1999 kenworth W900l has a 3406E Cat 475 hp was idleing and died. Now will not start. Has code 46. We have power to ecm and have replaced several sensors. It will run on ether but that's it. Changed fuel filter and some fuel lines. Still will not start. Any suggestions will be appreciated.
IIRC a code 46 has to do with low oil pressure but I'm not 100% for sure. Hopefully someone will chime in and confirm this or correct me if I'm wrong.
You are correct it is low oil pressure fault. Best get a manual gauge on it and see what that says
Are you sure the fuel system is primed. Hand pump will get hard to pump and you should hear fuel draining into tank from return line. Operate the primer pump while cranking engine. Does the oil gauge register anything while cranking? My best guess is the cam rotation sensor located front left on the front structure failed. I have had these fail at idle and road speed. If you haven't changed that sensor already. Have you checked the lift pump PSI at main filter base it should read 40 psi just cranking, 75 psi running. Truck Shop
It will probably be either lack of fuel or lack of electrics. As truck shop noted, the hand primer should be hard to push. If these engines do get airlocked they take a lot of cranking to bleed. If you lose a speed/timing sensor it will need longer to crank but it should still start. The other possibility is you have lost a power to the ECM. There are three or maybe four positive feeds and a couple of grounds. If you lose any of them, it can lead to a no start. If you post your serial number, we can let you know which pins are +ve and -ve.
2ws01267
Thanks for your replies. We have replaced the cam sensor, crank sensor, and the oil pressure sensor. We had a hand pump on the motor, but we took it off. When we got the truck it didn't have the hand pump so we thought maybe adding it was a problem. We can put that back on the motor if you think it will help. We also replaced the regulator valve by the fuel filter. We have used the hand pump several times and pumped and pumped it, but it didn't seem to help. We don't really know what else to try. Thanks again for your help.
On the ECM there are two plugs. One goes to the engine sensors and injectors, the other one joins the chassis wiring. On the chassis plug you should have; Permanent battery positive to pins 48, 52, 53. Permanent battery ground to pins 63, 65, 67. Ignition switched battery positive to pin 70.
I forgot to mention we have changed the transfer pump too. Thanks.
Ok. We will check that in the morning. It has gotten too late tonight. Thanks again.
7.3 Power Stroke used the Cat type system.\ If engine lube press. is low it will not feed the high press. pump that actuates the injectors. I understand that feature saved a few Power Strokes from destruction.
The 3406E injector relies on a cam lobe for the injection pressure (MEUI). You are referring to the HEUI system which doesn't apply in this case. Good thought though.
Hi, Thanks again for your help. We have positive battery on pins 52 and 53. We didn't know to check pin 48. We will check that this morning.
There is a breaker in the power distribution box also. It operates off the switched ignition for the ecm. Truck Shop
Hi, We checked pin 48 and there is nothing at this pin. no wire. It came from the factory that way.
Hi, Does anyone have any suggestions, ideas, comments, etc.? Thanks.
Is the hand primer very hard to push in, like you have to lean your bodyweight against it hard?
It's not real hard to push in, not like bodyweight hard.
What do yall think about not having anything at pin 48?
If there was nothing on pin 48 from the factory and all the other pins check out ok, don't sweat it. If the hand primer isn't hard to push, it sounds like you're not building pressure in the primary fuel system. Look at your filter head. To the right of the filter going vertically up from underneath should be a hex. That's the pressure regulating valve for the primary fuel system. Take it out and check it for debris.
Hi, we put a new pressure regulator on, but we will take it off and check for debris. Thanks
I would say you need someone to connect ET and check out if you're getting any errors and a good speed/timing signal. Are you getting any smoke? Can you hear the injectors firing?
Is the primer pump brand new or used? When it starts to build enough pressure using the hand primer it will normally give off at buzzing sound from the primer pump. Remove the fuel return line from the tank and check for return fuel when priming. A good primer pump will dead head 40 psi. The reason I ask about the condition of the primer pump is the fact that there is a check valve built into the primer pump. If that valve rolls over or is screwed up it will stop the fuel flow and will not prime the fuel system. And the fuel system on a cat should always have a hand primer pump. Truck Shop
And.. Just a "heads up", in the last 5 years I've had 4 new cat primers that were junk out of the box. New does not always mean "good".
Good point on checking the hand primer. There was a period where the rubber piston inside would break up and block the fuel flow. Although that was about 15 years ago mind you, and I thought they had them all out of the system by now. But you never know.
TBH, the current crop of Cat's short stroke primers are junk. The long stroke primers on the D-9L, etc are fine. but the short stroke primers on truck engines seem to work fine in the shop changing fuel filters, but when it runs out of fuel on the side of the road... better have a spare with you. Rant over.
Boy! howdy on that one, been there. Had a primer last fall take a dump as the truck was pulling out of the shop. We keep only long stroke primers on hand. With the short stroke primer they always seem to leak past and you end up with more fuel on you than in the filter. Truck Shop
In your fuse panel the bottom left is a fuse "eng pwr" this is your power for pin 70 on the ecm. the bottom row of fuses seem to corrode, make sure its good. When you key on the warning lights do a few second check then go off, the yellow check engine light should stay on a bit longer, this will show the ecm is powering up ok. To check fuel, remove the fuel line at the filter head that comes from the back of the engine head, pump the hand primer pump till fuel comes through, pump out a quart or more then reconnect and pump till good pressure is felt. should fire up at this point. just my two bits worth, hope it helps.
Did you ever get the truck running?
No Start Cat While you are cranking this engine over does the tachometer register and if so what RPM are you able to achieve.
Hooray!! We finally got the truck to start and it is running great. We think it was "air locked". Thank you everyone. Your help was invaluable. Probably would not be running yet without your help.