3B reving high again?

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I believe I already asked this question and got some response. When I first start my BJ42 it revs around 900rpm but after driving it a little it stays around 1300-1500 rpm? any idea, and is it something I can replace? any part numbers?thanksRoberto
 
Hey Roberto
Do u mean it idles at 900 rpm ? Mine idles at about 650 when warm.
I remember your old thread on this. Did u get it fixed and it started happening again?
 
diaphragm....

should idle at 650 or so.
 
How much to replace the diaphram and where can I get parts? That is the part others were saying needed fixing in my last post? what does it look like and where located?Roberto
 
Diaphragm

Denso part#090580-0041 Should be around ~$35 Canadian.
Dealer Toyota part#22303-47010 around ~$120 Canadian.
Exact same, I had both.

If you are really stuck and can't locate one, I could send you one from a local diesel shop.

Cheers, Edgard.
 
Also a repair tip (I read a thread about it, some people cursed the whole ordeal), I did mine at minus 15 Celcius outside, and my experience has been two people are better at it than one, and either way it's a witch (I think it was designed to be replaced with the injector on a bench). I was reaching from underneath the car, and my mechanic reaching out from the engine compartment. Rip the old one out, then proceed in taking it apart, this is the treat part. Lots of room, then to reinstall
you have the option of the little/tiny nut or the cotter pin. I suggest the cotter pin, and replace the stock cotter pin with something a bit more "humane".i.e. Longer. That way, you have better access to pry it open once in place.

In hind site you may even be able to thread the cotter pin in the hole. However, I was not that imaginative at sub zero :) .

Hope it helps.
 
Thank you for the insight, I will be ordering the part so I can get this fixed soon.
 
Does anyone know if that is the same part for a 78 B diesel? I am experiencing the same problem.
 
your local dealer should be able to cross reference the part# or at least give you the number for your truck and you can cross reference it with the numbers above. The VIN# will reveal it all. If you can't, send me your VIN and I will inquire the dealer here.

Hope this helps.
 
Diaphragm absolutely for sure. Identical to the symptoms on mine. The part from Toyota is about $80, and from a diesel shop that sells Denso, $16.

The job itself is the hard part. Imagine trying to tickle your right elbow with your right hand while your forearm is leaning heavily on a sharp fork.

Good luck.

Craig.
 
The part from Toyota is about $80, and from a diesel shop that sells Denso, $16.

.

Exactly.... do not buy this part from Toyota. Or other high priced re-sellers. Buy from an injection shop.

I paid 20 bones in Prince George, at PG fuel injection.
 
it looks like this:
DSC04249.JPG


and you'll probly get a bit of oil come out when you undo the cover/take it out..

check it out in the FSM for the process and it'll help. I did it on the truck and it was just a bit fiddly.
 
well a friend of mine owns a diesel shop, and i have the same problem, revs damn high, i was told to retard the injecter timing about 5mm.


ill try that and if it doesnt work ill get a new diaphram? does it have to be a toyota specific diaphram or just one that fits my pump?
 
Confirming your diaphragm is faulty

Diaphragms fail through developing a tear and leaking. (They're supposed to be replaced automatically every 60,000kms as part of routine maintenance.)

Fortunately there is a VERY simple test you can do to confirm if the diaphragm is leaking. Just suck on this hose (after disconnecting it from the intake manifold venturi):

diaphragm1.webp

You can see from this photo that the hose you should suck on (labelled "vacuum side") is normally connected to a venturi device in the intake manifold. The suction developed by the venturi moves the rack in the injector pump via the diaphragm. And you can also see how the other side of the diaphragm is connected to aircleaner-side of the throttle butterfly-valve (approx atmospheric pressure):
butterfly.webp


Oops- Forgot to mention that you suck on the hose to see if it holds vacuum. -----I just did this on mine (to remind myself how easy it is) and I could very easily tell by my mouth that my diaphragm was "sound" and not leaking at all.

It should feel like you're sucking on a blocked tube. If you feel air entering your mouth --- It's knackered!

:cheers:
diaphragm1.webp
butterfly.webp
 
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Does anyone know if that is the same part for a 78 B diesel? I am experiencing the same problem.

YES!

(My 1979 B diesel uses the Denso 090580-0041 diaphragm.)

:cheers:
 
well a friend of mine owns a diesel shop, and i have the same problem, revs damn high, i was told to retard the injecter timing about 5mm.

I wouldn't be doing that. Diesels rarely need a timing adjustment but the 3B does occasionally need an injector diapragm replacement.

But then what do I know having had several 3B engines?
 
ohrly .... I agree with lost marbles and cruiser guy ... retarding the injector might resolve it for a bit but if the diaphragm tears some more it will rev higher again and then what do you do? Definitely a diaphragm replacement
 
100% agree cruiser_guy, the only time I had to adjust the timing on my 3B was when I rebuilt the engine and had the pump off.

That was in 400,000 kms.

Craig.
 

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