Motorcraft 2150 Carb Body Plumbing

[Brypur]

Do we have any carb experts on here that may know how the 2150 is plumbed internally?

I have pulled the feedback solenoid off the back of mine and replaced it with a block off plate. This solved a idle mixture problem I was having due to a defective feedback solenoid but messed up the main circuits. I am thinking that it meters the amount of air into the emulsion tubes to adjust the mixture and by blocking it off I have killed my mixture as anything outside of an off idle condition it is just running way too rich with no power.

The carb body has 2 small ports and one large one where the feedback solenoid mounts. Anyone know where those ports go to and what they do? I am considering either putting a bypass slot in my block off plate to connect them or trying to find an aneroid that would fit and see if that might help.

BTW, I did try to rejet and dropped from the stock 50's to 48's and that helped a little but judging from its impact I would have to drop at least 8-10 jet sizes to get it close and aside from those jets not being available I would think the engine would then be starving for fuel. The carburator also has just been rebuilt and all seemed to be in order mechanically.

Ideas? Thoughts?

Thanks,
Bryan
1985 Ranger, stock 2.8l V6, 5 spd, desmogged

 

[RobbieD]

Go to this post, read it, and follow the link that's in the post.

http://www.therangerstation.com/forums/showthread.php?t=981&highlight=martin%27s+metering+block

I recently Durasparked my '84 2.8L, kept the 2150A, and made one of these metering blocks for it. My truck is running better than it ever has.

My understanding on the 2150 is that the feedback solenoid shouldn't screw up the main circuits as drastically as you're experiencing. But, I'm not a carb expert by no means; however, there's several sharp 2.8 guys on here, and hopefully you'll get some better input on getting yours straightened out.

Do you still have the factory setup, except for the feedback solenoid? Or, did you also Duraspark it?

 

[Brypur]

Perfect!

That is exactly what I needed to know and a great fix to my problem.

No I have not durasparked it yet. Basically I am just dealing with problems as they arise and to date ignition has been behaving itself. I knew my carburation was off so thus the rebuild and troubleshooting of issues.

Bryan

 

[martin]

You might want to leave the metering valve plugged into the harness if you are still running with the computer. Don't need it going into limp mode or you will lose the advance on the timing. I'm not saying it will, I'm saying it might.

 

[Totalled]

Duraspark, kick that POS to the curb and replace it with a older 2100 or a 2300 holley. Trust me.

 

[Brypur]

You might want to leave the metering valve plugged into the harness if you are still running with the computer. Don't need it going into limp mode or you will lose the advance on the timing. I'm not saying it will, I'm saying it might.

I may be there now. Carb is so messed up it is not even worth looking at timing issues yet. The air pump was removed by the previous owner, I just removed the EGR valve and I am willing to bet the O2 sensor and catalytic are shot. Given all that I am not sure what the computer is thinking right now but the feedback solenoid was messing with the idle, had no power and dripping fuel when I removed it so not sure it is much good to put back on. My goal was to get back control over the carb so I could tune it for the current conditions.

Duraspark, kick that POS to the curb and replace it with a older 2100 or a 2300 holley. Trust me.

I have considered an older non-feedback 2150 or 2100 but decided to see if I could get this one running right first. Seemed to be the cheapest alternative at this point. If I run into unresolvable issues then I will drop back and punt with an older non-feedback carb and duraspark if need be. Current budget dictates that I spend no additional money unless required.

In fact too many problems will push me into the CFI conversion as Oregon has mandated 10% ethenol fuels for all street vehicles and I feel FI holds up much better with ethenol then carbs. I have one station yet that will sell me non-ethenol but their distributor has threatened to shut them down just because they still have a hose with non-ethenol in it. It is legal for boats, 2 cycles and '55 and older cars so there is still demand for it.

Bryan

 

[martin]

I ran mine with a metering block and the computer controlling the timing for a few years with no problems. I did the duraspark conversion after an incident on a trail damaged the harness and took out the computer. The truck still starts first time and runs like a charm with the 2150 and metering block, duraspark distributor and gm hei module. One thing you might check is the power valve , they like to leak and will cause an over rich condition, I seem to recall it has an external vacuum hose controlling it which might also be worth taking a look at.

 

[Brypur]

I replaced the power valve when I rebuilt it but not outside the realm of possibilities that I got a bad one. As for the vacuum hose on the front of the carb, that was replaced about a year ago due to a vacuum leak and was rechecked when the unit was rebuilt.

Right now I am running with a block off plate where the feedback solenoid used to be thus I have basically plugged my air bleeds. Truck idles fine but runs like crap for obvious reasons. No time today but probably tomorrow will make the metering plate and get it back into some resemblance of normal operation and be able to tell if I have a power valve problem or not. My guess is once tuned all will be fine again.

Thanks for the help including the design of the metering plate!
Bryan

 

[dangerranger83]

I'll tell you now putting the CFI/TBI unit on my 2.8 was the best decision I've made. Runs great starts right up but I dont know the fuel milage. I recommend anybody with a 2.8 to do it. For more on that check out my build thread.

 

[RobbieD]

The Duraspark conversion is definitely the way to go. With careful shopping you can do it very reasonably, too. I did mine a few weeks ago, and spent in total around $150, which included the distributor, adapter, cap, wires, plugs, coil, resistor, new valve stem seals, and valve cover gaskets. The 2150A can be used successfully, as I did, or there's the other options as mentioned. Mine runs great, and the tank of gas that I just used up gave me 18.4 MPG (mainly because I drive the truck real easy).

Keep working with what you have, though. I think you can tweak it to do a lot better, but do consider doing the Duraspark when you can. Good luck with it.

 

[dangerranger83]

My TBI set-up costed $75 and depends on what mean of how you want to deliver fuel, such as getting the 2.9 or 2.3 (just needs to be 44psi) tank which would have costed me $50 bucks but my truck was already FI so the fuel delivery was already there but an inline fuel pump shouldn't cost to much.

Whatever rought you take doesn't matter as long as you get your truck running right.