455 won't start...but it cranks

iowa · Mar 22, 2019

I have this problem more and more frequently. I'd say that about 3 out of 5 times that I try to start the 455 it just cranks and cranks but doesn't start. Sometimes it does this after it has been running for a while and I turn if off then try to restart and other times it won't start when it's been sitting.

I bought a Brake Safety Switch (AM12895) but I'm not sure that is the issue. I can't figure out how to take the old one off. It looks like it is riveted to the frame.

Any other suggestions for me?

Yesterday, it hadn't been started in 2 weeks and it wouldn't start after trying it several times over a 1/2 hour period. Then before I walked into the house for the day I tried it one last time and it started as quickly as I turned the key.

thanks

IH3444 · Mar 22, 2019

Does it have an electrical fuel shut off on the injection pump? Check wiring, and fuse for corrosion, or not tight fits.

Kish318420 · Mar 22, 2019

Bunch of thing's to check, safety switches for engine to actually start (ignition), fuel shutoff solenoid, fuel pump losing prime, injectors/injection pump issues, key/ignition safety interlock board.

jaxs · Mar 23, 2019

I agree it's most likely fuel shutoff malfunction,second most likly low pressure (lift) pump issue and third possibility of clogged strainer or filter. My guess is that + is applied to shutoff when key is on and - is applied to shutoff after passing through all safty switches. Either could intermittently fail but - is the most likely. Unless you have a wiring diagram or other means of knowing which is - and which is + terminals on shutoff,next time the engine is running,test with volt meter. Next time it fail's to start,jumper to the shutoff then try starting. If that doesn't work,disconnect fuel line at shutoff,filter or elsewhere between fuel pump and injector pump,turn key on to see if it's pumping fuel. If not,you'll need to see if pump is bad,pump has faulty connection or if something is clogging fuel path. It's a process of elimination.

Richard001 · Mar 24, 2019

jaxs said:
I agree it's most likely fuel shutoff malfunction,second most likly low pressure (lift) pump issue and third possibility of clogged strainer or filter. My guess is that + is applied to shutoff when key is on and - is applied to shutoff after passing through all safty switches. Either could intermittently fail but - is the most likely. Unless you have a wiring diagram or other means of knowing which is - and which is + terminals on shutoff,next time the engine is running,test with volt meter. Next time it fail's to start,jumper to the shutoff then try starting. If that doesn't work,disconnect fuel line at shutoff,filter or elsewhere between fuel pump and injector pump,turn key on to see if it's pumping fuel. If not,you'll need to see if pump is bad,pump has faulty connection or if something is clogging fuel path. It's a process of elimination.

You will want to be careful about jumping battery voltage to the shutoff valve. These valves have two circuits, the pull-in and the hold.

Applying battery voltage to the pull-in for more than a second will burn out the coil. The hold circuit in meant to be on continuously when the engine is running. The procedure is to apply the hold coil with voltage then momentary apply voltage to the pull-in coil.

Richard

iowa · Mar 25, 2019

K7LN said:
The first thing I would do is turn the key on to the RUN position without trying to start it.
Then listen by the seat if you can hear the electric pump in the tank running.

Am I listening for a constant buzz/hum from the electric pump?

If so, I hear it when the 455 doesn't start and, of course, when it does start.

iowa · Mar 25, 2019

K7LN said:
There are two electrical systems on the 455. You should post a serial number to identify if you have the early or late model.

Next test - with the key turned to RUN but not starting it, do you hear a somewhat loud click from the engine area? This would be from the fuel shutoff solenoid activating. You should also be able to see it move.

Sadly

it's starting every time I've tried today. I'll keep starting it and make note of whether I hear that click when it doesn't start.

I'll check into the serial number and get back.

thanks

iowa · Mar 27, 2019

Hey, I think we're on to something. Today it wouldn't start and I DIDN'T hear the click in the engine area when I turned the key and it didn't start. I did hear the hum of the pump under the seat though.

I also noticed that the solenoid sometimes doesn't fully 'pop' out after it plunges when I start it. Does something need lubricated or should I just replace the solenoid?

thanks

Diggin It · Mar 27, 2019

Grounds. Check your grounds. Fuses and all else can be good, but if a ground point is corroded or loose, things can be intermittent.

Also, wires can be degraded inside electrical connectors. Everything can look good to the eye, but the wire may not be passing power to the connector or vice versa.