Just replaced IP diaphragm and think i messed up?!

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If you do indeed have a problem with air entering (as you suspect) Dan, when you get home I wouldn't expect you to be able to run your cruiser without bleeding it out first. (Or perhaps it may start and run briefly before stalling and refusing to restart without bleeding.)

I say this, because by the time you get home, the air would have had a lot of time to accumulate to "an engine-stalling quantity".

And I think the air is far more likely to enter from somewhere up high upstream of your fuel pump... like the bleed line running from your injectors back to the fuel pump inlet. This area will be sitting under significant vacuum now as the fuel wants to gravitate back into your tank.

On the other hand, your fuel-pump-inlet-strainer is down low enough that it is probably under a slight positive (ie above-atmospheric) pressure. (So fuel is likely to leak out there rather than air getting sucked in.)

The check valves in your fuel pump should hopefully prevent your fuel filters being subjected to vacuum.

When you fire it up, a slug of air will move into your injector pump and once there ....fuel injection will cease.

And if the bleed line is indeed leaking, the most likely place is that short length of small-bore rubber hose (and associated hose clips) at the top LH rear corner of your engine by your inlet manifold.

Cheers
Tom

PS. If your primer pump drips any fuel at all when you use it - replace it with a Bosch unit. (You can get one ex HongKong from Aussi eBay for $25 delivered ... last time I looked.)

And I'm going away for a few days without access to the Internet .................So I'll check how you're going when I get back.
 
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Quote"check the priming pump housing where the inlet strainer is". There have been numerous posts regarding air leaking into the system thru the priming pump.I bet this is the culprit
 
Quote"check the priming pump housing where the inlet strainer is". There have been numerous posts regarding air leaking into the system thru the priming pump.I bet this is the culprit

Hi Joe, I replaced the priming pump with the Bosch unit late last year and it does not leak at all. I just keep the OEM plastic cover on it to hide it because i can. :)
The pump i removed must have been original, because it pi$$ed out fuel the first time i changed fuel filters and tried to prime the system!
I think i've possibly upset the sealing faces on the inlet banjo fitting when i removed the inlet strainer....possibly.:confused:

Argh, 4 more days away until i'm home to mess around with it...
 
Not sure if you blead the IP? I ran out of fuel once and the manual said to bleed it first then work your way up.
P8290021[1].webp
 
Alrighty, i'm tearing my hair out! :bang:

I got home on Friday and since then I've:
-replaced both fuel filters again,
-replaced the fuel supply hose going from the solid line to the priming pump inlet,
-Took out the priming pump inlet strainer, checked it and reinstalled, making sure all the fittings were sealing.
-Cleaned the venturi in the throttle body.

The cruiser starts ok now, and idles great but still does not have full power. It seems to have a small amount of more power than last time, but it's still not like it use to be. It was slow before, but this is ridiculous!

What else could i check?! The diaghragm is fitted correctly. The EDIC and EDIC arm are fitted correctly and working. I had the bosch priming pump fitted for ages now and that works great and doesn't leak.

Could a new diaphragm be tighter and not allow as much movement of the rack as the old original one i removed?? Should i turn the fuel up a bit maybe and see what that does??

Thanks for your help so far gents, but I'll tell ya i'm getting close to lighting a fire under it! :bang:
 
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.... I took the inlet hose off and i have full movement of the butterfly .....

Are you really sure about this Dan?

You had someone press the accelerator pedal and then checked that the butterfly valve was vertical (wide open)?

:cheers:
 
Did you ever get back inside the diaphragm cover? It seems since thats what you changed then thats the best place to look for trouble.

Beyond that, why not try pulling the fuel supply hose off and running the truck from a pop bottle full of diesel fuel?

Maybe even a bottle of seafoam, perhaps there is some gunk that needs dissolving?
 
Take the EDIC arm off of the IP. Start the vehicle and manually move the arm to the over-inject position. The RPMs should increase. If they do increase I'd adjust the fuel screw and see if things improve.

I just spent some time looking at the injection pump section of the 3B FSM. There are no photos where the EDIC lever is off of the pump. They tear down the entire pump assembly and never remove that arm or mention removing it. It's hard to tell from the diagrams how it interfaces with the fuel metering rack.

It sounds like something is limiting the mechanical governor. It's in the lower half of the governor housing below the diaphragm. Did you tinker with the long nut sticking out of the lower portion of the housing?
 
