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85 F150 I6 need help w/ vacuum lines, choke, i.d.ing parts, etc.
I have an 85 F150 w/ a 300 I6. I have already swapped over to DSII. The carb is not a feedback. I need some help with several things.
For starters, I have already ordered a new carb that is different from the one that is on the truck. New 79 80 81 82 83 84 85 86 F150 E150 4.9 300 1BBL Carb | eBay
That is the link for the exact one. It is also a non-feedback, and it has the thermal choke. (I will get to that in a minute). Lets start with vacuum lines:
This photo shows the vacuum tree at the base of the carb. You can also see where someone plugged a hole with some epoxy putty. I'm guessing that was egr? I have a better shot of that. I need to know what the ports in the tree are for. The large vacuum line shown in the bottom left port goes into the brake booster. The other large port at the top on the body of the carb is where the PCV valve was plugged in.
This is the better shot of the plugged hole. There is another large hole open next to it, and when the truck is running, exhaust pours out of it. You can also see the PCV hose going into that port on the carb in the background.
This is located on the firewall directly behind the carb. The hose shown goes somewhere down by the transmission.
That covers my vacuum line questions, on to mystery parts:
Here you can see some sort of linkage attached to the intake manifold. It extends down to the transmission somewhere. At the end on the right of the picture, where the bolt is sticking out, there are two holes. One has the bolt stuck in it, the other is to the left of the bolt. I have a better pic of that as well.
There is the better pic. You can see the hole to the left, and the one to the right with the bolt in it.
Here's another mystery hole in the exhaust manifold below the carb. I'm thinking maybe for the choke heat?
Random unused plug in the engine compartment. It connects to the alternator.
I'm pretty sure I have a rats nest going on here, and my factory vacuum diagram is of no use to me because I have converted to non-feedback and DSII. I am also concerned about the lack of an EGR, and that the old ports for it are closed shut. Furthermore, I plan on running the thermal choke setup, and I don't even know where to begin there. I also know the PCV system is not hooked up right. Here are some shots of it and the air cleaner:
I know this is a lot to take in, but I could really use some help here. It is greatly appreciated. When the new carb comes in and I get it installed, I can take some new pics of it. Thanks in advance!
Welcome, brother. I've been working on an 81 F100 since October, and this is the place with ALL the answers. My 300 predates yours, but some elements are the same.
The mystery hole in the carb base is for the Air Check Valve. Here's a pic when I replaced mine, prior to installing a new carb. (Got it at CarQuest.) And yes, you can clearly see the EGR valve on the left.
P.S. "Random unused plug" connects to electric choke on the carb, but it looks like your incoming carb isn't electric - ?
Members with greater knowledge than mine will be along this evening to tell you about EGRs and chokes. I kept my smog intact because it was all working; plenty of owners chop it out and plug the EGR, though it's typically done with a plate, not a wad of epoxy.
Since my truck is virtually an '81 museum piece (as far as being UFW, or UnFutzed With), I've been thinking about doing a vac line photo series on my thread. I will do that tomorrow. It won't answer all questions for an 85, but it should help some. The GREAT thing about these engines is that there's almost nothing that can't be fixed, restored, redone, undone, etc.
Here's a couple more shots - the one on the right was taken last year, one of the few I can find with the air cleaner off. On the more recent (left) photo, the green arrow points to that choke connection.
Well i sure appreciate the help. I'll take a better look at your photos when im not on my phone. I may be closer to your 81 than you think because of the non feedback and dsII conversion. Thanks again!
Hey, my pleasure - the members here are the best, and while we didn't all get here on the same ship, we're all in the same boat.
Right under that electric choke connection is the heat tube that runs up to the choke.
On the vac tree, there's a hose on the fitting closest to that heat tube; it runs up and disappears, because it plugs in on the bottom of my air cleaner, to what I believe is the Bimetal Control Sensor. In the older pic you can see it unplugged because the air cleaner is off.
Because I know how it feels to be staring at your engine thinking, "What the...", I just shot a bunch of photos - give me a few and I'll post 'em here.
I'll assume that since you've converted to DSII, that you don't have emissions testing.
This can be good, and can be bad too.
Good side, is that you can do whatever it takes to get it running again and not sweat about it.
