Emissions and vacuum diagram for 1978 F350

[TheDesertRat]

I'm looking for a nice clear scan of a smog/emissions/vacuum diagram for a 1978 F250. Or for an F150 with a 460. I have a 78 F150 that has a 460 swapped in and I have to put all the Ca. smog parts on it in order to get the smog ref to pass it. I have this one but it isn't clear when I blow it up. I have to locate and install all the smog parts that would have come on a light duty truck in California in 1978 which should include the F150 and F250 (or any F series under 8000 GVWR). If somebody knows where this picture came from, I would like to know that. I believe it could be from a Mitchell catalog.

 

[Mil1ion]

knew what you were looking for and have had it scanned and ready for you for days now.

Now Just keep clicking the images until they are real close ups.

They end up being very large after you click full screen and then one more click

wrong image

 

[TheDesertRat]

I have both of those pics in hi-res, perhaps from you previously. If you look at both of those pics and the one I posted, they are different. I am wondering why the one I posted above has more junk on it than the other two? For example, the vacuum canister is on the top pic but not on the other two.

 

[Mil1ion]

above post edited

I'll rescan it for you larger

 

[TheDesertRat]

That webshots site is driving me nuts. I am a member there but now they want you to download their program with their proprietary picture format. I just want it in .jpg. Another Sony type company trying to reinvent the wheel I suppose.

 

[Mil1ion]

see your PM

 

[TheDesertRat]

We are PM'ing each other but for the benefit of others, do you know why that scan shows a vacuum canister and the other pics don't have it? I wonder if the other pics are 49 state diagrams and that one is for Ca. only? And by the way, thanks for all the help.

 

[Mil1ion]

One is Preliminary and the other... the one above is Final

 

[Mil1ion]

The last one is more for the E-350 since it has more vacuum actuated things

I have another one for the F150-F250-F350

 

[TheDesertRat]

Ok, so I would assume I would use the final. Although, I do have some scans from the Mitchell catalog and the list of required items to pass Ca. smog in 1978. Finding all the parts though has been quite the headache. I've hit the Stockton Pick n' Pull twice so far and had great luck. But, as I posted elsewhere I just found that my heads don't have the air ports in the back. So, I may have to source different heads.

 

[TheDesertRat]

The last one is more for the E-350 since it has more vacuum actuated things

I have another one for the F150-F250-F350

I definitely need the F150-F350 one.

 

[Mil1ion]

It's up and sent to you

 

[TheDesertRat]

Outstanding help, thanks again.

 

[Mil1ion]

Tell them on the other site how much better this site is

 

[5thDimension]

too many little questions

Dessert Rat, did you get your truck smogged? I'm in a somewhat similar situation, I purchased a '78 F350 flatbed, it's passed smog a couple of times (once when I got it, again about a year ago) but I'm certain the vacuum lines aren't setup properly and want to get it right. I also have the 460.

I'm wondering a few things: 1) what vacuum diagram did you end up using, and can you share it, or just draw a schematic of what was approved on a piece of paper and post it? 2) how do you go about finding parts like the venturi vacuum amplifier, vacuum delay valves, and vacuum control valves? 3) how do you get specs on what they should be? For example, what delay should the vacuum delay valve(s) provide? What temperature do the vacuum control valves work at? How many ports should be on the vacuum control valves?

I've done a lot of reading and looking around to piece this info together but I'm not quite there yet.

Million, I've seen a lot of your posts with great diagrams (thanks)! Do you have one that's applicable to my vehicle, do you think?

Another question--Million, I found a small picture of a vacuum routing diagram in your pictures, under 79 460. Is that applicable to a 78 F350? I don't see any choke pull-off on the carb. My truck didn't have one when I got it but I was assuming someone pulled it off and it originally had it (because I have trouble with it starting cold).

 

[BKW]

Million, I've seen a lot of your posts with great diagrams (thanks)! Do you have one that's applicable to my vehicle, do you think?

