Perkins 4108 Stalled and won’t start

[SailnParadise]

I am not getting fuel out of the return line. And when I crack the nut on top of the injectors I'm not getting any fuel leaking. I've routed my fuel lines to a 5 gallon jerry can in the bilge for now. I've also correctly installed an electric fuel pump. I was noticing the primer bulb I have in line stayed hard once full. Fuel comes out fine from the injector pump.

[GrowleyMonster]

Originally Posted by SailnParadise

I am not getting fuel out of the return line. And when I crack the nut on top of the injectors I'm not getting any fuel leaking. I've routed my fuel lines to a 5 gallon jerry can in the bilge for now. I've also correctly installed an electric fuel pump. I was noticing the primer bulb I have in line stayed hard once full. Fuel comes out fine from the injector pump.

Elevate the jug higher than the engine. This ensures that the system fills with fuel and not air. Meanwhile look for any fuel seepage from connections. That will be where air is getting into the system in normal operation.

You might want to change the engine mounted fuel filter. Be absolutely certain the gasket is libricated with a little clean grease and the filter fills up with fuel and there are no leaks.

https://tadiesels.com/assets/docs/te...20Changing.pdf
That is a good reference for you. Notice on page 5 the illustrations of the two common fuel pumps used. Be sure you are bleeding at the correct screw. Should take a 5/16" wrench.

When you bleed the injector pump, if it is operating correctly, if there is all fuel and no air coming out the bleed port, then fuel should be coming through the return line and through the injector lines. Verify, re-verify, triple verify before you start spending money on a mechanic. Finally check the anti-stall device as per the above document, and make sure that the fuel shutoff is not shut off and the throttle arm can move freely when the control cable is disconnected. This might be hard to get at.

I haven't messed with injector pumps and most owners will have a mechanic check, repair, rebuild, replace, or re-install the injector pump. It can be done wrong a lot more ways than done correctly.

[SailnParadise]

I changed the fuel return hose and checked the secondary filter. I am bypassing the tank and Racor via 5g Jerry Can. I am getting solid fuel from the injector pump. And fuel squirting then I crank with injector cracked. But I am getting no fuel from the return fuel rail. I checked the metal rail and the hose connector. I replaced all replaceable parts. Check all seals. And bleed properly.

So the main issue is the lack of returning fuel after the injector pipe union. Does this mean my injectors are clogged? Is there a way to clean them myself? I have already added heavy duty injector cleaner to the Jerry can.

[GrowleyMonster]

Originally Posted by SailnParadise

I changed the fuel return hose and checked the secondary filter. I am bypassing the tank and Racor via 5g Jerry Can. I am getting solid fuel from the injector pump. And fuel squirting then I crank with injector cracked. But I am getting no fuel from the return fuel rail. I checked the metal rail and the hose connector. I replaced all replaceable parts. Check all seals. And bleed properly.

So the main issue is the lack of returning fuel after the injector pipe union. Does this mean my injectors are clogged? Is there a way to clean them myself? I have already added heavy duty injector cleaner to the Jerry can.

Something odd is going on with your injector pump is how I see it.

[skipperpete]

GrowleyMonster, thanks for that TADiesel link, it should be compulsory reading for all Perkins 4-108 owners…. Or anyone who has a Delphi, or Lucas CAV DPA injector pump on their engine.
The OP mentioned loosening the nut “on top of the injectors” … that serves no real purpose, its only the injector leakoff. Its the nut that connects the injector pipe to the side of the injector that you’re hoping to see fuel popping out of….only while cranking , only with the stop control fully in the run position
…… no fuel here, no hope of a start.

[SailnParadise]

Originally Posted by skipperpete

GrowleyMonster, thanks for that TADiesel link, it should be compulsory reading for all Perkins 4-108 owners…. Or anyone who has a Delphi, or Lucas CAV DPA injector pump on their engine.
The OP mentioned loosening the nut “on top of the injectors” … that serves no real purpose, its only the injector leakoff. Its the nut that connects the injector pipe to the side of the injector that you’re hoping to see fuel popping out of….only while cranking , only with the stop control fully in the run position
…… no fuel here, no hope of a start.

Fuel does spit out of the unions when cranking.

But I'm not getting any fuel in my return line. Shouldn't I be continuously getting a slow stream back into my jerry can?

[SailnParadise]

Originally Posted by GrowleyMonster

Elevate the jug higher than the engine. This ensures that the system fills with fuel and not air. Meanwhile look for any fuel seepage from connections. That will be where air is getting into the system in normal operation.

