Project 8 3CX stopping and starting.

[jd6820]

Sorry Guys, you are being so helpful so I would like to ask another question if I may please. While I was working on the injection pump solenoid I noticed something else that could be on the same cable. The parts site tells me it is a "Switch temperature" and it is screwed into the front of the cylinder head. But then, in the thermostat housing, there is what looks like a normal temperature sender only this time it is labelled as "Sender temperature" which I presume sends the signal to the temperature guage in the dash. Can the "Switch temperature" in the cylinder head also trigger the injector pump solenoid so that if the engine gets too hot it will shut it down ?

No it's the pump advance that's triggered by the current supplied by the temperature switch.

 

[Gecko]

However, if that wiring harness has a loose tubular sheath on it then you need to be sure it can’t get moisture in it from the other end?

It's just a tube for protection. It was never meant to be sealed.

 

[Scraperman]

Some self amalgamating tape might be a better choice to seal it up, won’t be as pretty as the proper boot, but probably just as watertight. However, if that wiring harness has a loose tubular sheath on it then you need to be sure it can’t get moisture in it from the other end? In that case it’s probably best left as it is?

I'll have another look where the other end of the cables go. One place is the injection pump solenoid. I noticed that somehow they all seem to be connected to a small terminal on the end of the starter motor. Maybe that's where the electrical current comes from ?

 

[Scraperman]

No it's the pump advance that's triggered by the current supplied by the temperature switch.

Thank you. Not sure I understand that but thank you anyway.

 

[Scraperman]

It's just a tube for protection. It was never meant to be sealed.

Mmmm. O.K. Thank you. I won't mess with it then.

 

[jd6820]

Thank you. Not sure I understand that but thank you anyway.

When starting from cold the engine usually needs to alter the timing to aid cold starting. On the bottom of the fuel injection pump is a valve responsible for for advancing the injection timing event. This is controlled by the temperature switch you have identified on the cylinder head. Often fed with power by the same supply feeding the stop (fuel shutoff) solenoid. When the engine is cold this feature is active till the engine temp rises enough to break the circuit. There is usually another temp sender that sorts out the temperature guage/warning light, I think located in the thermostat housing on most perkins lumps.

 

[Scraperman]

When starting from cold the engine usually needs to alter the timing to aid cold starting. On the bottom of the fuel injection pump is a valve responsible for for advancing the injection timing event. This is controlled by the temperature switch you have identified on the cylinder head. Often fed with power by the same supply feeding the stop (fuel shutoff) solenoid. When the engine is cold this feature is active till the engine temp rises enough to break the circuit. There is usually another temp sender that sorts out the temperature guage/warning light, I think located in the thermostat housing on most perkins lumps.

Thank you. That was very informative and makes total sense. I have a tractor that I have to unscrew the valve that is positioned under the injection pump to aid cold starting. But this particular tractor came down the line in 1965 and so things have obviously progressed.

 

[V8Druid]

the old Simms inline pumps used to have an 'overfuel'/cold start button in the centre of the stop lever pivot ... press it in on a cold morning

 

[Scraperman]

the old Simms inline pumps used to have an 'overfuel'/cold start button in the centre of the stop lever pivot ... press it in on a cold morning

Yes, the old Fordson Super Majors had that system and they would bark into life. But they were direct injection which I felt always helped.

 

[Scraperman]

Sorry Guys but could I knock this topic back into life please ? I am still getting times when my digger just won't fire up. But usually, if I fiddle around with the rubber shroud on top of the fuel pump solenoid, she will go. As I wrote earlier in the topic, I have renewed all the connections in that area and replaced the relevant fuses and so I am thinking that it must be the fuel pump stop/start solenoid. Could anyone tell me how easy these are to replace please ? Do they just unscrew and pull out after the connectors have been removed or is it a more difficult job than that ?
Thanks in advance for any help and/or advice anyone can give me.

 

[DaveDCB]

Your explanation is correct

 

[Scraperman]

Your explanation is correct

Thank you @DaveDCB. Does anything have to be aligned when putting the new solenoid in position ?

 

[DaveDCB]

Just unscrew and screw back in, should look like this.. pretty simple as far as solenoids go.

 

[Scraperman]

Just unscrew and screw back in, should look like this.. pretty simple as far as solenoids go. View attachment 49933

Now that is really very helpful of you @DaveDCB . Thank you very much indeed. Would you know if that is the correct solenoid for the injector pump on my machine ? I have found the part on the JCB web site (No. 2 on the diagram below) but it looks as if there is a spring, sealing washer, and a couple of other things included in the part.

 

[DaveDCB]

That I wouldn’t know, I just searched for Perkins 1000 engine stop solenoid, but depending on the exact age of the machine I believe they had different engines in.. infact the Perkins 1000 engines may have only been in the P12 machines….

 

[craig]

The other bits are as you say the sealing washer, and a spring, the other bit is a metal plunger with a conical rubber seal on the end. The spring pushes the plunger onto its seat, to stop the fuel flow, with the ignition on the coil energises and the magnetic field pulls the plunger off its seal to allow fuel through.
Some kits come with all the parts, some are just the coil.

 

[Mick-the-fitter]

Serial number of machine, I will check on engine/pump what age is she?

 

[Scraperman]

The other bits are as you say the sealing washer, and a spring, the other bit is a metal plunger with a conical rubber seal on the end. The spring pushes the plunger onto its seat, to stop the fuel flow, with the ignition on the coil energises and the magnetic field pulls the plunger off its seal to allow fuel through.
Some kits come with all the parts, some are just the coil.

Thank you for that @craig . In the diagram it looks like 2 individual pieces of very small identical tubes that are shown under the spring but maybe it is all one piece ? And another question if I may : When the solenoid is unscrewed and removed presumably care must be taken not to lose the spring, washer, plunger etc. if it isn't included in the kit that I buy ? Do all the bits just sit in the recess of the pump or are they attached in some way to the actual solenoid itself ?

 

[Scraperman]

Serial number of machine, I will check on engine/pump what age is she?

That would be helpful @Mick-the-fitter. I have been getting confusing information from 2 suppliers today ! The machine VIN No is 412168. The date of 1st registration was 01/11/2003. I always thought that it was a Project 8 but I may be wrong about that. This is the best image I have of her. Hope it helps and thank you again for your help.

 

[Mick-the-fitter]

3CX Sitemaster Turbo, engine type Perky 1008, that should be the right solenoid valve