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Vacuum pump or reg or what?


HRM

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My vac pump died about a month ago and a week later I took it for Annual. Sure enough, pump disintegrated. The pic shows the flight (actually, my FR) where the pump failed, then the flight home from Annual with the new pump purring perfectly along at 5.5 or so, and then the flight last week where I kept getting vac warnings on my MVP-50 (4.5-5.5).

Is this how a regulator goes south? I have not pulled the cowling and looked at anything yet. I have the full-monty Brittain system (Step, PC and 3-axis A/P).

I also have the big filter that protects the system from a disintegrated pump.

Vacuum Issue.jpg

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On 10/5/2016 at 9:10 AM, BDPetersen said:

Is the filter downstream of the pump? Usually they are on the intake end of the systems. The theory is that after a pump failure, the spinning down gyros inhale debris backwards into system. But maybe you have a different system.

Frankly, I don't know. I mean I have seen the filter and can probably find the pump and regulator.

I am going down to the hangar tomorrow and pull the cowling (just give me a bullet) and take a look.

I just wondered if anyone had any thoughts based on the data, like "Yup, the reg is blown" or something.

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Its possible the reg is out, but I have yet see one failed. I would start with checking the condition of every inch of hose, may be dry rotted, or rubbed thru somewhere. Another common issue I see is the plastic fittings that go into the gyros get tightened too much or get bent, both causing cracks. I know nothing about the brit servo system, but I imagine there is plenty of line to look at. Do you have other indications that the vacuum is actually fluctuating? factory vac gauge needle bouncing, gyro flags, brit system acting weird (again, i know nothing of the Brit system)? I have yet to install the vac sensor for a JPI/ EI system. where is its location to the pump, could it have been damaged or clogged when the old vac pump exploded? 

Those are my ideas, good luck.

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I am now thinking it is the Aerotech filter. I have a new one on order. It has been in the plane for 20 years. Mine is on the left and a new one on the right. I noticed that the pleats in mine are bowed and it looks like it has been sucked in. 20 years, time for a new one anyway.

VacFilters.jpg

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