jacksokm Posted March 16, 2015 Share Posted March 16, 2015 Hi Community, I don't know what to do, I've got an 81 BRAT, went from a Weber back to stock carb. Everything is set up as it should (according to my mechanic in Berkeley CA) and it's not coming close to passing emissions and now has no power after 3,500 RPM. I need an experts help. What could be going wrong. Stranded in San Francisco, Jack jacksokm@usc.edu 510-409-7861 Link to comment Share on other sites More sharing options...
ihscout54 Posted March 17, 2015 Share Posted March 17, 2015 Too help you with this we kinda need to know why you are failing. HC, NOx, CO? Or is it failing the visual exam? Did you get a results printout showing why you didnt pass? Link to comment Share on other sites More sharing options...
jacksokm Posted March 17, 2015 Author Share Posted March 17, 2015 Thanks Subaru Fanatic! It's not failing visual. According to my mechanic it's all set up close to stock as possible, and it's a brand new rebuilt from the manufacturer Hitachi carb. It's failing HC/NOx/CO - not at idle, but at 2,500 RPM it's way over. My mechanic also says that it doesn't have any power after 3000 RPM now - when it had the Weber on it (which I had to take off because it's not legal in CA based on the serial number) it had plenty of power throughout the rev band. Jack Link to comment Share on other sites More sharing options...
ihscout54 Posted March 17, 2015 Share Posted March 17, 2015 Where did you get this "stock carb from"? The hitachis came in a few different calibrations. Couple of theories for you which should occur to your mech as they are not subaru specific. A float setting issue, wrong main jet, maybe egr valve malfunction. Causing excessively lean condition giving high nox. Its also causing a miss giving high hydro readings. Over advanced timing or too much advance from the advance mechanism. Kinda oppisite direction but might make sure the disty and egr system are hooked up to the right vac ports. Hows the evap system? If its wrong its just a vac leak. Pcv the same. These are gizmos that may have been deleted or unhooked while it was weberized. Link to comment Share on other sites More sharing options...
jacksokm Posted March 17, 2015 Author Share Posted March 17, 2015 I got it from National Carburetor. The product number is SUB167 - according to their site it's the stock Hitachi for an 81 BRAT. My mechanic thinks one of the jets may be backwards. The EGR is in and working - in regards to the vac ports I'm not sure. All that stuff was deleted during the Weber conversion, but I sourced all those parts and my Subaru Mechanic of 30 years says we got all the right parts back. He's also saying the carb is wrong and recommending I send it back to the manufacturer - which sucks because it represents another several weeks until I can get this thing out of the shop, and what if the carb is right...? Any way I could get you in touch with my mechanic? Jack Link to comment Share on other sites More sharing options...
ihscout54 Posted March 17, 2015 Share Posted March 17, 2015 Is your mech a member? Keep in mind "new" parts can cause issues. Is the egr oem? Its been a few years since ive opened one of those hitachi monsters. I cannot speak for the rebuilder you bought from but it looks like they have pretty good prices. I have had horrible experiances with rebuilt carbs in general; bad throttle shaft bush jobs, sripped screws/jets, mismatched jets, wrong parts etc. I cannot recall if the jets can even be mixed up on these carbs. Hence I would be of little help to a 30 yr master tech. Ide imagine a busy tech doesnt have time to try to remember this ancient carb crap. As mentioned sounds like he already covered the basics that came to my mind. I will likely not know the specs which I think hes looking for, like what size jets its supposed to have (another member might).... Would it void the warrenty to open er' up? Is it at all possible for you to make the weber look stock? Like modify the origional air filter? sounds like that might have a better chance of passing. If it can pass the visual. Get your money back have a simpler carb and better driver. Link to comment Share on other sites More sharing options...
two85s Posted March 18, 2015 Share Posted March 18, 2015 Hi Jack, I have a post/ thread on here about my CA smog challenges. I'll post a link. I would recommend asking USMB members if they have an extra OEM/ vintage/ used carburator that is the one you need. At least you would be working with the actual original equipment. I hope it works out for you ASAP. CA and the DMV (and the auto industry) want the old cars off the road even if the tail pipe reading are within limits. My mechanic said even a lot of the "newish" cars are failing left and right because the "limits" are constantly changing. Post what you find out. Cheers, Aaron http://www.ultimatesubaru.org/forum/topic/146755-85-gl-wagon-smog-fail/ Link to comment Share on other sites More sharing options...
ihscout54 Posted March 18, 2015 Share Posted March 18, 2015 My heart goes out to you guys on this ca emissions crap. An emissions inspection isnt necessarily a bad thing, but why isnt it good enough for the car to pass a simple visual check (like egr hooked up, evap can inplace, and the gas cap is there and not replaced with a rag or something stupid). Then let the sniffer tell the rest of the story. Its more govt bs creating jobs for someone i suppose. Perhapse they do this to ensure your not just adjusting to pass and then readjusting after the test. You likely wont be passing emissions until the driveabilty issue is corrected. If the egr is not the correct unit it may have too large an orifice and act sorta like a leak. If the lack of power doesnt dissapear at wot, or with the egr disconected. Its probably not that. Another thought for your guy is the power enrichment circuit may not be working on your new carb. Im not clear on how it works. Link to comment Share on other sites More sharing options...
spicypeanut Posted March 18, 2015 Share Posted March 18, 2015 Just to add my .02. I was able to ALMOST get my brat to pass smog with the weber on it. I had all the factory lines routed as if the weber was the factory carb. So the EGR system was working as it was intended to. With that setup, and the timing retarded, it almost passed. Then I added a single catalytic converter to the exhuast and tried again. Passed no problem. 1 Link to comment Share on other sites More sharing options...
ihscout54 Posted March 19, 2015 Share Posted March 19, 2015 Just to add my .02. I was able to ALMOST get my brat to pass smog with the weber on it. I had all the factory lines routed as if the weber was the factory carb. So the EGR system was working as it was intended to. With that setup, and the timing retarded, it almost passed. Then I added a single catalytic converter to the exhuast and tried again. Passed no problem. I proposed this option already but his car is being worked on my a professional. If the tech is even willing to do this it may be cost prohibitive. The fact that you succeeded proves its doable. I think the biggest challenge will be modding the kidney bean airfilter to fit the weber. A hacksaw, some rivets and silicone should help make that weber air cleaner base work with the stock unit. Even if its not daily driver quality use it as the emissions passing filter. Link to comment Share on other sites More sharing options...
spicypeanut Posted March 23, 2015 Share Posted March 23, 2015 I proposed this option already but his car is being worked on my a professional. If the tech is even willing to do this it may be cost prohibitive. The fact that you succeeded proves its doable. I think the biggest challenge will be modding the kidney bean airfilter to fit the weber. A hacksaw, some rivets and silicone should help make that weber air cleaner base work with the stock unit. Even if its not daily driver quality use it as the emissions passing filter. It's funny how you mentioned this. As I actually just did that over the weekend. I wish my camera was working so I could take some photo's of the process. But I can only show you guys the finished product. Link to comment Share on other sites More sharing options...
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