Off the charts HC - California Smog Fail

[saryon7]

The high hc is going to be from unburned fuel. There are a number of places this can come from.
A rich air/fuel mixture, misfire, too much fuel pressure, float level too high, leaking accelerator pump, choke not working properly, etc.

You asked about finding a missfire before. You can usually see the engine running rough. An easy way to check is to use insulated pliers and pull one plug wire at a time and watch the engine. When you pull a plug wire and the engine stays the same, you know you have found the cylinder responsible for the missfire. Normally pulling the plug wire should make the engine stumble.

I looked through my mityvac to find the diagrams, but I have no easy way of getting the manual to you. They list all the manuals online, but mine does not say what the model number is. They have great charts that will show you all kinds of things your vacuum gauge can tell you including valve leaks. See if you can find one of these charts.

 

[CruiserStuff]

Did a compression test today and found:

#1: 120
#2: 105
#3: 105
#4: 120
#5: 120
#6: 120

Hmmm.....

Also, had someone look at the plugs I replaced and he seems to think that I need to replace the valve seals.

Planning to do a leak-down test tomorrow and will report back. Heading to pick up a Harbor Freight timing light and tach right now.

Lastly, noticed that the fuel in the carb window is a bit over half.....not much, though. Is that cause for concern?

 

[CruiserStuff]

Update: Found that the timing was WAY off. In fact, the BB wasn't even visible in the inspection window.

Unrelated, though, I went to attach a ground wire on the coil/ignitor assembly and failed to disconnect the battery first. Next thing I know, I had smoke and a small flame coming from my loom. Dang it! Fortunately, I think the damage was limited to the section between the coil and well in front of the firewall. Spent about 4 hours yesterday splicing in new wires. Hopefully will have it all back on line today. Geez....

 

[Pin_Head]

It sounds like you are missing the fusible link that would have prevented that kind of damage.

 

[CruiserStuff]

You would think, right?! I do, though, (lo and behold) have the fusible link in place. Here's the thread showing: https://forum.ih8mud.com/40-55-series-tech/354030-almost-had-me-car-cue-2.html (starting around Post #39).

You'll see (from the linked thread) that I had this problem a few years ago and I still had all the wire and connectors (leftovers) to rebuild the affected portions this time. Not sure why the fusible link didn't prevent this, though.....any ideas?

Question, Pinhead: I have the vacuum retard dizzy setup....when I'm setting the timing, should I be disconnecting and plugging the vacuum line that comes from the dizzy?

 

[Fast Eddy]

I have the vacuum retard dizzy setup....when I'm setting the timing, should I be disconnecting and plugging the vacuum line that comes from the dizzy?

Regardless of retard or advance dizzy, you should disconnect the vacuum line when setting the timing.

IMO, a retard timing dizzy should get a bb in the vacuum line to it permanently. My '78 has one and it passes easily.

 

[CruiserStuff]

Got the wiring repair completed and the truck fired right up. Looks like everything is okay.....and now the engine actually stops when I turn off the key! Miraculous....

Truck sounds great at idle and performed very well on a short test drive. Gonna take it back to the smog nazis in the morning to see if there's any improvement on the HC levels. Will report back.

No one has answered whether or not the high float level is/could be significant. It isn't quite 3/4 up the sight window, but definitely over half. Anyone with input? Thanks guys...

 

[Coastline]

I just caught this thread.
What I did was to take my 77 to a local auto shop here in Cucamonga that works on a lot of vintage cars and also, does smog. It passed with flying colors. Of, course, the motor had less than 2,000 miles on it but it also has Downey tri-Y headers (with CARB Sticker) and a DUI dizzy. But still, after spending 3 1/2 years of frame-off re-do, I don't want to putz with things like smog. I paid Tim to do what he and his mechanics know how to do. $60.00 out the door with paper work in hand. Afterward, I went back and had him reset the dizzy so that it runs without backfire or dieseling.

I suggest finding a local shop and let them take your guesswork out of the equation.

 

[CruiserStuff]

Coastline - Thanks for the input....that was going to be my next move (taking the rig to a local shop)....but that is not necessary because (drumroll) I PASSED this morning! In my opinion, this is proof that there is a God!

Drove for about 1/2 hour before the test, took it in without turning it off and tested it right away. Had to do some minor carb tweaking to get everything within limits, but it passed....completely above board!

Here are the numbers:

RPM @ 1077 - %CO2=11.0, %O2=4.3, HC=81, CO=1.45
RPM @ 2399 - %CO2=11.7, %O2=3.6, HC=14, CO=0.89

Thanks to everyone for their input and help. As always, it is very much appreciated!

 

[Fast Eddy]

I PASSED this morning!

Here are the numbers:

RPM @ 1077 - %CO2=11.0, %O2=4.3, HC=81, CO=1.45
RPM @ 2399 - %CO2=11.7, %O2=3.6, HC=14, CO=0.89

There is no greater feeling, eh?

Please post up the limits as well. Were you required to go to a star station?

 

[DSRTRDR]

Coastline - Thanks for the input....that was going to be my next move (taking the rig to a local shop)....but that is not necessary because (drumroll) I PASSED this morning! In my opinion, this is proof that there is a God!

Drove for about 1/2 hour before the test, took it in without turning it off and tested it right away. Had to do some minor carb tweaking to get everything within limits, but it passed....completely above board!

Here are the numbers:

RPM @ 1077 - %CO2=11.0, %O2=4.3, HC=81, CO=1.45
RPM @ 2399 - %CO2=11.7, %O2=3.6, HC=14, CO=0.89

Thanks to everyone for their input and help. As always, it is very much appreciated!

getting the engine nicely hot before the test helps

 

[CruiserStuff]

There is no greater feeling, eh?

Please post up the limits as well. Were you required to go to a star station?

Oh, it was a joyous day! Let's see, here are the numbers with the limits:
RPM @ 1077 - HC: MAX=250, AVE=73, MEAS=81 CO: MAX=2.5, AVE=0.50, MEAS= 1.45

RPM @2399 - HC: MAX=200, AVE=67, MEAS=14 CO: MAX=3.00, AVE=0.90, MEAS=0.89

No, this was a regular smog station, not a star station (to the best of my knowledge).

 

[CruiserStuff]

getting the engine nicely hot before the test helps

Yes, it does! Thanks!

 

[surfpig]

Oh, it was a joyous day! Let's see, here are the numbers with the limits:
RPM @ 1077 - HC: MAX=250, AVE=73, MEAS=81 CO: MAX=2.5, AVE=0.50, MEAS= 1.45

RPM @2399 - HC: MAX=200, AVE=67, MEAS=14 CO: MAX=3.00, AVE=0.90, MEAS=0.89

No, this was a regular smog station, not a star station (to the best of my knowledge).

Nice!



My '77 55 always passed, sometimes just barely. I found that the timing was critical. I tried to get it a few degrees beyond the mark, seemed to have the least emissions at that setting. It was borderline pass at the 7* mark.