View Full Version : Motorcraft 2150 rebuild - aneroid gasket issues

03-11-2003, 01:02 PM
This is the third 2100 series carb that I have rebuild, but the first one with altitude compensation aneroid as far as I can remember.

The gaskets that I removed from aneroid assembly were a lot thicker than the gaskets that were supplied with the Sorenson rebuild kit.

Is there a way to make a tight seal with these thinner gaskets or do I need to buy some bulk automotive gasket material and cut some matching gaskets to thicken it up?

What is the deal with this aneroid thing anyway? Is there a way to bypass it? The valve in there was sooty. I wiped it off and reinstalled it, but the spring in there doesn't push the valve back. Is it supposed to reseat the valve?

If anyone can explain a way around the aneroid or a way to make sure it is installed properly on my carb, I sure would appreciate it!

Thanks smile.gif

Edit: Fixed my spelling of aneroid smile.gif

[ March 11, 2003, 08:30 PM: Message edited by: BostonWrangler ]

Don S
03-11-2003, 01:23 PM
... I would make the thicker gasket. You don't want to become a DSPO...
You could make a block-off plate at the top where it should have a little choke of it's own.
... HAC High Altitude Compensator system or AAC = Aneroid Altitude Compensator – were available on the Motor Craft MC-2150 and the MC-4350 carburetors. Motor Craft 2V (barrel)

The HAC system should not have any effect on the idle vacuum.
All the extra air discharge is above the throttle valves. The aneroid expands and contracts with altitude.

Good luck and ;) and … CUL.. Don S..

03-11-2003, 01:29 PM
Thanks for the info Don!

Originally posted by Don S:
I would make the thicker gasket. You don't want to become a DSPO...
You could make a block-off plate at the top where it should have a little choke of it's own.I wish a block-off was that simple. The whole reason I need these gaskets thicker (to seal the aneroid properly) is because the aneroid feeds directly into the barrels of the carb. Even with the choke part blocked off, leaks in the aneroid and/or gaskets would cause fresh air to be sucked into the carb aft of the venturis all the time.

The block off plate would have to be somewhere to stop the air from being pulled in aft of the venturis where the aneroid feeds enter.

Don S
03-11-2003, 03:29 PM

... There is an atmospheric pressure inlet to the first chamber where the aneroid actually is. Then, IIRC, Only the shaft of the aneroid sticks through the area where the gasket is and my ’81 model was a tight fit and not much air could leak past the hole ie the shaft plugs the hole.

http://www.ifsja.org/tech/fuel/2150.shtml FSJ MC-2150 CARBURETOR
http://home.earthlink.net/~bubbaf250/2150carb/carb01.html MC-2150 CARBURETOR

Good Luck ;) and CUL.. Don S..

03-11-2003, 03:40 PM
OK, you're right.

I still think that the first gasket between the valve assembly and the carb body isn't thick enough. I tightened it down as much as I dared (didn't want to strip any threads) and it seemed like a decent seal, but not as good as the original.

Also, the valve shaft did not slide freely. The return spring wasn't doing it's job. I am going to clean the shaft with brake cleaner tomorrow to get the grime off of it and hope that that helps it move more freely.

There is also a little rubber grommet that holds the valve shaft in place. My rebuild kit didn't come with a new one of those. Could this rubber piece be causing it to stick?

Thanks yet again!

03-12-2003, 06:25 AM
Put a streight edge across the "flat" mounting face and I bet yours
is warped, at least every one I have had has been, it is a real ***** to
mill it flat again with out taking off the locating lugs but that is what
I ended up doing.

Mike D.

03-12-2003, 07:51 AM
Yep it was warped. I ended up stripping the threads out of one of the mounting holes.

I made 2 extra gaskets and stacked them with the one provided in the rebuild kit. It seems to work. I am going to get a bolt and nut and make sure that the stripped side is tight enough also.

Darek- I stripped one of the mounting points on the aneroid thinger.

I did get everything installed. I made sure that the idle screws were backed out 1.5 turns, installed the carb, hooked up all the hoses and tried cranking the thing over.

After a few cranks to get the bowl full of fuel and a few squirts of starting fluid, she fired up. A lot of white smoke from the tailpipe but the engine revved up nicely. I think we didn't tighten the exhaust manifold-to-pipe connection tight enough cuz there was a pretty nice white plume coming out of that area on the driver side. The plume went away once the engine was running for a few minutes.

And once it was warmed up, I took it for a spin and it idles so nicely now! I don't have an exact number for the idle speed cuz I don't have a tach, but it is nice and low and sounds like, "rum rum rum rum rum rum rum rum." So steady and soft. I love it!

Now I need to patch the leak in the metal fuel return line along the frame above the front axle!!!

Oh yeah, and there is a ticking noise coming from the clutch when I press the pedal in. When the clutch is engaged, there is no ticking. The ticking sound increases with engine speed. It seems to change intensity from time to time. I never heard this noise before. Might it be related to the new starter that I installed?