Ok, so less than a year ago I replaced my vacuum pump diaphram after it tore and was puking up oil into the intake. After the repair, all was well and I thought nothing more of it, but just recently it seems it tore again. I have the same symptoms (no vac/brake booster/shutoff, and oil puking out the top tube soaking my air filter. So, I am going to order another diaphram and replace it.

My question is this: What would cause it to fail in under a year? I followed this thread:Vacuum pump diaphragm replacement pix
I do believe I got the rounded washers in correctly, I didn't tighten the center bolt very hard, and I used a little locktite on it. So what causes the failure?

I do have a somewhat leaky vacuum system (My brake booster leaks pretty good, I believe). Does this have an adverse affect on the lifespan of the diaphram?

Please, if you have any insight let me know. It is a pain job, and I am afraid it will run me out of oil without my knowledge. Everything is soaked in oil again

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'79 240D 4 speed manual 105k miles