1985 f150 6-300
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
I haven't worked on any sixes before, but some of the pieces are common to every engine.
#1 is the EGR valve. It puts exhaust into the engine for emissions reasons. Looks like it's disconnected.
#9 is the fuel filter.
#7 looks like a throttle position sensor.
#3 is the choke housing.
#6 is the hot air tube that warms the choke housing.
#4 looks like some sort of idle control motor.
You know what all this means? You have a computer controlled engine, and all the computer stuff has been disconnected. If you want to it run correctly, you are going to need to get a distributor and a carb for a older engine that did not have computer control. Right now you have no timing control at all, no wonder it gets lousy mileage and has no power.
#1: Egr Valve.
#2: is a check valve for the Thermactor System. Only lets air from the air pump travel in one way, and does not let exaust from the manifold or the exaust pipe from backfeeding to the air pump.
#3: Choke Housing.
#4: Electronic Dashpot. For A/C and/or cruise contol. Also helps to prevent stalls if you let off the excelerator quickly.
#5: Fresh Air tube for choke stove. Supplies Filtered air to the choke stove located in the exaust manifold.
#6: Choke Stove return tube. Brings the Heated air back from the choke stove. #5 and #6 are hooked in a loop. Filtered Air leaves #5 and returns heated #6. Keeps the choke warm and funtioning correctly.
#7: Throttle Position Sensor, or what's left of it.
#8: Feedback Solenoid. Adjusts fuel/air mixture ratio, in conjunction with the O2 sensor not pictured. (This is why it's drinking fuel, It's disconnected)
#9: Fuel Filter.
If you are bringing this into california, you have got your work cut out for you. This would fail miserably, and be designated a gross poluter.
You are also missing the thermactor air intake manifold. Those ports plugged up with those bolts is where it connects.
More comments in the next post....
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
.
#2 is a another vacuum port, but I don't know what it went to. It should be plugged.
#3 is the fresh air port for the #4 warm air choke tube port. #3 runs down to the exhaust manifold, runs through the exhaust manifold were the air is warmed up, and then goes up to #4 were the warm air enters the choke housing, to make the choke and fast idle kick off. There is a controlled vacuum leak inside the choke housing that sucks the air through this system. #3 port is located right below the air filter so it pulls filtered air through the system.
more comments in following post....
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
Thermactor Air Bypass, and Thermactor Air Diverter solenoids. Controls the Thermactor Air bypass, and Thermactor Air Diverter valves. (Looks to be missing)
This hooks up to #2 in the previous picture, with a 3/8 in hose.
Confirmed.
And #4 is the ports for the Thermactor Air intake manifold. (Missing) Described earlier...
#2 is the PCV valve. This needs to be hooked up to keep the inside of the engine clean. Someone with this style engine will probably know where the vacuum line hooks for the PCV.
#3 Is the oil fill cap and also the fresh air intake for the PCV valve. When the PCV valve sucks the nasty stuff out of the engine at the rear, fresh air enters the pipe on #3. The pipe on #3 hooks to the air cleaner.
And #4 is the ports for the Thermactor Air intake manifold. (Missing) Described earlier...
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
Wow, thank you so much Franklin. I went out this morning and pulled the Carb off. The Dist is for sure computer controlled. There are no vacuum lines that could connect to it. I spoke with a cousin of mine and he said I should either 1. Convert to an older carb and dist set up (i assume this means goto vacuum line dist) 2. get a regular carb and get duraspark system installed.
I am interested in what kind of carb is it that I should ask for? I do not have a Chilton manual on it yet, luckily the library does and i think ill pull some copies from it. The other thing is the vacuum solenoid bank i wonder if it even works. When I checked fro vacuum from any of the lines it seemed like i was getting little to none. i almost want to bypass anything that would give me a failure point. try and route it so everything is in its simpalist form.
So things I need to know: What kind of Carb should I be looking for to replace my own?
What kind of Distributor should I look for?
Will these changes affect smog for California?
My concern with going to an older style, is that when I register,title,and smog this thing, will I risk not passing smog? Will the state require the emissions electronics, though not used, to still be wired up? Will all vacuum lines, thought not possibly all used, need to still be hooked up for visual inspection?
I know im asking a lot, and im sure that some of its common knowledge to a mechanic, but again, this is a hobby for me and im learning the ropes.
Thank you for any and all help.
Also, I disconnected all vacuum lines and wire harness when I got it safely to my car port. That is why everything was disconnected. I didnt want to try and fix a previous mistake, ide rather start fresh. Esspecially when it comes to vacuum.
-Casey
Thank you for any and all help.
Also, I disconnected all vacuum lines and wire harness when I got it safely to my car port. That is why everything was disconnected. I didnt want to try and fix a previous mistake, ide rather start fresh. Esspecially when it comes to vacuum.
-Casey
This is going to be challenging, but not impossible. Be glad to help.