SUCCESS!! :D

I hit the garage hard this morning, armed with my B engine manual, determined to fix this problem. I took the diaphragm cover off again and then disconnected the EDIC arm from the EDIC motor. I played around it with it for ages, just moving the fuel rack back and forward and seeing how it was coupled with the connection to the EDIC arm. I played around with moving the "overinjection magnet" position (i think that is what it is called) that has a spring working on it to move the EDIC arm tab into the run position once the engine has started.

I did cut the lockwire and unscrew that magnet fully two weeks ago and when i set it up last time i had it aligned so that the EDIC arm was within the two marks, both at the EDIC motor and on that tab. What i did today is unscrew that magnet a bit more so that when the EDIC goes to the "run" position it has the fuel rack in a slightly higher position. The EDIC arm is aligned just within the two marks on the tab, so it's all in spec. It's amazing how such a small movement can have such a big effect. When i was adjusting it with the engine at idle i found this "sweet-spot" and locked it off there. It now idles great and has it's power back. I use the term "power" loosely, haha, but i'm happy to have sorted it out! :lol:

I'm a pro at getting to the diaphragm now! I can get at with the EDIC in position and connected, but damn I don't want to play around down there for a long time now. I'm getting new tyres tommorrow and i just want to drive the damn thing. :steer:

Thank-you everyone for all your advice and ideas, it was much appreciated.
Beers to all of you! :beer:
 
SUCCESS!! :D

:clap:

... I played around with moving the "overinjection magnet" position (i think that is what it is called).....

Which magnet did you unscrew? Just curious for future people that might have a similar problem and find this topic.

AFAIK "an overinjection magnet" is an ALTERNATIVE to "an edic system" so you shouldn't have one at all there Dan. (I believe it uses a simple electromagnet to pull the IP lever into the overinject position rather than using the motor/gearing/rod of your EDIC system.)

You really mean you tampered with this don't you Dan?

InjectorPumpFullStopCapsule1.webp

The FSM calls it a Full Stop Capsule but I've always thought they meant to say "Fuel Stop Capsule". (But most of us just call it "the fuel screw".)

:cheers:
InjectorPumpFullStopCapsule1.webp
 
:clap:





AFAIK "an overinjection magnet" is an ALTERNATIVE to "an edic system" so you shouldn't have one at all there Dan. (I believe it uses a simple electromagnet to pull the IP lever into the overinject position rather than using the motor/gearing/rod of your EDIC system.)

You really mean you tampered with this don't you Dan?

View attachment 449927

The FSM calls it a Full Stop Capsule but I've always thought they meant to say "Fuel Stop Capsule". (But most of us just call it "the fuel screw".)

:cheers:

Yes, thanks Tom, that is the one. In my manual it shows it with a wire attached and mentions overinjection magnet a lot, so yeah it must be an electromagnet on other engines....2B maybe?
I removed it totally two weeks ago and when i reinstalled it i must have screwed it in just a bit too much. Like i mentioned, it's amazing how much of a difference a small adjustment to that can make.

You said it's commonly called the "fuel screw", but what about the adjustment screw below the diaphragm cover? Isn't that one used to turn the fuel up?
 
... what about the adjustment screw below the diaphragm cover? Isn't that one used to turn the fuel up?

I think you're referring to the "Maximum engine RPM" screw now Dan:

MaxSpeed.webp

:beer:

s*** 41000 rpm for my B-diesel! Must be yet another Toyota typo! I'll have nightmares now!
MaxSpeed.webp
 
A half turn on the fuel screw will make a big difference in the amount of fuel delivered. If you hook up a pyrometer to the exhaust you will see that even a quarter turn on the fuel screw could mean 50 degrees difference in exhaust temps.

The screw sticking out below the diaphragm cover adjusts the mechanical governor in injection pump. You generally don't adjust it. These injection pumps have both vacuum and mechanical governors acting on the fuel rack.
 
Thank, same issue for me, just bought it, bj75 and the PO told me he had changed the diapragme and said he as playing with this ajustable screw???.....Take the truck on an 500km road trip to my home, heeeee i knew this engine was not so powerfull but !!!! some times on the 4th but forget the 5 speed, and oh yes there is hills everywhere....always on second gear and sometimes on the first!!!. So glad i found your thread, thank a lot.
Justin
 
i love the factory 12v light, way to keep rocking it, cheers!
 

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