Bad side, is that people will fudge up emissions systems and have no idea what they're looking at/doing while they do it, all the while thinking they're getting more horsepower or better mpg, or doing something better than what the Ford engineers had in mind.
For your truck to run right, you've got too have a few things in place.
PCV, air breather/breather element, distributor vacuum advance, choke set properly, and no leaks.
Then, once those are taken care of, you've got to make sure there are no vacuum leaks whatsoever. Your truck will run like two dogs bumpin' if you got a leak.
Grab yourself a vacuum gauge to adjust idle mixture, and you can adjust ignition timing with one too if you don't have a light.
I'll have some photos of my engine bay later that you may find helpful.
My emissions equipment has been ripped off of my truck by the PO.
Pay attention to how you run the distributor lines.
One line off the vacuum advance canister. Then go to an F shaped fitting. One line runs to ported vacuum, the other line runs to manifold vacuum with a check valve between the port and the F fitting. You can see my two separate lines in the last photo. Yellow is ported, red is manifold.
You can see the ported vacuum line (just below the choke on the pass side of the carb) in WJ's photos. That's the correct port.
The big hole in the EGR spacer below your carburetor, that's where the AIR pump pushes fresh air into the exhaust. That big hole goes right above the down-pipe, and is the ideal location that Ford had for this year motor. On 87 to 96 models, they had an AIR rail with tubes blowing air directly into the exhaust ports. This replaced the "blow through" setup on the older combination manifolds.
If you want, you can remove the EGR spacer if you don't want to hook it back up, and remove the EGR pipe and find some way to plug the hole in the exhaust manifold (either break off the pipe, use epoxy like the previous dumbo, or find something with the appropriate threads to act as a plug).
Or, you can do like a lot of the members in the inline six forum on here do, and like I plan to do, and do a 4bbl swap with a set of headers.
The 3-port vacuum tree located on the firewall is for the transmission and the HVAC controls.
Port 1- A vacuum hose should connect to a round vacuum tee that is located on the passenger's side, near the heater core box. The other end of this round tee should have a vacuum hose that connects to a plastic black ball-shaped vacuum resorvoir located on the passenger's side inner fender. This stores vacuum to operate the HVAC controls when engine vacuum is low.
Port 2- A vacuum hose should connect to the vacuum tree that is screwed into the intake manifold, where the brake booster connects. This will supply manifold vacuum to that firewall tree.
Port 3- If you have a C6, one vacuum hose should connect to the transmission for the kickdown. If you have a manual transmission or an AOD, this port should be capped off.
The random unused plug in the engine compartment that connects to the alternator is for the electric assist portion of the stock choke cap. It plugs onto a spade located on the choke cap.
The stock choke system used a thermostatic "hot air" choke in conjunction with an "electric assist" choke. The hot air choke is the primary choke, and it must be hooked up correctly for the choke to operate. The electric assist is secondary and is designed to work only when the temperature is above 60 degrees. Above 60 degrees, the electric assist will help the choke come off sooner for better emissions. The hot air choke will work fine without it.
Thanks to everyone who has contributed so far. I am going to pour over all of this info tomorrow when I am near the truck, and when I have a better computer to see the pics.
Lariat, i have just a few questions for you right now, though. For one, i dont think i have a vacuum tree screwed into the intake for the firewall connections, and the brake booster is currently plugged in to the tree sticking off of the carb base. Also, you say the 3rd port is for the c6 kickdown, but im pretty sure my trans is an aod, because it has 11 bolts for the pan, but i do have a hose going to the trans on that 3rd port. Am i wrong about the trans?
Hmmm. It seems that after looking over my pics again, the booster is indeed hooked to the tree off of the intake manifold. My bad, disregard that part in my previous post. Oops. The other question still stands.
Well, here is the door sticker. The trans code is a W. I know it can't be a C6, because my pan is square shaped with 11 bolts in it.
That linkage on the manifold is currently disconnected. You can see in this photo:
Notice at the left of the picture where it is not hooked up. It is still hooked up everywhere else. The end by the carb looks like this:
I have no idea where that end would go to, but it has that screw on the end, which makes me wonder if it is adjustable or something. Reverse does not work right now. I don't know if this has something to do with it or not.
One more thing. For the distributor advance, I understand from the photos in this thread that it is teed off of the advance, and has 2 lines, one with a check valve. Where can I get one of these check valves? I want to hook everything up right.
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