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
Yeah my cousin was saying as long as I hide all unused hoses and wires (be it cut them free or modify it to look as though it never exsisted) is the only way to pass the visual inspection. My big concern is what happens to the emissions going to the old set up. Yeah I am in sacramento, carmichael to be specific. Ive never owned a vehicle that had to go though a smog process. This is my first vehicle that ive attempted to put together myself.
Some more information on the previous owners workings with the truck.
He bought this truck, fried the motor, bought a rebuilt motor of same year. He took the carb from a parts truck of same engine and body. He bought a new dist but it was for the same he took out, not modified. He and his non mechanic father put the motor in and wired it back in. Including vacuum lines. When he did this the truck seemed to run fine but he did complain that it was getting poor gas milege. He said it was getting about 16mph on the highway, if that. about 12 around town. When I picked up the truck it had a poor idle, so i chalked it up to a timing issue or a vacuum issue. I drove it from Reno NV to Sacramento CA. On the way it lost power and seemed to run rougher. If I hit a hill, in fouth it lost about 5mph every 5-8 seconds. On the big hills I would have to downshift to 3rd and climb at 35mph to the top, then back to 4th and ide coast it down at 70mph.
When I got it home, it would not stay idled. It would die if I didnt gas it alittle. The next morning it wouldnt even start without some serious gas pedal play. The whole time ive had it, it has smelled as though its running rich, and the amount of fuel I was losing made me think that the choke was closed and I wasnt getting any air. But when I had it home I found the choke was open and not shutting even the next day.
So I began to search for a disconnected vacuum line, since most of the lines were not properly secured. During this investigation i found 3 lines not connected to anything, and nothing near by to connect to. When I plugged them with my thumb to see if any suction was present, i found none. Also, at this time I found that a couple wiring connections to the carb had been melted together due to resting on the block. One of which was the thottle sensor. Btw, this whole time not a single idiot light came on.
I traced every line from it beginning to end and found only the three that were just open to nothing. One was the coming from the carb, and thank to you guys I know what it did, was the fresh air port it was just laying loose. From the pcv valve there was a large hose that split off to a smaller hose and a larger hose but none had any suction of any kind.
So, as of now, what ide really like to do is not figure out what is wrong, but look at this truck like this - Here is a rebuilt motor with no carb and all vacuum lines and electrical need to be replaced. What kind of carb should I put on? Again keeping in mind I want it to smog, in California. In addition, money is a factor so preferably nothing too extravigant. I am going for simple and stock but I dont want to go faulty stock. Because I am reading that this particular carb, even if rebuilt can get you into trouble time and time again due to its poor design.
So, as of now, what ide really like to do is not figure out what is wrong, but look at this truck like this - Here is a rebuilt motor with no carb and all vacuum lines and electrical need to be replaced. What kind of carb should I put on? Again keeping in mind I want it to smog, in California. In addition, money is a factor so preferably nothing too extravigant. I am going for simple and stock but I dont want to go faulty stock. Because I am reading that this particular carb, even if rebuilt can get you into trouble time and time again due to its poor design.
So hopefully thats answers it. I plan to take the truck down once its running to a muffler guy I know and get something pretty but hopefully emissions helpful.
I went to that website www.ezwiring.com and talked to a sales guy about which wiring set up i wanted, i didnt know because i wasnt sure what exactly he meant by options. Of course my response must have been crap because he said I need the 185 dollar wiring harness (most expensive one they have).
The vacuum hoses that I took off are all new. The Solenoid junction at the firewall has 5 hoses going to it, I do not know if that is working properly. I would assume that the computer opens and closes those solenoids to allow vacuum to the differant lines. So I may just see if I can replace that just to I eliminate its possibility of failure.
I went to that website www.ezwiring.com and talked to a sales guy about which wiring set up i wanted, i didnt know because i wasnt sure what exactly he meant by options. Of course my response must have been crap because he said I need the 185 dollar wiring harness (most expensive one they have).
The vacuum hoses that I took off are all new. The Solenoid junction at the firewall has 5 hoses going to it, I do not know if that is working properly. I would assume that the computer opens and closes those solenoids to allow vacuum to the differant lines. So I may just see if I can replace that just to I eliminate its possibility of failure.
Again, I would go stock, but I dont want a Ford failure. Ide rather get the fix for it and call it done.
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
I have been through the smog checks many times out here, and it really does depend on who you see. They are mostly interested in the tailpipe results though. Plus, on a older truck like this, the smog tech probably isn't going to know that a 1986 F-150 has a feedback carb and not a vacuum distributor. I think that you'll be OK as long as it passes the sniffer and of course who happens to be working at the smog check station.
With a state that pressurizes your gas tank to see if the evaporative emission system works, and checks the functioning of the gas caps, to see if they hold pressure... I wouldn't risk tampering with it myself. Not worth the risk.
Post Fiend
Joined: Mar 2002
Posts: 19,402
Likes: 38
From: Bonita Springs FL
Heh. Reminds me, the last time I had my Bronco smog checked I took it to a test-only station. There was an asian guy working the machine and I could barely understand him. He eventually was able to tell me that my gas cap wouldn't pass emissions, and the computer needs to see that the gas cap passed in order to transmit the results to the CA DMV. He screwed on one of his extra gas caps for me so I could pass.
