Which MC2150 is better?

[DaveMueller]

I managed to find 2 MC2150s at the u-pull-it lots this week. The first one is clean but must have been full of water, the throttle plates are rusted shut. The second was dirty but has nice throttle plates. No ID tags on either, but there are numbers stamped on the choke pulloff, E2TE-BA and EITE-AA.

The first has a few differences (from an 85 Bronco II) - a vacuum cylinder on the front between the fuel inlet and accelerator pump, some type of electrical device on the back, and another on the throttle shaft (throttle position sensor?). It also has an additional passage on the top of the body, on the other half from the choke plates.

Any ideas what they are, which carb is "better", or should I make a hybrid from the two?

 

[DaveMueller]

http://www.carburetion.com/diags/2150diag.jpg

#16 Feedback control assembly
#51 Pump relief valve assembly
#60 TPS as I suspected.

I'm guessing my Jeep doesn't care about the TPS and probably not about the feedback control ;-)

What do I do with the pump relief valve?

 

[elwood blues]

The one on the left of both pictures, that you have red circles around is an altitude compensator version of the MC2150. From everything I've read, they're were not a ton of those made, they were mainly for use our west in the Rockies, as the barometric pressure goes down it causes that thing on the back to open, adding more air to the mixture thinning out the air to fuel mixture so that the engine isn't flooded due to the thinner air, and inversely closes as the altitude decreases.

I don't know if it's anything you'd ever need in PA, the changes in altitude aren't that great. However, it is in much better shape than the other one.
I know you can't remove all of that stuff from the carb, it won't work right without it.

You could try to sending either one off to be remanufactured, there are a few places out there;

Carburetor Rebuild & Return Service - United Remanufacturing Co.

Carburetors ? Buy Wholesale Direct - Get Free Shipping and a Lifetime Warranty!

http://www.allamericancarburetor.com

https://www.carb-x.com

 

[DaveMueller]

Thanks. Yes it's 99% cleaner but the vehicle didn't have a hood so the throttle body filled up with water and rusted the throttle assembly. Buying another was cheaper than ordering new butterfly valves, plus now I have spare parts.

I'm happy with the altitude compensator, my daily commute changes from 2500 to 800'. Might not make a huge difference but I doubt it hurts. Took some head scratching to figure out why water boils at 206 degrees at home!

I bought some naval jelly to soak the bottom end, if that doesn't work, I'll try molasses which I've seen recommended a few places.

Merry Christmas
Dave

 

[Lumpy Grits]

Ketchup, does a better cleaning job.
LG

 

[elwood blues]

Merry Christmas to you too, take pics and keep us updated, I'm interested in hearing how the altitude compensator works for you

 

[Peanut Butter]

Thanks. Yes it's 99% cleaner but the vehicle didn't have a hood so the throttle body filled up with water and rusted the throttle assembly. Buying another was cheaper than ordering new butterfly valves, plus now I have spare parts.

I'm happy with the altitude compensator, my daily commute changes from 2500 to 800'. Might not make a huge difference but I doubt it hurts. Took some head scratching to figure out why water boils at 206 degrees at home!

I bought some naval jelly to soak the bottom end, if that doesn't work, I'll try molasses which I've seen recommended a few places.

Merry Christmas
Dave

There is a relative new product on the market that you can buy at Wal Mart and most auto parts stores called Evpo-Rust. It is non caustic and works very well. Might try it. I used it on a completely rusted bolt for a gun. It now works perfectly.

 

[Scorzany]

You could try to sending either one off to be remanufactured, there are a few places out there;

Carburetor Rebuild & Return Service - United Remanufacturing Co.

Carburetors ? Buy Wholesale Direct - Get Free Shipping and a Lifetime Warranty!

http://www.allamericancarburetor.com

https://www.carb-x.com

Does anyone know which one of these are the best at rebuilding? I want to send mine off for the works! Price is not much of an object because I want a top notch job done on it.

 

[DaveMueller]

I started with lots of naval jelly on the throttle assembly to remove the major rust.

I bought a jug of Permatex rust remover, probably the same stuff as Evap-o-Rust. I put the carb in a vacuum seal bag (don't tell the wife!) with about a quart of remover, then submerged the whole thing in a bucket of hot water. Not much happened but then the remover turned from clear green to murky green and the bag swelled up. I seem to remember the process creates some nasty gas as a by product, so be careful. Definitely wear gloves and safety glasses. Probably close to an hour total.

Rinse well in hot water, then rinse again in hot water and baking soda to neutralize the acid cleaner.

The carb cleaned up really nice, but now I have a black greasy film all over it. Maybe time to try dish soap.

The advantage of the Evap-o-rust type products is they are very thin and can get into small cracks.

I did get the throttle loose, and one of the plates out, but the screw heads on the other plate broke off. I was surprised that the two carbs have different size throttle plates, I was hoping to swap them.

 

[DaveMueller]

A little more research shows the one on the left to be a "feedback" type carb (the Ford guys are calling it a 2150A), the computer controls the valve on the rear to fine tune a/f ratio. I found a link that shows how to make a plug with 2 screws to manually adjust the ratio.

I think I'll switch focus to the one on the right for a while.

 

[elwood blues]

A little more research shows the one on the left to be a "feedback" type carb (the Ford guys are calling it a 2150A), the computer controls the valve on the rear to fine tune a/f ratio. I found a link that shows how to make a plug with 2 screws to manually adjust the ratio.

I think I'll switch focus to the one on the right for a while.

Would you share the link to where you found this info? I'm always try to learn more about the 2100 series carb, thanks

 

[DaveMueller]

2.8 Duraspark/Metering Valve - The Ranger Station Forums

I never thought of looking at Ford message boards!

 

[Peanut Butter]

The carb cleaned up really nice, but now I have a black greasy film all over it. Maybe time to try dish soap.

Try vinegar. It'll take the bluing right off a gun.

 

[DHugg]

Re: 4H 2H N 2L etc

Dave, my 1980 CJ7 has an auto, TF999, mated to the D300. It has the same shifter pattern for the D300 that you show, and all work as placarded.

You might try OSPHO by The Skybrite Company of Cleveland, OH on your rusted carb parts. I have used it for decades, and that is descriptive of how long it stops rust from reforming. I have a steel trap hanging in my garage that was treated in about 1968 (Gulf Coast humidity and hurricane atmosphere) and still is rust-free.

I got the stuff at one of the major paint distributors. One quart bottle will last a long time.

 

[Hedgehog]

Those screws on the throttle plates broke off exactly the way they were designed to do. The screw s are put in place then lightly but effectively peened in place. You don't want those screws coming off and ending up in your engine. To remove the screws you need to very carefully grind and drill the back side to remove the peened threads. Yes, occasionally you can remove the screws, but don't count on it.

 

[DaveMueller]

Those screws on the throttle plates broke off exactly the way they were designed to do. The screw s are put in place then lightly but effectively peened in place. You don't want those screws coming off and ending up in your engine. To remove the screws you need to very carefully grind and drill the back side to remove the peened threads. Yes, occasionally you can remove the screws, but don't count on it.

Nuts (figuratively speaking). The screws on donor carb #2 came right out. I never thought they would be peened over. I have seen some recommendations for thread locker when you put them back in. I'll try to dremel the back sides off, there may be enough slot left to get them out.

 

[DaveMueller]

Re: 4H 2H N 2L etc

You might try OSPHO

I've heard of Ospho when researching something else. Rumor had it that some of the home improvement stores carried it. I bought a jug of Rustoleum Rust Remover and it did a pretty good job, especially on the light surface rust. I have more parts to do, I'll try to remember before/after photos.