Another question--Million, I found a small picture of a vacuum routing diagram in your pictures, under 79 460. Is that applicable to a 78 F350? I don't see any choke pull-off on the carb. My truck didn't have one when I got it but I was assuming someone pulled it off and it originally had it (because I have trouble with it starting cold).

You are leaving out one very important detail.

Where was the truck sold new? If in CA, be aware that CA vacuum diagrams and some of the smog parts are CA only!

Look on the Warranty Plate (located on the left door face below the latch) for the DSO code.

If it's 71 or 72, it's a CA vehicle. These same DSO codes also apply to Passenger Cars, Bronco's, Econolines.

Desert Rat: What engine does your truck have? If a 351M or 400, look for 1977/78 LTD/Mercury Marquis / 1977/79 LTD II/Ranchero/T-Bird/Cougar/Town Car/Mark V and get the parts from them.

If a 460, 1977/78 only. No 460's in Passenger Cars after 1978. The 5th digit of the Passenger Cars VIN is the engine code: A = 460 / H = 351M / S = 400 // The first digit of the VIN is the year.

These are the same parts as used on trucks...same Evap Emission, PCV, EGR and etc.

btw: Passenger Cars have a VIN plate on the left corner of the dash, visible thru the windshield...So you don't have to raise hoods and etc to find out what engine they have.

 

[Mil1ion]

78 F350 460 49 state calibration code is 8-97-R0

For 77's and 78 People can look them up here

http://mil1ion.clubfte.com/78CalibrationCoding&Tune-upSpecs.html

Hey Bill you are ignoring me again.... Please Stop that

 

[5thDimension]

thanks, need to check

Bill,

thanks, I need to check--will do so when the sun comes up! I think it is a CA vehicle but I didn't know how to check.

Million,
the calibration code you gave--is that for the engine? When I first got the truck I had a shadetree mechanic work on it and he swapped the engine out with a rebuilt 460 from a '72 Tbird, keeping all the original smog equipment from the truck motor. The sticker on the motor is therefore not going to be much help. I didn't realize it even existed until he got rid of the old motor, so that info is lost. The sticker on the swapped-in motor is there but he painted over it enough that I can't really read it.

I appreciate your replies and info--thanks!

 

[5thDimension]

calibration code and specs from Million

Million,
I spent a few minutes pouring over the info in the link you posted.

From what I can tell by reading it (correct me if I'm wrong), the 49 state and CA specs, though a different number, are the same. I didn't see any differences in carb settings, spark plug gaps, etc.

While helpful for setting the carburetor up, which I am grateful for, it doesn't answer my questions about how to know what temperatures activate the thermal vacuum switches (ported vacuum switches?), how many and what type of vacuum delay valves should be there, how many hoses should be able to be connected to the ported vacuum switches, etc.

I've gone to a smog place and asked them, they let me look at their books, but there was really no good answer. I'm sure there's a good answer, I just haven't found it yet. Fortunately I have another several months before the next smog will be due again (December). I'd love to just have it nailed the next time.

I have an advice question too--I got a NOS carb (motorcraft 4350) that was made for a police jeep, it was sitting in a warehouse on a shelf all these years, and I was lucky to purchase it via ebay. Would you recommend rebuilding it before trying it? Just trying it?

I have some experience rebuilding carbs but would rather not mess with it if I don't need to. On the other hand, I'm thinking at a minimum that the main jets will need to be adjusted since it was for a jeep (which from what I can tell was a 400 engine).

The carb I have on the truck is doing a fine job except for cold starts. I've been holding off changing it until I get the vacuum stuff correct.

 

[Mil1ion]

Well you need to start posting casting codes from those engine parts to maybe help narrow this down.

The parts that you talk about have been produced to perform accordinging to the specs they were built under.

Any measurements that are required for operation would be listed in the OEM service manual in the corresponding topic.

I can check my 78 manual if you wish.