Picked up a 'new to me' 1986 Bronco this passed weekend. When I picked it up I noticed the smog pump missing. PO said it had seezed on him and he took it out. From what I have seen under the hood, there is a blocked tub that goes to the back of the engine (3/4" ID). Reading the emissions label on the truck I see the vacuum line that goes to the diverter valve is pinched close. I'm assuming PO did this to fix the obvious vacuum leak.

Looking online at new smog pumps I don't see where the diverter valve will go. When I had my 1985 F-150 EEC-IV Carb, the diverter valve was mounted on the smog pump. The pics for the 1986 smog pump just has a tube coming out the back.

What I need, and I've been unable to locate, is a diagram or picture of what a proper 1986 302 EFI CA emissions system is supposed to look like. Can anyone snap a pic of theirs for me?

The Bronco was originally labeled for California sale and so I need to bring it back up to California 1986 specs. I'm in Cali and unfortunately this is a must. Besides EEC-IV thinks that stuff is still there and need to put it back.

 

So I've learned that it goes from:

AIR (Smog) Pump, to (I think)



AIR Bypass Valve (the left one in the image below I believe), THEN



AIR Control Valve, THEN TO 1 OF THE FOLLOWING



- AIR Check Valve them to Catalytic Converter, OR



- AIR Tube to Intake Manifolds


Another diagram showing EGR related components but not showing AIR Pump connections.



Still can't find how all this looks put together. I will verify AIR Tube is still installed (assuming so) as well as other components.

Unless someone is wanting to get rid of their smog pump and related equipment, I'm willing to buy it off of you.

 

Info in this thread may be relevant: https://www.ford-trucks.com/forums/1...of-engine.html

Some photos and diagrams in Post# 9. Not sure if your 1986 has the same plumbing as the 1994 in thread. F150/Bronco share the same secondary air injection components that inject air into the back of the heads. The F250/350 inject air into the exhaust manifolds.

 

That truly helps out a lot!! I know my year didn't use the combined bypass/diverter valve. They are separate components. Though this diagram and engine picture helps.

I think I have a better understanding.

Pump then Bypass Valve then to Diverter

Diverter then Check Valve (screw type) then AIR Tube, or
Diverter then Check Valve (slip on) then Cat

I'll take pictures of what I have currently today after work.

 

EDIT: So you can see the plumbing for the thermactor system on the back of the pulled engine in this photo. This gave me a good reference for how it's supposed to look.

So this helped me out too. It turns out the PO only removed the pump and bypass valve. I have the diverter valve and both check valves, 1 on the AIR pipe and 1 on the manifold.



Ordered a used pump/pulley and bypass off of ebay and will hope it works. If at least, I have the pulley now which seems to be hard to find for '86. '87 are all over the place. Don't know if they are interchangeable.

 

Too bad you live in Cali. Very little rust but well known for smog **** enforcement.

 

Yes it is. I mean I get it, clean air is nice to breathe but honestly. As long as the HC is down, why can't I do what I want?

 

Waiting for the used pump to arrive and decided to check the rest of the emission system. Looked under the Bronco and guess what I don't see?? The cats. Either of them. I remember there being two in my '85 F-150 so I imagine the same is true for '86. Yay..another expense.

 

Yeah.....Cali. emission converters are expensive.

 

I'm rebuilding my '86 F150. It's an unusual set up. I thought I'd go ahead and post this in case anyone else out there needs a picture.


Understanding Emission Controls, Ford Parts and Service Division Training and Publications Department, June1986