Okay so I have a couple of questions...and I love the discussions that usually ensues, so please don't be afraid to ask questions about your particular situation...

I have the feedback carb - Motorcraft 2150A. I just replaced the feedback solenoid with a motorcraft part...paid way too much but it being a motorcraft is insurance enough for me...plus I dont think anyone else makes them.

1. Are the power valves on the feedback carbs prone to the same issues the holley carbs (4180, I believe) have? Needing constant replacement or expensive alternative to address the blowback issue in Holleys?

2. Since it is somewhat popular to through out the original EEC-IV system and replacing the carb...does anyone have one, or extra one, that they would be willing to sell? Always am looking for a backup carb if I need to do a quick swap to get back on the road quickly.

I'm having an issue with pinging. It pings at idle in gear. The engine pulls a constant 21" of vacumn. Compression 'feels' good, but this is subjective as I just feel the exhaust. No milky oil and no oil in the coolant. Just replaced, pretty much the entire cooling system upgrading to a 2 core radiator. Electric fans, dual. New 195 degree thermostat. (need to stay close to what the engine computer knows it should be, being in California, I'm stuck to keep most items stock...which I don't mind the EEC-IV has proven reliable for me the past 25 years or so...at least in my situation and the engine only has 234k miles.) Just can't figure out this pinging issue. Wires, new. Plugs, new. Could be ignition module? Bah...the puzzle continues.

 

It does seem like there should be good supply of removed, unwanted feedback carbs out there. I wouldn't mind having a spare too. It does look like places like LMC Truck sell them, but they cost ~ $300.

Was this feedback carb system used by Ford only on its trucks? Or did they also use it in their various Ford/Mercury car models of the same time period?

 

I don't know if LMC actually sells the feedback carb or just the regular 2150. The feedback carb is 2150A.

I believe the 2150A was used on more than one production line for Ford.

 

In your system, the computer system controls the timing. The timing is probably causing your pinging. Have you pulled any codes? Have you checked the timing? I haven't worked on a carbed EECIV, but I would assume you check the timing and pull the codes like the fuel injected EECIV.

 

I'm not sure if the Motorcraft carburetors have the blowout protection for the power valves or not, but I don't seem to hear of too many on this site blowing the power valve on a stock Ford carburetor. When a power valve blows, you will usually have an extremely rich condition and your gas mileage will go way down.

For the pinging issue, check your EGR valve. When these go bad or are removed, your engine will usually ping. After 234K miles and 26 years of service, it may very well be blown or carboned up.

I doubt the ignition module is causing a pinging condition.

If you are "stuck to keep most items stock," why did you replace the stock fan clutch with dual electric fans? It's not needed on a mostly stock or even mildly built street engine, and your engine computer may or may not agree with this "upgrade."

What type of plugs and wires did you get?

 

Yes, the EGR valve is a good place to look also. If you can get to it, try to push up on the EGR valve from underneath while the engine is idling. When you do that, the engine should try to stall out. That will tell you the passages are open.

Then with the engine fully warmed up(take it on a test drive) come back and pull the vacuum line off the EGR valve itself. Then rev the engine while feeling the end of the hose, you should feel some vacuum on it when you rev the engine.

I was also afraid in my first post, that someone has been trying to set the timing on this truck without taking the spout connector loose. I don't know if your truck has a spout connector, but if it is EECIV, I would assume it does.

 

The EGR valve and EVP has been reapaced by Motorcraft parts from the dealer. When I rebuilt the carb 5 or so years ago, I took off the EGR spacer plate and cleaned all carbon buildup.

In my search through the forums, I did find this: https://www.ford-trucks.com/forums/2...n-31-code.html

And so I will be trying this as I have always gotten the Code 31 for years.

Valid point...I decided to do this for several reasons...many years ago the fan shroud broke and just was thrown away. I broke it, took it off the truck for repair and a roommate thought it was junk and threw it away. I just replaced the radiator with a 2 core radiator (originally a 1 core setup) and since a new fan shroud was about the same price (through LMC) as a dual fan setup I got off of ebay, I decided to go electric fans and keep the few extra horses in the engine. I was looking at a new fan clutch anyways.

