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What's the cause of them ripping besides age?
The diaphragm is leather so any long term exposure to motor oil or diesel will cause it to deteriorate.
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What's the cause of them ripping besides age?
Lynchmob thanks for this post, most useful. I do have a question though after reading it. When you install new diaphragm do you have to lube it with something? I remeber reading somethng about Neet's foot oil, or something like that, being leather it must need something, or maybe I am way off here.
cheers,
cruise diesel
So, not to completely hijack this thread or anything but I was just wondering if the fact that the injector pump on my 3b is pissing diesel all over my bottom end has anything to do with a torn diaphragm? Ideas?
Let me answer that for Lynchmob if I may.
The diaphragm comes "prelubed with neatsfoot oil" and is nice and soft. So there's no need to apply anything during installation. (Just keep engine oil and dirt off it as you install it.)
It is actually sold in a sealed bag with the neatsfoot as this photo shows:
View attachment 232076
To keep it nice and soft after it has been installed - Just add a couple of drips of neatsfoot through that "application hole" in the top of the diaphragm housing every time you change the engine oil.
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I noticed the dates on your iud boxes to have a difference of 14 years. Did you replace them for preventative maint. or did the diaphram give up the ghost? I just replaced mine (PITA) which had a hole in it, RPM's over 1000 but no smoke. It appears that mine was original which would make it 24 yrs. old 170000 K. Not bad for a constantly moving peice of leather.Let me answer that for Lynchmob if I may.
The diaphragm comes "prelubed with neatsfoot oil" and is nice and soft. So there's no need to apply anything during installation. (Just keep engine oil and dirt off it as you install it.)
It is actually sold in a sealed bag with the neatsfoot as this photo shows:
View attachment 232076
To keep it nice and soft after it has been installed - Just add a couple of drips of neatsfoot through that "application hole" in the top of the diaphragm housing every time you change the engine oil.
![]()
I noticed the dates on your iud boxes to have a difference of 14 years. Did you replace them for preventative maint. or did the diaphram give up the ghost? I just replaced mine (PITA) which had a hole in it, RPM's over 1000 but no smoke. It appears that mine was original which would make it 24 yrs. old 170000 K. Not bad for a constantly moving peice of leather.![]()
Well the air-intake butterfly would still have some control over the engine rpm - but only through varying the engine's air supply.
The fuel would never move away from the "maximum pedal-to-the-floor" setting.
(Very smokey I would imagine and it certainly wouldn't idle smoothly or at the normal revvs.)
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...If you look closely at the profile of the throttle body, you should see that the tubes connect to the venturi at different heights. .............
... This is because as the butterfly opens and closes, the available vacuum in the venturi rises and falls............
..From what I have read from your posts the spring pushes the diaphram rod towards rich, so the lower venturi "signal" hose should connect to the diaphram housing on the same side of the spring on the diaphram. Vacuum on the diaphram at idle pulls the diaphram and rod back against the spring, lowering the fuel supply.
..The higher venturi hose connection is to equalize pressure on the diaphram in accordance with the presures in the intake above the butterfly.........
Dude can you post a pic of the other part of this diagram .. I wanna see how the HAC conect ( and control ) with the fuel " rod " inside the IP ..
Dude can you post a pic of the other part of this diagram .. I wanna see how the HAC conect ( and control ) with the fuel " rod " inside the IP ..
It doesn't do it inside. It does it outside. The handle that you move to stop the engine is blocked from going the other way by the hac. It simply allows less max fuel at higher altitudes.
It doesn't do it inside. It does it outside. The handle that you move to stop the engine is blocked from going the other way by the hac. It simply allows less max fuel at higher altitudes.
Here's the lower half of that line drawing but it doesn't really help to show how it is connected:
View attachment 238327