on them. Results: still wont start and still no fuel from return line. Tested it at tank and the pump. Has good flow to inlet of the pump too.
Did u change the main engine fuel filter.??
been working on it and still no start. And yes all filters are clean and when i loosen the inlet line by that big nut, there is a good stream of fuel out. squirts out.
is it possible that the manual shutoff linkage inside that top cap has broken? came loose? cause when trying start it the engine sputters and trys to start just like it does when i forget to return that toggle back to run mode?
Have u bled the air at the bleeder by the name plate.?? Have u loosened ALL the lines AT THE INJECTORS.?? Is the nut tight on the shut off lever AND throttle..?? Don’t snap it off..
yes,there are 2 bleeder screws on the pump. The lower one runs freely and has plenty of volume. The top one has no fuel coming out of it, maybe a drop or two. There must a passageway that is plugged within the pump.
One last test.. Remove the inlet fitting if it’s a 90*.. Fill the inlet hole with fuel to the top.. Crank the engine over a couple revolutions.. now go look at the fuel in the inlet hole.. Is it still there or did it get sucked down..?? If it’s still there,‘u have problems..
I already know it will not suck that fuel in. So what kind of problems is there?
The insides aren’t turning.. (Seized)
doesn't sound very good. does that mean the shaft is twisted in two , its not rebuildable?
To b absolutely sure, u can take the 4-5/16 screws out of the “end plate”, remove it and bump the engine to see if the center turns.. All it takes is a “bump” to tell.
Ok will try that tomorrow as it is dark here now. Is that plate on the back of the pump? and are there any parts that will fall out i need to look for?
also, what is next step if it turns? or if it does not turn.
Either way u have to pull it off.. If u just BUMP THE STARTER, nothing will jump out atcha. U just wanna see if the pump will turn..
thats what i thought and no sense in me trying anything else, just pull it and get it over with, LOL I was hoping i could get it started and get it back to my shop area. It is stuck right in the middle of my 1000 foot driveway and no way to get around it. Using my neighbors drive to get in and out.
Have u checked the shut off solenoid.?? Remove the solenoid (15/16) and see if u can get the plunger and spring out and screw it back in and rebleed it.
solenoid does not work. The plunger has been removed as it was shutting the engine off everytime i dropped the bucket. That is why i been using the manual shutoff. Has worked this way for three years. I did buy a new solenoid but it did the same thing and thats why i modified it. I want to thanks you for your help. I understand you rebuild pumps and problem i have is an immediate remedy to get that loader out of the driveway. I cant wait a week or two to do that so gonna have to find someone locally to do that.
I understand.. but unless u find someone that’s sympathetic to your problem, it’s still gonna take that long.. You’ll be days ahead if u just buy one off the web.. If the head and rotor is in fact seized, you’ll only get half of the core charge back.. If u get it done locally, they’re gonna hit u with LIST PRICE for the H&R.. Good luck.
Ok thanks for your help. I am between a rock and a hard spot, so they say. Have a good evening.
well, the rain let up and allowed me to pull the pump. I discovered, i think , what the problem is. As i said before the electric solenoid would shut the fuel off when i dropped the bucket too hard. So i i took the plunger out and used the manual shutoff to kill engine each time. After pulling that pump i noticed there is a valve that moves in and out?? as the solenoid was used, well that fixed valve appears to be frozen in place. It will not move when i press it with a screwdriver. Is that normal?
Where is this valve.. R u talking about under the top cover.?? How about a picture..
NO its the one that is internal where the solenoid screws in and operated by the solenoid. When rain stops i will get pic.
The only way to disable the solenoid is to REMOVE the plunger and spring.. How did u disable the solenoid..
removed the plunger and spring.
Ok i got it figured out. That part is stationary.
???
Ok back on this thing again. Took pump to a local shop and was torn down and inspected and then bench tested and all is/was well. Reinstalled pump, all new filters and drained diesel tank and replaced all diesel and installed extra inline filter. Bleed all lines and fuel filters and injectors and still won't start. Have tried everything possible and still wont fire up. Pump bled , top and bottom until no more bubbles. Engine turns over and has some black smoke out the stack but just wont start. There is fuel coming out when bleeding injectors. So, bottom line is, does not appear that i had fuel problems in the first place. It must be something mechanical that i am overlooking and MAYBE somebody out there knows what the problem is. At least i am hoping. HELP Please!!