3B diaphragm replacement (2 Viewers)

[lowenbrau]

I'm not clear on that .. it not only allow more fuel at higher alt .. coz I turn up my fuel there and im at sea level .. so it need to do something else in the hole range of fuel ..



Thanks .. clear as mud ..

How did you turn up your fuel? By spinning the HAC, correct? Spinning it away from the "stop' lever?

 

[Tapage]

How did you turn up your fuel? By spinning the HAC, correct? Spinning it away from the "stop' lever?

Gotcha ! sorry was a long day yesterday here at the office ..

 

[eric2381]

Hello, thanks to everybody for the great info. I have recently bought a 1982 BJ60 with the 3B, and it shows the symtoms of needing a diaphram replacement. I notice people have been listing the part number, does anybody know of a place to order one, through the web? I'll check around town with the parts guys I deal with, but any help is greatly appreciated. Thanks, Eric

 

[eric2381]

Hello, again. I looked around the site a bit more and found what I was looking for. 4wheelauto.com had the part I was looking for. Thanks, and I'll check back for more info, and hopefully help someone out myself, Eric

 

[lostmarbles]

Hello, again. I looked around the site a bit more and found what I was looking for. 4wheelauto.com had the part I was looking for. Thanks, and I'll check back for more info, and hopefully help someone out myself, Eric

Glad you found one alright Eric.

They seem to be very readily available. (I got my last one from a local diesel service shop.)

 

[eric2381]

Hey everybody. I just changed the diaphram on my cruiser. The motor is running alot better. The idle is back down to normal, and it doesn't put out a huge cloud of smoke when it's running. I really appreciate the help of this forum, without the info found here, I would've had a headache. With the help it wasn't too bad. Thanks again, Eric

 

[eleblanc]

And here's another photo that would be a good addition to this thread and my earlier reference to "sucking on a hose" to test your diaphragm:

View attachment 213419

I'm going to have to check but your hose are crossing each other, doesn't seem to be that way on my truck.

 

[Tofudebeest]

I had no idle issues, nor black smoke (just the familair white/gray at start-up, virtually nothing once warm, but my IP gasket where the diaphragm is, is leaky. I was told to replace the diaphrams and gasket, but have not yet done so. Was I misled?

 

[lostmarbles]

I'm going to have to check but your hose are crossing each other, doesn't seem to be that way on my truck.

Don't worry. I think the crossed-hoses could be unique to the B-engine.

I remember discovering previously that other people's hoses don't necessarily cross over each other (but their set-ups still work the same as mine).

I had no idle issues, nor black smoke (just the familair white/gray at start-up, virtually nothing once warm, but my IP gasket where the diaphragm is, is leaky. I was told to replace the diaphrams and gasket, but have not yet done so. Was I misled?

I seem to remember there is no separate gasket there and that the "diaphragm assembly" itself serves as the gasket. So if you want to stop the leak, then it could be wise to replace the diaphragm at the same time.

I guess it is difficult to tell whether it is "neatsfoot oil" or "engine oil" that is leaking out because both will be "black" from my experience. (Old neatsfoot oil turns black.)

My diaphragm housing used to have "dirty oil stains" around it at the joint but it is reasonably clean now:



When it was "oozing" - I don't recall any problems associated with it.

So my answer is - If you want to stop the leak - Yes - Change the diaphragm (and perhaps apply some sealant to ensure you get an oil-tight seal)



By the way - There is a drainplug there to drain engine oil (that leaks into there) from the compartment on the injector-pump side of the diaphragm (as I suppose you already know).

 

[eleblanc]

And here's another photo that would be a good addition to this thread and my earlier reference to "sucking on a hose" to test your diaphragm:

View attachment 213419

Lostmarbles, your hose are not installed correctly according to the manual.

 

[lostmarbles]

Lostmarbles, your hose are not installed correctly according to the manual.

Mine is a 2977cc B engine rather than a 3431cc 3B engine.

Looks like they moved the positions of the "venturi" and "reference" connections on your engine's intake manifold so your hoses don't need to cross over each other.

 

[GoatboyNZ]

hey where did you get one in NZ? repco? toyota dealer? thanks for your help so far. its priceless

 

[lostmarbles]

hey where did you get one in NZ? repco? toyota dealer? thanks for your help so far. its priceless

"Diesel & Turbo" in Wellington. They do all sorts of specialist diesel servicing/repair work down here and stock Denso parts. So you need to find a similar place in Auckland. (I don't think Diesel & Turbo have a branch in Auckland.)

Doing a search with Google - perhaps try Diesel Services Ltd 120 Penrose Rd. (Call them armed with the Denso part number 090580-0041.)

Cheers
Tom

PS. Repco might be able to help you but others should be cheaper. (And I've never connected Repco with "supplying diesel parts" so I've never tried them myself.)

