failed deq 78 620

[datzenmike]

I followed the link Klassic posted up and here is what their diagrams have:

 

 

Blue circle is the pipe were talking about

Green line is the hose that is missing from that capped pipe

Red circle is where the green line ends

Red oval lists it as a PCV

 

 

 

 

All that shit was missing on mine so I cant say first hand where everything goes... just know thats what the manual says.  :confused:

.

 

This picture is totally wrong. That is part of the air pump as mentioned. The vent hose from the block to the PCV is just below the anti backfire valve marked 6 (which is correct)

 

 

DattoChinook your vacuum advance and EGR are not connected. There should be a vacuum outlet on the valve cover side of that weber carb. It should go to the distributor and that fitting on the thermostat with the two ports on it and from there over to the EGR.

[datzenmike]

You can see the EGR line goes over beside the choke heater and is not connected to anything...
 


Thermal vacuum valve opens when engine warm and sends vacuum signal to the EGR



Carbon canister collects gas vapors and store them untill motor is running



EGR lower right









 

[DattoChinook]

You can see the EGR line goes over beside the choke heater and is not connected to anything...

 

 

Thermal vacuum valve opens when engine warm and sends vacuum signal to the EGR

 

 

Carbon canister collects gas vapors and store them untill motor is running

 

 

EGR lower right

 

 

 

 

 

 

 

 

Thanks DatzenMike.  So I am still confused a little on where I need to run vacuum hoses.  From carb vacuum advance to distributor and then to one of the nipples by the thermostat (with a t??)?  Then another line out of the other nipple by the distributor and to the egr?

 

So the carbon canister only has one line going to it.  What else goes to it?

 

So as far as the check valve that I am missing...  Will that fix my exhaust leak if I install one?   Or should I just buy a (non rubber hahaha) cap to go over it?

 

Is it possible for me to pass the deq without a smog pump?

[datsunaholic]

If they never open the hood, it's possible. If they open the hood, you'll never pass with all that stuff disconnected and missing.  You'd need the factory air cleaner too, to at least hide the weber.

 

But you're running over-rich, which may take more than just hooking up vacuum lines.

 

Part of the issue is that the Weber doesn't have the required ports to run the EGR vacuum- Webers usually only have one ported vacuum line (for the distributor vacuum advance).  The EGR is ported from a completely different source than the distributor, and the Hitachi had that port.

 

The EGR mostly just controls high NOx emissions.  It doesn't do much for CO or HC, and in some cases actually increases them by a TINY bit.

 

The Air Pump, OTOH, helped with high CO readings.   Not so much with high HC, though it'll have some effect.  That's a case of unburnt fuel- could be timing, could be a case of the Weber is simply jetted too rich.

[DattoChinook]

They looked all in the hood at the deq and didn't say anything... just failed for emissions and not inspection.

 

I see why he took off the smog pump now... the air valve is too big to fit on that pipe with the weber there. Weber is totally in the way. I am gonna just gonna have to cap it.

[DattoChinook]

So I hooked the vacuum lines up how I thought they went...  Advance from the carb to a T  One part of the t going to the dist.  one part going to one of the nipples by the thermostat.  Then another line going from the second nipple by the thermostat to the egr.  Is this right?

 

It seems to idle better but it hesitates now and then now when I give it gas. 

 

I capped the inlet pipe for the smog pump with a pipe cap.  It is pretty close to the fuel line.  Not touching but less than an inch.  Kind of worried it is too close to the fuel line.  It got pretty hot just taking it for a test drive.

[KlassicMotion]

I know nothing about emisions, as Kansas is exempt, but what would happen if he just leaned the air screw out on the Weber for the emisions test?

 

Or, maybe someone in your area has a Hitachi carb they could loan you for the test......

[DattoChinook]

I went back to deq.  Failed but not as bad. 

 

1st pass  HC (220 or below)  344    CO (1 or below) 1.6562                                 

2nd pass HC (220 or below)  350    CO (1 or below) 0.8356

 

The first time i took the test it looked like this

 

1st pass  HC (220 or below)  466    CO (1 or below) 1.2519                               

2nd pass HC (220 or below)  343 CO (1 or below) 5.8469

 

I figure I didnt hook up vacuum lines right.  It ran like crap and kept studdering when accelerating.  I took all the vacuum lines back off after the 2nd deq test and it runs like it used to.

 

I have no idea what I am doing or how to fix this.  About to give up.  When I bought this my parents lived in Salem and I planned to register it there if I had deq issues..  They just moved back to the Portland Metro area and now I am SOL.

 

I have family that Lives in Eugene and St Helens and figure I could change my address to either place and not have to do smog.  But the DMV will require utility bills or a lease or something.  Sounds like trouble getting involved in doing that...

[Tristin]

I have an old hitachi you can have for the price of shipping. Give it a decent rebuild and you can throw all the stock crap back on it. 

[KlassicMotion]

To get it to run better, put the vacuum line from the carb, back to the vac advance on the distributor, ONLY.

[KlassicMotion]

 

I have an old hitachi you can have for the price of shipping. Give it a decent rebuild and you can throw all the stock crap back on it. 

What year is yours from?  Did they change through the years?  I know for other Makes, the later years had more vac lines running to the carb.  Not sure on the Datto.

[DattoChinook]

I'd really appreciate that. Thanks! Paypal for the shipping? I'm in 97007. I think I need the airpump to get it to pass even deq even with the hitachi?

[Tristin]

I have no other smog equipment... just a stock carb I just removed. All of the stock stuff was removed when I bought the car. 

 

 

 

If youre worried about changing over the years, if someone will post how many vac lines or if they didnt change... I can take some pictures Sunday or something (next time I see the car) and post them up for you to look at. 

[DattoChinook]

Ok I will try just doing the one vacuum hose. Thanks

[datzenmike]

HC is unburnt gas.

 

Is the air filter dirty? Clogged will act like the choke is on.

Is the choke shutting off by opening fully when the engine is warmed up?

Timing set to 12 BTDC?

Check your valve lash.

Is the engine running about half way in the normal run range on the gauge?? A cold engine will pollute.

[flatcat19]

Tristin's Hitachi is from an L16, maybe? This guy has an L20B. 

 

Someone posted a vacuum diagram. Follow that the best you can. 

[Tristin]

Tristin's Hitachi is from an L16, maybe? This guy has an L20B. 

 

Someone posted a vacuum diagram. Follow that the best you can. 

 

I did follow the diagram... look how well that worked out earlier in this thread :rofl:

 

 

I have no idea what its from. Its been pieced together over the years... if they are different then no need to send it along.

[KlassicMotion]

3 pages now, I don't remember what you've done...

 

Like Mike is saying;  Have you tried a full tune up yet? 

 

Set the valves, tune the carb (as per the instructions I posted earlier), set the points/dwell, set the timing, spark plug gap, check for vacuum leaks.....   All that is a must before spending any more $$$$, or worrying about what is missing from the engine. 

[Laecaon]

Or how about a catalytic converter?