injection issues

[X344chap]

Did you ever get it going? I've just put new liner and piston in a 444 I got off ebay, but can't get it to quite run. Fitted new injectors but I think fuel pressure is too low to open injectors properly! Barely runs for few seconds then dies!

When you say barely runs - does it crank over fast enough and are you getting smoke from the exhaust? Are you using starting fluid - or using the heater plugs and have you checked these are working. The B series engines will not start off the key without a good heat. btw i have a 444 as well - like yours it needed a couple of liners as it had been full of water.

 

[JeremyD]

Fitted new Mercedes type heater plugs so much more powerful than the originals that weren't working when I first tried to start it. I suspect too much ez start has been used in past as when I took the cylinder head off one of the pre combustion chambers was broken in half and hitting a piston!. If I jump start to get quicker cranking speed it just about runs on one cylinder lots of white smoke from exhaust. It never picks up on throttle or multiple cylinders just conks out as though not enough fuel?

 

[X344chap]

Fitted new Mercedes type heater plugs so much more powerful than the originals that weren't working when I first tried to start it. I suspect too much ez start has been used in past as when I took the cylinder head off one of the pre combustion chambers was broken in half and hitting a piston!. If I jump start to get quicker cranking speed it just about runs on one cylinder lots of white smoke from exhaust. It never picks up on throttle or multiple cylinders just conks out as though not enough fuel?

Lots of white smoke says plenty of diesel - but maybe not at every injector or maybe not at the right time and maybe with not enough compression/heat to ignite it. You sound as though you are handy on the the tools - so apologies if i'm stating the obvious - but slacken an injector one at a time and see if you can identify if its firing on one cylinder and bleed the lines to the injectors again. I'm guessing you have never seen this running and its been a non runner for long time? It could have some underlying problems. At this point i'd be giving it a sniff of ez start to see if it picks up and if it does then i'd be having a look at the injectors to see if they are all popping off and not stuck or blocked. Make sure if you do this you are spraying into a tin can - dont put any body parts near an injector nozzle. Just re-read and you have fitted new injectors - try the old ones.....

 

[X344chap]

Lots of white smoke says plenty of diesel - but maybe not at every injector or maybe not at the right time and maybe with not enough compression/heat to ignite it. You sound as though you are handy on the the tools - so apologies if i'm stating the obvious - but slacken an injector one at a time and see if you can identify if its firing on one cylinder and bleed the lines to the injectors again. I'm guessing you have never seen this running and its been a non runner for long time? It could have some underlying problems. At this point i'd be giving it a sniff of ez start to see if it picks up and if it does then i'd be having a look at the injectors to see if they are all popping off and not stuck or blocked. Make sure if you do this you are spraying into a tin can - dont put any body parts near an injector nozzle.

Another stupid question - when you fitted the mercedes heater plugs - you did change the wiring to remove the pepper pot resistor and the plugs are wired in parallel? You cant just swap the heater plugs and use the old wiring. If the engine isnt heated it just wont start and you will get the white smoke symptoms.

 

[JeremyD]

Another stupid question - when you fitted the mercedes heater plugs - you did change the wiring to remove the pepper pot resistor and the plugs are wired in parallel? You cant just swap the heater plugs and use the old wiring. If the engine isnt heated it just wont start and you will get the white smoke symptoms.

Not seen it running. Was told it was running when the chap I bought it off had it, but then stood for years outside I think so who knows! Glow plugs working well glowing red hot, I bypassed the original pepper pot resistor. Will investigate further when get chance. The new injectors I fitted I adjusted the spring tension exactly the same as ones I removed which were blocked rusty etc. Guessing you need proper equipment to adjust crack pressure? But guessed it would be better than the knackered injectors fitted.

 

[X344chap]

Not seen it running. Was told it was running when the chap I bought it off had it, but then stood for years outside I think so who knows! Glow plugs working well glowing red hot, I bypassed the original pepper pot resistor. Will investigate further when get chance. The new injectors I fitted I adjusted the spring tension exactly the same as ones I removed which were blocked rusty etc. Guessing you need proper equipment to adjust crack pressure? But guessed it would be better than the knackered injectors fitted.

