andrsn Posted January 24, 2016 Share Posted January 24, 2016 I'm trying to get my 227k mile Brat legally on the road here in Portland Oregon but it won't pass DEQ. I rebuilt the carb a couple months back and the car starts and runs great; pulls plenty strong, rev's well and hold a nice idle right around 800rpm's. To sum up my experiences: Trip 1 - failed putting out 2200ppm hydrocarbons (unburnt fuel), adjusted carb. much more carefully via air mixture screw Trip 2 - no air coming out of tailpipe caused by huge hole in muffler, replaced muffler with a Magnaflow (not sure how they got a reading the first time but whatever...) Trip 2 - failed putting out 580ppm hydrocarbons, replaced plugs and leaned out the mixture as much as possible without the mixture screw falling out Trip 3 - failed putting out around 600ppm hydrocarbons I have noticed that once the car is running i can unscrew the air mixture screw as much as i want without actually removing it and the engine doesn't seem to be affected, that seems odd. I did notice that the fuel level in the sight is on the high side, could that have anything to do with it? The car definitely needs the mixture screw in the correct position (about 4 turns out from closed) to start but once started it doesn't seem to matter... What should I try next? I would like to do an ej swap in the next 2yrs. so I'd prefer not to spend a ton of $$$ on a weber, cat etc... if I can avoid it. I gotta get this sweet ride back on the pavement! Quote Link to comment Share on other sites More sharing options...
turbosubarubrat Posted January 24, 2016 Share Posted January 24, 2016 Have you tried running it on the high way at high rpms (like 5k) so the cat heats up and clears out for about 15-20 minutes? Quote Link to comment Share on other sites More sharing options...
hatchsub Posted January 24, 2016 Share Posted January 24, 2016 Have you tried running it on the high way at high rpms (like 5k) so the cat heats up and clears out for about 15-20 minutes? This^ My gf had a car that would fail because she refused to run it on the highway. It was only failing by a few points too.... 1 Quote Link to comment Share on other sites More sharing options...
skishop69 Posted January 24, 2016 Share Posted January 24, 2016 Something is not adding up with your methods. The mixture screw adjusts the amount of fuel at idle, not air. Backing it out will enrich the mixture, not lean it out. Ideal setting is 2-3 turns out from being lightly bottomed to start. If you can back it out all the way with no runnability issues, something is wrong inside the carb. Are you certain you got the primary and secondary jets back in the right spots? You can switch them and it will cause a serious rich issue. An issue with the airbleed jets can cause this too. The level in the sight glass should be at the half way mark, no higher than 2/3, IIRC. Are all the vacuum lines hooked up correctly? EGR not stuck partially open or leaking? PCV system working correctly? 1 Quote Link to comment Share on other sites More sharing options...
andrsn Posted January 25, 2016 Author Share Posted January 25, 2016 I have been taking the scenic route to the DEQ, but that is still only about 15mins. Next time I go I'll drive it a bit longer/harder. I guess my understanding of the mixture screw was a bit backwards, I'll reset it to 2-3 turns out from bottomed (but it seems start idling the smoothest around 4 turns out). I'll take the carb off to check my jets, blow out the passage ways again and lower the float level. I've started looking at my vacuum lines and they seem to all be in order, I'll take a look at the EGR and PCV stuff too. thanks for the tips i'll let ya' know what happens... Quote Link to comment Share on other sites More sharing options...
andrsn Posted January 25, 2016 Author Share Posted January 25, 2016 Something is not adding up with your methods. The mixture screw adjusts the amount of fuel at idle, not air. Backing it out will enrich the mixture, not lean it out. Ideal setting is 2-3 turns out from being lightly bottomed to start. If you can back it out all the way with no runnability issues, something is wrong inside the carb. Are you certain you got the primary and secondary jets back in the right spots? You can switch them and it will cause a serious rich issue. An issue with the airbleed jets can cause this too. The level in the sight glass should be at the half way mark, no higher than 2/3, IIRC. Are all the vacuum lines hooked up correctly? EGR not stuck partially open or leaking? PCV system working correctly? Are the EGR/PCV parts the same for my ea81 engine as they are for an ea82? There's a parts car down the street from me and I'm planning on buying what appears to be the weber carb from the owner, I'll grab that stuff too if its compatible. thanks. Quote Link to comment Share on other sites More sharing options...
turbosubarubrat Posted January 25, 2016 Share Posted January 25, 2016 Yes on both the egr and pvc. I ideally you would get a egr with 1 port for a weber swap, but if you get a 2 port cap off the big port. Your pvc and egr are probably working fine but it would still be a good idea to take them off and clean them. Quote Link to comment Share on other sites More sharing options...
ferox Posted January 25, 2016 Share Posted January 25, 2016 Set your idle mixture screw between 2-2.5 turns out from lightly bottomed. Check to make sure your timing is set at 8 degrees BTDC. Then use the air/fuel mixture screw (different from the idle mixture screw) to set the rpm. Check timing again to make sure it's still at 8. Then begin lean-best-idle tuning. If the idle mix screw is not making a difference in the way the engine runs, that means you are bypassing the idle circuit, which is the main metering circuit for your carb. This can be because the circuit passages are clogged and the carb will only run by bypassing it, or other specs of the carb were adjusted from stock location such as the fast idle screw (which should not be adjusted unless you really know what you are doing). Both situations seem to be common. 1 Quote Link to comment Share on other sites More sharing options...