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New User
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Thermactor Air Bypass, and Thermactor Air Diverter solenoids. Controls the Thermactor Air bypass, and Thermactor Air Diverter valves. (Looks to be missing)
This hooks up to #2 in the previous picture, with a 3/8 in hose.
Confirmed.
And #4 is the ports for the Thermactor Air intake manifold. (Missing) Described earlier...
This hooks up to #2 in the previous picture, with a 3/8 in hose.
Confirmed.
And #4 is the ports for the Thermactor Air intake manifold. (Missing) Described earlier...
I'm trying to chase down an intermittent miss on my truck ('95 300 straight six), and can't figure out what it is. I noticed that this #3 on my truck isn't tight in the hole, and is wiggled out a fair amount..should I be worried about that, or just make sure it is in there snug? If it were loose, could it cause the problems I've been having?
Thanks-
Post Fiend
Joined: Jul 2004
Posts: 8,786
Likes: 28
From: Northern California
If it's the number Four in the last picture, then yes that could cause an intermittant miss. The ports for the thermactor pipe are directly connected to the exaust valve ports on the head. If it's bad enough, it will cause a severe exaust leak, and cold air sucking into the valves can damage them or warp them slightly causing a miss. This system is normally closed to the exaust ports with the truck warm and is only used when the truck is cold.
Number 3 is the oil cap and fresh air hose from the air cleaner. This should be tight enough to keep dirty air out of the engine, but it wont cause a miss if it leaks infiltered air slightly. But it's a good idea for it to not suck dirty air.
Number 3 is the oil cap and fresh air hose from the air cleaner. This should be tight enough to keep dirty air out of the engine, but it wont cause a miss if it leaks infiltered air slightly. But it's a good idea for it to not suck dirty air.
New User
Joined: Dec 2009
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If it's the number Four in the last picture, then yes that could cause an intermittant miss. The ports for the thermactor pipe are directly connected to the exaust valve ports on the head. If it's bad enough, it will cause a severe exaust leak, and cold air sucking into the valves can damage them or warp them slightly causing a miss. This system is normally closed to the exaust ports with the truck warm and is only used when the truck is cold.
Number 3 is the oil cap and fresh air hose from the air cleaner. This should be tight enough to keep dirty air out of the engine, but it wont cause a miss if it leaks infiltered air slightly. But it's a good idea for it to not suck dirty air.
Number 3 is the oil cap and fresh air hose from the air cleaner. This should be tight enough to keep dirty air out of the engine, but it wont cause a miss if it leaks infiltered air slightly. But it's a good idea for it to not suck dirty air.
Anyway, I will leave this thread alone now since it has nothing to do with this..but..if you happen to have an idea of what I could check, let me direct you here...
https://www.ford-trucks.com/forums/9...tent-miss.html
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L6 Prob... Plz Help!
Ok so I am an inline 6 guy if ever there was one. Both the cummins diesel Jeep 4.0L Ford 300 and the Chev 292-CID. I have been running a Ford 300 L6 for a year now and it has ran excellent... till about a week ago. I have tried every thing I can think of and it just runs like crap. (Rough idle, low power, inconsistent idle, ect.) I have replaced the carb, changed oil, replaced spark plugs, wires, cap & roter, and coil. Have fair compression in all 6 cylinders, the only thing that makes it run better is to open a vacuum line. Any ides or thoughts would be helpful. Thanks
Moderator
Joined: Nov 2007
Posts: 22,415
Likes: 92
From: Denver Metro Area, CO
temperature and air cleaner removed, look down into the throat of the carb, the
choke plate should be fully open and you shouldn't see any gasoline dribbling
down inside. Report back what you find.
Freshman User
Joined: Mar 2012
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I came across this thread while looking for help about PCV connections. I have a 1985 4.9 300 with a feedback carb just like Origin. The bottom hose running from my PCV is connected correctly, but the smaller, top hose goes to nothing. Anyone know where this hose should connect to?
Thanks
Thanks
Moderator
Joined: Jan 2001
Posts: 56,950
Likes: 2,718
From: Virginia
If you are talking about a smaller nipple made into the PCV valve plastic piece, then it may not go to anything. The parts stores sell universal fit PCV valves, and this smaller nipple is covered over with plastic. If you need it, you take a knife and cut the tip off to open it up, and then hook the original hose to it. If your vehicle does not have a smaller hose there, you leave it alone and it stays plugged.
On some vehicles, you have to cut the smaller connection, and a smaller hose hooks there and leads to the charcoal canister to purge the fumes from it. But you will need to look at the sticker on your radiator support to verify if you have this connection at all. Ford used lots of variations in their smog connections.
On some vehicles, you have to cut the smaller connection, and a smaller hose hooks there and leads to the charcoal canister to purge the fumes from it. But you will need to look at the sticker on your radiator support to verify if you have this connection at all. Ford used lots of variations in their smog connections.