About £55 for an injector pressure tester.
https://vevor.co.uk/products/diesel...A8cn5bj3k80ZgyleeAG5Oy_89m8J3G9xoC1mEQAvD_BwE

You cant really set them correctly by guessing the spring tension - but tbh i've had engines running after stripping down the injector and guessing the number of turn on the screw. If there's lots of white smoke then diesel is flowing through the injectors - give it a puff of quick start and see what happens. I'd also have the exhaust manifold off it to look into the exhaust ports in the head to see which cylinders are producing the white smoke. Did you go through the head when you had it off and do the valves and seats and got the valve clearances right? A cheap compression tester is handy as well - you can screw it into the heater plug holes and crank it over with the strangler pulled.

CAV Model DPA rotary style injection pump, Injector opening pressure = 2350 to 2450 psi.

23.0:1 compression ratio. Compression = 445 to 470 psi @ cranking speed.

 

[JeremyD]

I will try what you have said many thanks. Valve seats all looked good and re set tappets accordingly.

 

[aidan]

About £55 for an injector pressure tester.
https://vevor.co.uk/products/diesel...A8cn5bj3k80ZgyleeAG5Oy_89m8J3G9xoC1mEQAvD_BwE

You cant really set them correctly by guessing the spring tension - but tbh i've had engines running after stripping down the injector and guessing the number of turn on the screw. If there's lots of white smoke then diesel is flowing through the injectors - give it a puff of quick start and see what happens. I'd also have the exhaust manifold off it to look into the exhaust ports in the head to see which cylinders are producing the white smoke. Did you go through the head when you had it off and do the valves and seats and got the valve clearances right? A cheap compression tester is handy as well - you can screw it into the heater plug holes and crank it over with the strangler pulled.

CAV Model DPA rotary style injection pump, Injector opening pressure = 2350 to 2450 psi.

23.0:1 compression ratio. Compression = 445 to 470 psi @ cranking speed.

Some good info there, I have a rebuilt Perkins had a mild but steady stream of white smoke from it last week running and starting perfectly but for the white smoke.

It’s not using water.

smoke has vanished this week, could injector be intermittently faulty

 

[Timbo]

CAV rotary. Filter clean, vanes on first stage rotor look OK. Lift pump supplying plenty of fuel just not injecting
Unfortunately I'm at the stage where I must continue because of the time and money spent already otherwise it could go back into the friggin hedge.

Get pump rebuild. Will have stuck from being stood with old diesel in it.

 

[X344chap]

Get pump rebuild. Will have stuck from being stood with old diesel in it.

I think you are replying to the OP - mikep - who hopefully sorted the problem out in 2019 - its JeremyD who is now asking questions about his 444.

 

[JeremyD]

Have taken pump to dieselec at Ditton Priors to be rebuilt, virtually no fuel output from it.

 

[jrsavoie]

If it has an inline pump, take the side plate of and see if the rack is moving freely throughout its full travel. If it's a rotary cav pump, there should be a filter under the fuel inlet pipe fitting. Could be dirty and not letting enough fuel through.

Same issue here.

1975 Ford 3550 diesel backhoe with cav pump

I removed the inlet fitting and expected to see a screen.

There was a spring there. I pulled the spring out and looked as best I could. Everything looked clean.

Does the spring sit inside of the screen?

I stuck the spring back and reassembled

Thanks

 

[agrimax]

The inlet filter,if still fitted, sits around the outside of the hole that the spring drops down into.If it's there,you can only see the top edge of the filter unless you suck the diesel out of the hole. It needs to be very carefully fished out with a fine hook or pick so as not to bring out the delivery valve components with it. It's not a big issue but if they do come out,they must be reassembled in the correct order,especially the small piston that usually ends up at the bottom of the hole and needs lifted out with a very small magnet...