Vacuum pump/late shifting M1009

[milradioman]

Do you have any pics of the inside? I like to "autopsy" my old components to see how they function. I don't want to cut mine open yet, but I'm curious as to what the valves inside look like. I'm wondering if they are just stuck preventing it from holding steady vacuum. Maybe something just a small amount of oil, or wd40, could free up? This seems to be a common ailment and it would be nice to find a possible simple cheap fix/work around.

Sure, I will get some pictures posted as soon as I get home from work.
My unit was soaked in oil, indicating the seal around the diaphragm was leaking, maybe a bad valve caused oil to be drawn into it, so WD40 would not help mine.
The diaphragm can be inspected, the valves require further disassembly to get to them, I will get good pictures of the valves, and maybe try to take them apart.
I suspect since they are a diaphragm type pump and valve, they may be worn/torn from use, I am planning to find a suitable material to replace any worn out ones. I was hoping it would be and easy project, but will involve some time and creativity to rebuild.

 

[DREDnot]

Just to confrim, checked my vacuum on my M1009 just now; 20 " at idle fairly steady 25 degrees outside cold start.

Good info. Thanks!

Small temporary victory...while reassembling the head to the stem, I squirted a small amount of denatured alcohol into the vac inlet pipe and shook it around a bit. Re-installed it and fired it up. Now it would fluctuate/bounce from 12 to 20+. Vacuum reading OUT of the vacuum regulator was steady 12 at idle. Dropping with throttle as it should have. Took it for a quick blast on my test loop. Shifting nicely. Rechecked vacuum readings. started bouncing again...then would read steady. So I'm thinking I still need a new pump that holds a steady vacuum.

 

[DREDnot]

Sure, I will get some pictures posted as soon as I get home from work.
The diaphragm can be inspected, the valves require further disassembly to get to them, I will get good pictures of the valves, and maybe try to take them apart.

Looking forward to the pics. Yeah, the crimped ring needing to be ground off kept me from taking mine apart without a having a replacement.

 

[DREDnot]

You are welcome to it for a nominal fee plus the cost of shipping. Let me know.

Sending PM

 

[milradioman]

Ok, Here are the pictures of the vacuum pump cut opened and disassembled.

View attachment 702342
This is the "exploded" view, as it would be disassembled.
View attachment 702343
Shown as the unit is first opened, diaphragm and output line on left, spring and housing on right.
View attachment 702344
Housing half that bolts to the gear housing shaft and output valve , shaft side of diaphragm on right.
This should be the valve that closes as the diaphragm moves on the return cycle, most likely if the valve is not working correctly it would cause the oscillating vacuum readings we are seeing.
View attachment 702345
The housing shell and return spring, I have not looked further yet, I think the holes in the shell are air release for this side of the diaphragm.

 

[DREDnot]

Hmmm... cant see the pics

 

[milradioman]

Well, apparently I need help on how to upload the pictures, I have poked around trying to figure it out, but have not been able to yet.