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MC 2150 empty bowl

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BeagleRock

MC 2150 empty bowl

Remanufactured Motorcraft 2150 has very little fuel in bowl after sitting overnight. I recently put an aluminum spacer on it as the original synthetic plastic one was slightly warped. I also put one of the carbon fiber 1/4" gaskets on the bottom and a 1/32" on top of the spacer, well that made the carb sit up too high and made the throttle cable fit on the shaft at an angle which created a binding sensation meaning once you had it passed the initial travel it was OK.
So I ordered 2 of the 1/32" flange gaskets to drop the carb down to where it would be even with the cable as to create a smooth throttle pedal action. Well what I discovered was very gas soaked gaskets upon removal of the carb and spacer. Also the fuel bowl didn't have much in it as I almost had to turn it 90 degrees towards me to get some gas to run out of the inlet opening.
This is making me think that whatever the reason is for low fuel level is also why I have a tough time getting it started after sitting for a day or more. I don't see any damp spots around the PV. Anyway that's my story for today 🙁 83 351W

Beaglerock/83f150 351W C6 Transmission 2 wheel drive.

Gary Lewis

Re: MC 2150 empty bowl

Administrator

If the power valve is blown or its gasket is leaking the leak will be to the inside of the carb, and you'll get essentially the results you are seeing - wet gaskets and a dry bowl. Plus hard starting.

Or, if yours has the remote PV sensing via a vacuum hose, it'll run into the intake manifold via the hose.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

BeagleRock

Re: MC 2150 empty bowl

Gary you never have good news for me
😉

Beaglerock/83f150 351W C6 Transmission 2 wheel drive.

Gary Lewis

Re: MC 2150 empty bowl

Administrator

And that's my fault?

If yours is the remote-sensing PV you can remove the hose from either the carb or the manifold after turning the engine off and see if the PV leaks.

Hmmm, maybe that's why they went with the remote PV feed. They'd had so many of them blown they needed an easy way to test?

Gary, AKA "Gary fellow": Profile

1986F150Six

Re: MC 2150 empty bowl

Administrator

Gary Lewis wrote

Hmmm, maybe that's why they went with the remote PV feed. They'd had so many of them blown they needed an easy way to test?

Had your afternoon coffee, yet?

Gary Lewis

Re: MC 2150 empty bowl

Administrator

Yes. Does it show?

Gary, AKA "Gary fellow": Profile

1986F150Six

Re: MC 2150 empty bowl

Administrator

No, I was thinking you needed some!

BeagleRock

Re: MC 2150 empty bowl

In reply to this post by Gary Lewis

No I was kidding hence the 😉

Beaglerock/83f150 351W C6 Transmission 2 wheel drive.

BeagleRock

Re: MC 2150 empty bowl

In reply to this post by 1986F150Six

Need something!!! 😀

Beaglerock/83f150 351W C6 Transmission 2 wheel drive.

BeagleRock

Re: MC 2150 empty bowl

In reply to this post by Gary Lewis

Mercy sakes alive it's HOT down here in the Gee... fortunately I had a spare PV 6.5 whatever that means. No remote vacuum on this one so I'll change it and check back in shortly. 105 heat index yikes!

Beaglerock/83f150 351W C6 Transmission 2 wheel drive.

Gary Lewis

Re: MC 2150 empty bowl

Administrator

79 degrees here in 'took. And a t-storm.

6.5 is the point in inches of vacuum where the power valve opens. Above 6.5" it is closed, but below that it'll be enriching the mix for power.

Gary, AKA "Gary fellow": Profile

JMUBullnose

Re: MC 2150 empty bowl

In reply to this post by BeagleRock

Interesting - I have potentially blown PV on my trouble shooting list as well for the 2150.

I worked on the truck over the weekend and haven't driven it since Sunday. Last two days as it sat in the driveway I would occasionally get whiffs of fuel when walking by it while working in garage or in yard. No puddles under the PV that I could spot but that could also help explain some of my hard start issues as well.

1984 F-150, 302 CID (5.0 L) Windsor V8, 2 BBL carb, power windows added, remote entry added. AC. Automatic Transmission.

Gary Lewis

Re: MC 2150 empty bowl

Administrator

PV's, and fabric accelerator pumps, are the achilles heel of Holley or Holley-type carbs, and the 2150 is one of those. The original design was flawed as it allowed manifold vacuum or pressure to get directly to the power valve such that a backfire through the carb would frequently blow the PV. A fix for that error was finally applied to new Holley carbs as of 1992 and is available for retrofit to the bulk of carbs that don't have it. But I don't think it was ever applied to the 2100 or 2150 as they were out of production by '92.

Sitting at the bottom of the bowl, as the PV does, when the fabric is blown two things happen. First, when the engine is running the vacuum usually can't overcome the spring and the valve stays open. At first blush that would seem like it just causes the mix to be rich by however much fuel can flow through the PV's orifice(s).

But, the second thing is that there is now a direct path from the bowl of the carb, through the power valve & its diaphram, and into the intake. So, when the engine is running gas is being pulled directly into the intake. And when the engine is off gas runs out of the bowl into the intake and the bowl is dry when you try to re-start the engine.

Gary, AKA "Gary fellow": Profile

BeagleRock

Re: MC 2150 empty bowl

Very in depth explanation, I appreciate it and need all the help I can get. Heading to my old Hometown of Webbers Falls tomorrow to work on a lawnmower, something I KNOW about lol. I hope the Bluebird of Happiness gets me there and back safely!

Beaglerock/83f150 351W C6 Transmission 2 wheel drive.

BeagleRock

Re: MC 2150 empty bowl

In reply to this post by JMUBullnose

Join the dry bowl syndrome club 😉

Beaglerock/83f150 351W C6 Transmission 2 wheel drive.

Gary Lewis

Re: MC 2150 empty bowl

Administrator

Good luck!

Gary, AKA "Gary fellow": Profile