The plugs were just replaced with Motorcraft coppers and the wires are BWG Select wires I picked up at O'Reilly's.

I was going to do a full EGR system test this week as well as make sure all the appropriate sensors are in fact getting the 5v they are suppose to from the computer, until I came across the post above. I am in the process of applying this quick fix. Will see if that clears the code 31.

The truck does have a SPOUT connector and there are no codes about not receiving a SPOUT signal.

 

What I meant to say about the spout; I want to make sure you know the proper procedure for setting the timing. That is, taking the spout connector loose, setting the timing with a light according to the sticker on the radiator support, and then plugging the spout back in.

 

Of course. I disconnect the spout connector everythime I check timing. The timing for my truck is 10 BTDC. It is set there perfectly. I put a thin line of white-out on the 10 degree mark so it make it easy to check timing. I usually check timing at every oil change...

 

In relation to the pinging issue...

When starting up the engine...she idles great. Fast idles where she's suppose to be at. Rev the engine....no pinging. Put a load on the engine...no pinging.

Only when she gets warm, does the pinging start. Which would lead one to believe the combustion chambers are getting too hot...either by carbon buildup or by improper cooling.

Compression across the cylinders were ranging from 120-130 psi for all eight cylinders. So I went ahead and looked into the cooling system. Mind you, I replaced pretty much the entire cooling system...new heater core, new (2-row upgrade) radiator, all new hoses, new water pump, and new thermostat.

However, I put in a 195 degree stat. Looking at fordparts.com, the motorcraft equiv stat is rated at 192. Okay...let's get the cooler stat and this time...lets go ahead and get the motorcraft part and not the orielly store brand one.

Got it in today...tested them both out in boiling water. The motorcraft opens the full 1/4 inches. The old one...only opens to maybe about 1/8 inch...if that. Soooo I will see if this has an effect on the system and reduce engine temps.

The temp gauge in the dash would register a little warmer than usual...roughly at around 3/4 of the way during idle.

After reading so many posts of people not talking about some great aftermarket part...but rather mentioning they stick with motorcraft..I am now listening. Replaced the E3's that I put in the truck with Motorcraft coppers with amazing results. It might be more for the part...but you just cant deny the insurance that comes with it...

Will update on the progress.

 

I did not know anyone still voluntarily ran 2150a feedback carbs anymore.........
I thought they had all long since been tossed when the trucks were Durasparked.

I am sorry, I had 3 of em' sitting on a shelf in the garage, tossed them last summer.

 

I do enjoy my feedback carb setup... I live at sea level...literally 1 mile from the Pacific Ocean. and when I go up to 8,000 feet up in the Sierras for backpacking, the truck is as strong from home to trailhead.

3!! bah!! should have come on sooner and asked for them I suppose.

 

Scalladaballa, I wasn't aware that timing could be checked on the EEC-IV ignition system. Is it done statically with a depth gauge, or instead with the engine running using a timing light? What is the "spout connector"?

 

On EEC-IV...the computer still needs to know where the crankshaft is in relation to cylinder 1 TDC. This Spark Output signal (SPOUT) give the computer this pulse from the stator inside the distributor.

To check the timin on such vehicles, you disconnect this pulse signal. Without this signal the computer will go to its base timing, which is for me 10 degress BTDC. You check this timing using the conventional way of getting a timing light. The only thing is, you really can't deviate from the stock base timing. You just have to make sure that it runs at the timing specified on the emissions sticker up front. You might get away with going a half-degree, but the computer expects to have the engine at a certain point in its rotation when it gets this signal.

I have found a way to change the timing using the octane rod in the distributor, but have not come across other size octane rods to do this modification...or if it will do any good.

 

Pinging is not related to malfunctioning stat...but the temp needle stay right in the middle with no movement now.

She was almost pinging before the temp started climbing though...maybe I didn't notice this before... I just can't figure it out. I swear I could hear/feel her missing....it wasn't constant either...almost in waves. Hard to explain...

... Next thing is to check the EGR circuits...and solenoids... oh joy...