Hey Everyone,
Looking at an '85 F150 for my wife to drive for the winter. The heater core in her car doesn't work and this truck is actually cheaper than having a new one put in.
It's a 300, so it's right up my alley, but I've never messed with the feedback carb setup. We have to pass emissions here in Boise, so that's a consideration. The only thing it needs is a new distributor, so I'm thinking I'd rather just put on the 1bbl from my Bronco and revert it to a Duraspark II setup. However, I'm not sure how much of the emissions stuff ties in with the Feedback stuff. Anyone know?

Any insight would be great. Thanks!

 

I had an '85 E150 with the feedback carb. It was all oem, passed smog, and ran good. Held a high idle sometimes, but I never tried to fix that.

You will find a row of solenoid looking gizmos with vacuum lines going here and there. (Certainly I could come up with the proper terms, but...)

The problem with these is the vacuum lines. Brain-surgeon candidates slash them in an effort to "take all the smog crap off". They break easily, as they are plastic. Tracking them down can be a real chore.

It needs a distributor? As in it's worn out, or there is none? If it won't run, you are buying a sizable question mark.

How does it look otherwise? Loose ends? Plugged lines?

An '85 has the TFI ignition. Some (like mine) had the module on the distributor.

What are your smog rules like? Pass at the pipe, or are they going to check for all OEM equipment?

As for the conversion back, afaik, the computer does control timing.

 

Thanks for the response.

I'm going to look at the truck tonight and haven't seen it in person. The truck is in great shape. He said it had some rust, but I can't see it in any of the pictures. It looks very straight and clean. Clean interior, etc. $300 because he lost interest.

As for the distributor, he said his friend tried to recurve it and could never get it to run again. He bought it from him thinking he could do it, and eventually got it almost running, and then gave up. Before that, it ran fine. I've messed with distributors well enough on mine that I imagine I can either get that one working, or just spend the $50 for a new distributor.

I know all too well about the nest of color coded vacuum lines that plague the underhood of a 300. I replaced all of mine. Fun stuff. It sure ran better when I was done with it though. I imagine I'd be giving it that treatment within no time.

I know it's a question mark without it running, but for the price I figure it may be worth a shot. If not, I could almost part it out for more money than I pay.


Smog here is pass at the pipe. My Bronco passed with a 1bbl and cat. The smog pump and EGR were non-existent.


I know the computer controls the timing, which is why I was planning on replacing the distributor and ignition module with a Duraspark II counterpart. I just didn't know if any of the AIR injection stuff in the head (which mine doesn't have) for the emissions tie in with the TFI setup anywhere.

 

The stuff you said about recurving the distributor doesn’t make sense as the EEC IV dissy is computer controlled and does not have any springs. The recurving thing is just for the mechanical advance part of a distributor in a vacuum advance style distributor.


I was in Boise a few weeks ago and saw an emissions testing trailer at a gas station, a mid 60 Ford mustang was in line for the test, the test guy opened the hood for a look. Here in Spokane WA, they don’t look under the hood. I will be taking my last emission test on my 1986 F150 next month as they stop testing at the 25 year point and only test every 2 years. I have always been stressed out about the emission testing here as the truck has had lots of trouble passing the tests with the feedback carb and EEC IV in the past. The PO had a few failed tests but I have always made it by a hair, a very thin hair.

The air pump has 2 vacuum controlled directional or maybe just on/off valves which are computer controlled by solenoids on the back of the valve cover. One direction is down to the pipe, in-between the cats. The other is up near the base of the carb, the air pipe is shown in the photo just to the right of the EGR and used to keep it from backfiring while coasting down a long hill; it dumps in more air in the intake manifold to make it lean. I just hooked a vacuum source to the one that dumps it in the pipe near the cat as I thought that would help me pass the emission test the best. With a vacuum source the valve is open, no vacuum it is closed. My EGR had a blocked plate install just before my last test 2 years ago. After I passed the test I took the belt off the AIR pump but will be reinstalling it again for next month test.

Here is a photo of the Carb I am current running; it is a feedback Carb I bought of ebay before I knew what I should have bought. I replaced it because the old carb had a steady stream of gas coming out the small brass pipe which I believe was the accelerator pump output. Your carb will look like this as I don’t think they used throttle plate sensors in 85. If it has a throttle plate sensor (like my 86 did) it will be on the front side of the throttle shaft. Some Carbs also had fast idle solenoids that were computer controlled also, so it wouldn’t die when you turned on the AC while sitting at a stop light.






I guess what I am trying to say is if the Bronco passed emissions then this should pass with the feedback Carb and a DS2 dissy. The computer controlled feedback solenoid that is bolted to the side of the carb will not really make a difference in the big picture if it is not hooked up as far as emissions go. I still get 15-16 MPG with this carb and a C6. If you are just going to use it around town with very little over 60 MPH freeway driving I wouldn’t even mess with changing the carb as it wouldn’t be cost effective in the big picture… unless the gas mileage sucks.

Jim

 

Lol, PROBABLY why they couldn't get it running again, if they screwed with it.

Nah, they don't look. The hood is up simply to hook a sensor to the #1 spark plug wire. This goes to a computer so they can watch your RPMs since one test is at idle, and the other is at ~2500. The guy who tested mine would have blatantly seen that my smog pump didn't have a belt on it and wasn't turning, if he had cared to look.

Thanks for all of the information. That's good stuff to know. Unfortunately, the truck sold a half hour before I was to go look at it. I guess that's how things go. But since we're in the market, I'm pretty sure we'll run along another one so it's again really good info.

 

I have no problems with my 86, it just passed emissions, the tester said it was the cleanest truck through there all month. only problem I have had was a fast idle, and I took a wrench, and backed off the electric plunger, then adjusted the idle with the screws on the side like the old carbs. if you don't pass emissions, put 1 gallon of denatured alcohol in your tank, right before you go to emissions. it will pass with flying colors that way. my 82 did, and so did my mustang. both were a pia to go through the test, every time until the guy at the test station pulled me aside, and gave me that little tip. it works.