Hey! I was wonder if you people can help me out Not getting much from the first gen community on this topic.

My Oil meter pump tubes are draining when I park my car for about a day or so. Is this normal or is my OMP failing? There are no leaks and I tightened up the spring clamps that go around the rubber tubes that make the seal.
Can anyone confirm or shed some light on this for me?! That'd be great. Here are two pics to show the oil draining back.

 

Couldn't say, but I always run a bit of premix alongside my OMP. I figure that if either system is marginal (injectors turning off during engine braking... omp lines going dry...) then the other can fill in.

 

I am sure that they operate under vacuum too,so If they drain a bit it no big deal.
The pump will eventually fill them back up to snuff and the engine's vacuum will take over and suck oil when needed.
Also Colin has a good point of "security Premixing".

 

When I still had "clear" stock OMP lines, I always thought they looked mostly empty...there would be air gaps between blobs of oil and I was concerned enough to look into the various OMP bypass options.
BUT...my ECU was not throwing codes (it's a S5) and the engine ran quite well to almost 300k miles, all the time the OMP lines looked sketchy.
Disassembly showed the housings and irons looking really nice, in fact, they're being reused on a new rebuild. So apparently, the system was doing its job just fine.
Absent any other symptoms, I wouldn't worry about it.

 

Thanks all for the inputs. The pump eventually does refill the two lines back up, pumps well and stays full while running.
I run about 8oz of premix as well at each fill up of fuel.

 

I was just thinking about the same thing.

I dont't drive mine very often, so every time I start it up, those oil lines are emptey.

I've also heard that the omp starts working at 60 degree C oil temp, so its not really doing anything for a while.

 

I don't believe that's true, I don't see any way the OMP would even know what the oil temp is and the ECU certainly doesn't either.

 

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The Haynes workshop manual (1979 thru 1985 models) says that 2.0 to 2.5 cc of oil should be discharged when running the motor for 6 minutes at 2000 rpm. Has any of you ever done a measurement on the amount of oil discharged from the metering oil pump? 2.5 cc in 6 minutes seems like such a small amount.

 

On my 84 FB it is all manually operated. The FC's omp works identical as the FB's other than the fact that they have four output tubes as opposed to two on the FB. Flow is directly controlled by the throttle position. I can manually increase flow by pressing up on the OMP lever with my finger without affecting throttle speed (at idle), hense increasing oil flow to the carbs.
Here's a pic of my OMP being cleaned up

 

Good point.

Altough I can remember that when I just had the car, I paniced a bit because I didn't see the oil moving inside the oil lines. I believe someone gave me that answer when I asked about it.

But that could be 6 years ago..