Morning all,
New here , definite rookie status on much of the stuff on my new olds. love this community!

The flap /door on my OAI set up is stuck in the open position.

Can I assume that the small vacuum unit that causes it to drop open when punched is worn/ no good? Any other possibilities?. If so what's the best place to shop for small parts like that?

Thanks

 

The flapper is normally open. The actuator pulls it closed under high engine vacuum conditions (i.e. idle and part throttle). Assuming it moves freely, either the actuator or hoses leak or the hose is not connected properly.

 

Ahhhhhh. See, I told you I had serious rookie status here! Lol . I actually believed it worked the other way. Thank you for straightening that out?

 

You're not that much of a rookie, you did refer to it as the OAI flap, and not a "Ram Air" part.

 

Lol. Thanks 70 w-32.
As I said in a previous introductory post a few days ago I've been reading this blog for a long time But I have not owned an Oldsmobile for nearly 30 years. I've got quite a bit to learn and re-learn. Finally was able to get to a place where I could get myself a toy which I just received late last night and drove for the first time today. A person in my position really appreciates this website and the true Olds fan community atmosphere.

 

I bought mine from Supercars Unlimited but I've heard that the owner has some medical issues and is not fulfilling orders. You can also get one from the Parts Place. Here is the listing on their website.

 

Sorry to beat this topic up but.... I need some more education. If the above quote is true then I clearly misunderstand how this system works.

To the layman you woukd think this unit drops open when you get on the throttle hard, letting more air in there to mix with more fuel. Is this wrong?

When should this flapper be open, and when closed?
According to the above quote it's normally open but while sitting at idle and at "part throttle" should be vacuum pulled closed? Mine does not close at idle or part throttle ? (Maybe my vacuum motor is shot? Any way to test that unit b4 dropping $50 for a new one?) All vacuum lines appear to be hooked up.

it opens when? When you get beyond "part throttle"? Could you watch this happen with the hood open simply by operating the throttle at the carb?
Thanks guys.


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Engine turned off = flapper fully open
Engine running at idle = flapper closed
Engine running at various speeds = flapper opening /closing proportionally to vacuum loss/gain.
Engine running at wide open throttle = flapper fully open

Yes, you can see the flapper operate while manually moving the carb linkage with the hood open. (It's actually quite fun to do)

 

Thank you. Where would I start to troubleshoot if not closed at idle?

 

I'm not a mechanic but this is how I fixed my non-working flapper.

Step 1-Pull the vacuum line off and start the engine. Put your thumb over the end of the hose and see if it has suction. Open the throttle and see if the suction drops off. If that works move on to step 2. If it doesn't work, check to see if the hose is connected to a manifold vacuum port.
Step-2-Remove flapper/actuator. Check flapper for free range of movement. If that checks out move on to step 3.
Step-3-Order new actuator and throw old one in the trash. (unless you want to try and refurbish it.)
Step-4-Install new actuator, hook up vacuum line and start engine. Flapper should work as advertised.
Step-5-Cruise around and stomp the long skinny pedal. Enjoy the sound!

Here's a video of the flapper in action. It shows how it functions around the 1-minute mark in the video.

 

Rick beat me to the answer, but here's my version anyway (basically same as Rick's).

1. It's not getting vacuum. Meaning the vacuum hose is leaky or blocked or the source does not have vacuum.
2. The vacuum diaphragm is leaking.

Check with the engine at idle, remove the hose from the vacuum motor and feel with your fingertip if vacuum is present. If no vacuum, disconnect the hose from source and use the fingertip test at the source.

If vacuum is present at the hose, buy a new vacuum motor. Otherwise figure out why the hose/source is not giving vacuum.

 

Gentlemen...ty both. I'm on it!
Great car Rick. Love the Azure blue!

 

You're welcome.

I love that color too! Wish it was mine! Here's my ride

 

Sweetness!

 

I've got vacuum!!
Looks like I'm ordering a new piece. Any 'best places to get this" ideas out there?

 

This happened to me many yrs ago. The rubber vac line was touching the intake manifold. Over time it melted the rubber tube vac line and of course quit functioning at that point. Takeaway, make sure its not left sitting on top of the intake.

 

Now that you got the problem figure out...plug the vacuum line running to the canister so its open 100% of the time. your engine will appreciate it, especially when your sitting in traffic on hot days.

 

that looks real nice rick the darker lighting the wet road surface the gold 442 well done sir

 

Mine twitches as the idle lopes. Kind of cute.

That vacuum motor is also a Camaro part. Maybe the RS headlight doors.

 

Best place to buy one?

 

Thank You RR. Another member on here took some really nice pics of his car with the low lighting and wet pavement. I thought it looked cool so I gave it a shot. Not bad for a cell phone pic. lol

 

Go back and look at post # 6 in this thread for a couple of options to buy the part.

 

Sweet. Ty. Somehow I missed that.
Was it that gold color out of the factory?

 

The OEM vacuum motors were plated in golden cad.

 

Nice! Love that.
thank you