You might want to change the engine mounted fuel filter. Be absolutely certain the gasket is libricated with a little clean grease and the filter fills up with fuel and there are no leaks.

https://tadiesels.com/assets/docs/te...20Changing.pdf
That is a good reference for you. Notice on page 5 the illustrations of the two common fuel pumps used. Be sure you are bleeding at the correct screw. Should take a 5/16" wrench.

When you bleed the injector pump, if it is operating correctly, if there is all fuel and no air coming out the bleed port, then fuel should be coming through the return line and through the injector lines. Verify, re-verify, triple verify before you start spending money on a mechanic. Finally check the anti-stall device as per the above document, and make sure that the fuel shutoff is not shut off and the throttle arm can move freely when the control cable is disconnected. This might be hard to get at.

I haven't messed with injector pumps and most owners will have a mechanic check, repair, rebuild, replace, or re-install the injector pump. It can be done wrong a lot more ways than done correctly.

Thanks for this!

[SailnParadise]

The stall happened due to clogged primary filter. Secondary was only a month old and had 2 racors installed before. So nothing should have gotten into the pump. What issues cause lack of returning fuel

[GrowleyMonster]

Either you are not fully understanding instructions and your manual, or something is wrong with your injector pump. No offense, cause sometimes I don't understand stuff either, and either I get it eventually or not. But it seems like somehow somewhere there is possibly a communications gap. Or else your injector pump or some associated part is kaputt or out of adjustment. You may have to just grit your teeth and call a mechanic who is familiar with marinized Perkins diesels. I can't think of any possible and practical troubleshooting procedure that has not been suggested. As something of a beginner I would not try to remove or work on the injector pump other than bleeding, which is normal user level maintenance.

[skipperpete]

GrowleyMonster is correct... again.
It really sounds like a pump problem but I’m puzzled by the claim that fuel is visibly spurting at the injector high pressure connections ...... I’m just about of ideas here but I’ll take one last crack at it. First off, I’d pull out an injector and connect it to the HP line, put a plastic bottle over the nozzle and nozzle body and start cranking. You should see the injector spraying atomised fuel at the bottom of the bottle, if not, ya found the problem, low hp fuel pressure. If YES, start taking a good look at the intake and exhaust systems for blockages cos if you have atomised fuel and compression there should be fire.... dpa pumps generally don’t lose the timing and still function.
I’m assuming its not sub zero where you’re at and you DO have compression.
This next bit is probably NOT the problem or part of it since you actually have fuel at the injectors but I’ll mention it anyway.
Where the feed line enters the injector pump there’s a regulating valve and a tiny shuttle valve whose only purpose in life is to direct priming pressure around the vane pump to purge the air from the pump, as soon as that shuttle senses vane pump pressure ( cranking) it blocks the port and generally the engine gets regulating valve pressure to fill the hydraulic head plungers, injection happens and mostly the engine starts...... unless there’s no heat from compression or no air (oxygen).
That’s my last idea.... good luck with it.

[deblen]

This may help https://www.cruisersforum.com/forums...-200941-3.html

[Shaneesprit]

Lack of return fuel can only be lack of fuel flow in the first place,
reading this thread, I would suspect the Electric lift pump, of feeding you air into the system.
Remove it and just use your priming bulb - temporarily.

Running from a can right next to the engine rather than the tank is a good idea while you figure out the issues.

Provide photos here of your system. It will be easier for people to understand your issues.

[SailnParadise]

Originally Posted by Shaneesprit

Lack of return fuel can only be lack of fuel flow in the first place,
reading this thread, I would suspect the Electric lift pump, of feeding you air into the system.
Remove it and just use your priming bulb - temporarily.

Running from a can right next to the engine rather than the tank is a good idea while you figure out the issues.

Provide photos here of your system. It will be easier for people to understand your issues.

Ok. I will take out the electric pump for now. And add a few photos of my setup.

[SailnParadise]

Looks like theres a fuel restriction somewhere inside the hp pump. I get fuel at the primary bleed screw on the pump body. But less at the bleed screw on top of the anti seize valve. And none at the union to the injectors. I confirmed this with the electric pump installed and without. Seems a real pain to uninstall to get serviced. Any way to confirm this?

[SailnParadise]

Could the Anti Seize valve be too tight? Maybe I accidentally tightened it when I bleed it when it first stalled. Does the anti seize valve increase and restrict fuel flow? If so that could be why the fuel movement stops after the valve