andrsn Posted January 26, 2016 Author Share Posted January 26, 2016 Set your idle mixture screw between 2-2.5 turns out from lightly bottomed. Check to make sure your timing is set at 8 degrees BTDC. Then use the air/fuel mixture screw (different from the idle mixture screw) to set the rpm. Check timing again to make sure it's still at 8. Then begin lean-best-idle tuning. If the idle mix screw is not making a difference in the way the engine runs, that means you are bypassing the idle circuit, which is the main metering circuit for your carb. This can be because the circuit passages are clogged and the carb will only run by bypassing it, or other specs of the carb were adjusted from stock location such as the fast idle screw (which should not be adjusted unless you really know what you are doing). Both situations seem to be common. Now I'm slightly confused, as far as i've seen there are 2 adjustment screws on the exterior of the carb. The idle mixture screw is the screw at the front base of the carb (this is what i have been starting with at 2-2.5 turns out from bottomed, but i seem to need to go further than that to get it to start and doesn't seem to have any effect on things between 3ish turns out until its completely removed)? The the air/fuel mixture screw is the one attached to the throttle cable bracket (I've always referred to that as the idle adj. screw and it definitely changes things)? Where is the fast idle screw? Either way, i'm gonna remove the carb, adjust fuel float level, blow out he passage ways and re-install as well as clean or replace the pcv and egr stuff. I'm going to buy the weber from down the street too, maybe i should just focus on installing that... Quote Link to comment Share on other sites More sharing options...
andrsn Posted January 26, 2016 Author Share Posted January 26, 2016 Got home and cleaned my pcv valve, it only has about 3/8" movement I'm hoping that seems about right. A small amount of oil also came out of the spigot at the top of the valve, maybe someone put in too much oil at some point in time (that happened to one of my motorcycles once)? My EGR valve was incredibly dirty inside. When gently pushing air in/out of the top spigot on this noting was moving anywhere, not sure if that seems right.. I could hear the diaphragm inhaling/exhaling as i used a bicycle pump to push air in/out of it. I glanced at my carb while i was out there, the fuel level is actually right in the center but it hasn't been driven in a day. Also here is a shot of my carb from my rebuild but i can't tell if i got the jets in the correct spots as Skishop69 was mentioning Quote Link to comment Share on other sites More sharing options...
turbosubarubrat Posted January 26, 2016 Share Posted January 26, 2016 That top pic is the egr. Pvc looks like this. Have no idea what the middle thing is supposed to be called but i know it is apart of the exhaust recirculation system / emissions stuff that i always delete. Quote Link to comment Share on other sites More sharing options...
ferox Posted January 26, 2016 Share Posted January 26, 2016 turbosubarubrat mentions a good point, your problem may not lie in the carb, but all the out-dated and defunct emissions parts that should be removed. Quote Link to comment Share on other sites More sharing options...
andrsn Posted January 26, 2016 Author Share Posted January 26, 2016 turbosubarubrat mentions a good point, your problem may not lie in the carb, but all the out-dated and defunct emissions parts that should be removed. That's definitely a possibility, I was pretty careful when rebuilding the carb. and when I put new spark plugs in, the old ones looked nice and tan without any signs of running rich. Quote Link to comment Share on other sites More sharing options...
andrsn Posted January 27, 2016 Author Share Posted January 27, 2016 Well, the Weber carb. didn't work out. I'm gonna clean the pvc tomorrow and give it a longer drive before deq this weekend, I'll also try leaning out the carb by turning the screw in the correct direction this time... Can anyone tell me what emissions stuff I can remove and still theoretically pass DEQ? If that stuff is causing more harm than good when trying to pass I'd like to get it out of the equation. Quote Link to comment Share on other sites More sharing options...
ferox Posted January 27, 2016 Share Posted January 27, 2016 PM sent. You should just stop by my place this weekend, and take a look at my Hatch. I can walk you through anything that isn't obvious. Quote Link to comment Share on other sites More sharing options...
Rust Posted January 27, 2016 Share Posted January 27, 2016 just run it on denatured alcohol when you show up for the test. Quote Link to comment Share on other sites More sharing options...
joe5 Posted January 28, 2016 Share Posted January 28, 2016 I'm surprised that you even have to pass deq with your brat. Isn't old enough to be exempt? Quote Link to comment Share on other sites More sharing options...
turbosubarubrat Posted January 29, 2016 Share Posted January 29, 2016 For portland vehicles 75 and newer have to be deq'd unless except like heavy diesels. Quote Link to comment Share on other sites More sharing options...
joe5 Posted January 29, 2016 Share Posted January 29, 2016 ah gotcha. OP: u should email VW headquarters for some creative suggestions 2 Quote Link to comment Share on other sites More sharing options...
jonas Posted January 29, 2016 Share Posted January 29, 2016 ah gotcha. OP: u should email VW headquarters for some creative suggestions Heh... Quote Link to comment Share on other sites More sharing options...
zeb1234 Posted February 3, 2016 Share Posted February 3, 2016 in the stste of ut, 85 or older you can register vintage. now you can only drive to car shows wink wink but no more safety emissions. 85 gl its tough on old drivers maybe check into it Quote Link to comment Share on other sites More sharing options...
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