 

[Sykoslug]

Here's a puzzler, idle speed has been up around 900rpms, just noticed recently. I adjusted it down to roughly 700 with idle speed adjustment protocol. But it reminds me of a recent trip to 10,000 ft elevation, my idle went way up to 1200 rpms or so! It seems that the thinner air would necessitate this increase- or might a diaphragm leak be accentuated by the altitude increase?
My 3b has been turbo'd and has no HAC. There seems to be some diesel seepage on the lower right side of the IP that I never looked for before...No other obvious defects(no smoking, choking, dying, hard starts,racing,etc.)

Do I bother taking the diaphragm cover off? And inspecting?

 

[lostmarbles]

Here's a puzzler, idle speed has been up around 900rpms, just noticed recently. I adjusted it down to roughly 700 with idle speed adjustment protocol. But it reminds me of a recent trip to 10,000 ft elevation, my idle went way up to 1200 rpms or so! It seems that the thinner air would necessitate this increase- or might a diaphragm leak be accentuated by the altitude increase?
My 3b has been turbo'd and has no HAC. There seems to be some diesel seepage on the lower right side of the IP that I never looked for before...No other obvious defects(no smoking, choking, dying, hard starts,racing,etc.)

Do I bother taking the diaphragm cover off? And inspecting?

I would test the diaphragm (using your mouth on the vacuum-side tube) to see if it holds a vacuum.

Only takes a minute and it is dead easy to do. That'll tell you if your diaphragm is leaking or not.

 

[Sykoslug]

I would test the diaphragm (using your mouth on the vacuum-side tube) to see if it holds a vacuum.

Only takes a minute and it is dead easy to do. That'll tell you if your diaphragm is leaking or not.

Roger that I will give it a shot.
I do recall reading that earlier in the thread... Got too caught up with all the other anatomy and physiology of the Injector Pump/Venturi Complex.

Any thoughts on the Altitude related idle rpm increase?

 

[lostmarbles]

...Any thoughts on the Altitude related idle rpm increase?

Sorry. I have no experience of this. Maybe our mountains aren't high enough

 

[Sykoslug]

Ok, new problem ;! My line won't hold a vacuum- I disconnected the one that connects to the external side of the diaphragm - it would be on the right if you faced the engine from the drivers side. I tested with the motor shut off, and it didn't hold at all. It was a bit tricky getting my face close enough to test.

Also, the pump itself is leaking oil after a 6 hour drive *Arggggghhh* I read somewhere here that there is a specific screw which could be used to drain oil from the pump- can any body tell me which screw?

And why would it be leaking oil?! What else do I need to be concerned with?

Thanks for any help!

 

[lostmarbles]

.. My line won't hold a vacuum- I disconnected the one that connects to the external side of the diaphragm - it would be on the right if you faced the engine from the drivers side. I tested with the motor shut off, and it didn't hold at all. It was a bit tricky getting my face close enough to test. ...

Odd! (If I remove the intake-manifold-end of that hose on my BJ40 it is within easy reach - but then I'm skinny and lanky.)

Yes. you've got the correct side of the diaphragm (where the vacuum acts).

By the way, I forgot to say that you should always suck gently with your mouth and never use your lungs to do it. And I find it easy to feel if there is a leak this way whereas using your lungs would be more difficult and pose the danger of getting something bad in your mouth (if it happens to be in there). ,,, Bit late for that advice now though!


So it sounds from this that you do indeed need to replace your diaphragm.

...Also, the pump itself is leaking oil after a 6 hour drive *Arggggghhh* I read somewhere here that there is a specific screw which could be used to drain oil from the pump- can any body tell me which screw?

And why would it be leaking oil?! What else do I need to be concerned with?

Thanks for any help!

Well I think ANY oil leak is something to be concerned with. (You should at least know EXACTLY where it is coming from.)

So I would pin-point the source ASAP.

In other words, I advise finding the source of that leak BEFORE you attempt to replace the diaphragm. And I say this because:

• the oil leak may be caused by your diaphragm housing being loose (and fixing that may overcome your vacuum leak without you needing to replace your diaphragm), and
• You will be disturbing things in the same area when you do the diaphragm replacement. So to avoid confusion, fix one thing at a time and keep jobs separate - if you know what I mean. (I'm finding it hard to put what I mean into words.)

And here is a thread showing some drain plugs (for engine-oil that gets through the seals to sit on the IP-side of the diaphragm):

https://forum.ih8mud.com/diesel-tech-24-volts-systems/193714-1st-oil-drain-30-years.html




PS. If you take a photo of the leak - perhaps we can help more with ideas on the cause. (And is the leak oil or diesel - because originally you said "diesel"?)

 

[Sykoslug]

Marbles,
Thanks for the quick reply!

So after a second glance with another pair of considerably more skilled eyes it appears that the diaphragm cover was leaking oil (perhaps motor- perhaps neatsfoot)- I rechecked vacuum after tightening (4 flathead screws- .75-1.25 turns each) and there was an improvement but its a little hard to tell if the seal is perfect or not. Also, my idle went down closer to 650. I think I will drive it as is and pursue a vacuum gauge and keep an eye on the leakiness.

If I can get a picture sent I will do that.

Cheers