So I hate to do it but I thought I would throw it up here because the Mud knowledge base is so deep. I have read almost every emissions thread I can find, and I am determined to get this figured out. I'll give as much detail as I can. First of all the emissions readouts:
HC: Pass
NOx: Pass
CO: 143 GPM, limit is 45 (rich right?)
I live in Colorado and our town is at roughly 6500 ft elevation.
Brand new rebuilt 2f, less than 100 miles on it.
Rebuilt carb (well i rebuilt it 2 years ago when I first started attacking this problem, it sat for 2 years while I was getting the engine rebuilt)
Brand new Cat.
Rebuilt smog pump by B-Z rebuilders in California.
All brand new vacuum hoses that are presumably hooked up right. (i'm in the midst of policing my work right now)
ABV works according to tests in FSM. Also inlet hose to smog pump has suction, and the bypass hose is not blowing any air out back into the air filter.
Brand new plugs, distributor cap and wires.
Timing set to 10* with the vacuum hoses unplugged. HAC works to bring the timing up to 16* when plugged in.
Idle mixture screw set using highest Vacuum with idle speed screw set to about 450-500 rpm. About 18 inches.
No vacuum leaks, my vacuum gauge shows 18 inches steady at an idle of 650-700 rpm. This is at 6500 ft elevation.
Choke shows fully open when hot.
Brand new air filter.
Oil has only the mileage on it since rebuild.
New rear brakes might be dragging a bit, just installed new shoes and drums.
Stock size jets.
Fuel in Carb is a little bit higher than the middle of the sight glass during idle.
H55f, so a five speed for the emissions test.
All I've found so far is that the vacuum hoses to the HAC, the ones that go to the Upper Left and Upper right were reversed. I know that this could cause a rich condition, but i'm almost 3 times over the limit, so I'm not sure this will solve it. The CO on the speed graph is high at speed not at idle, so i'm also not sure changing the idle mixture screw to lean it out some more will help.
I'm about to take it for the 3rd test after I switch the HAC vacuum hoses. If it fails then I guess I'll throw some E85 in it? Thanks for all the help on here!
Chad
HC: Pass
NOx: Pass
CO: 143 GPM, limit is 45 (rich right?)
I live in Colorado and our town is at roughly 6500 ft elevation.
Brand new rebuilt 2f, less than 100 miles on it.
Rebuilt carb (well i rebuilt it 2 years ago when I first started attacking this problem, it sat for 2 years while I was getting the engine rebuilt)
Brand new Cat.
Rebuilt smog pump by B-Z rebuilders in California.
All brand new vacuum hoses that are presumably hooked up right. (i'm in the midst of policing my work right now)
ABV works according to tests in FSM. Also inlet hose to smog pump has suction, and the bypass hose is not blowing any air out back into the air filter.
Brand new plugs, distributor cap and wires.
Timing set to 10* with the vacuum hoses unplugged. HAC works to bring the timing up to 16* when plugged in.
Idle mixture screw set using highest Vacuum with idle speed screw set to about 450-500 rpm. About 18 inches.
No vacuum leaks, my vacuum gauge shows 18 inches steady at an idle of 650-700 rpm. This is at 6500 ft elevation.
Choke shows fully open when hot.
Brand new air filter.
Oil has only the mileage on it since rebuild.
New rear brakes might be dragging a bit, just installed new shoes and drums.
Stock size jets.
Fuel in Carb is a little bit higher than the middle of the sight glass during idle.
H55f, so a five speed for the emissions test.
All I've found so far is that the vacuum hoses to the HAC, the ones that go to the Upper Left and Upper right were reversed. I know that this could cause a rich condition, but i'm almost 3 times over the limit, so I'm not sure this will solve it. The CO on the speed graph is high at speed not at idle, so i'm also not sure changing the idle mixture screw to lean it out some more will help.
I'm about to take it for the 3rd test after I switch the HAC vacuum hoses. If it fails then I guess I'll throw some E85 in it? Thanks for all the help on here!
Chad
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