Sapper 157 Posted June 21, 2015 Share Posted June 21, 2015 Okay guys, here's the scoop: I got my carb put back together just the way it was before but with a new accelerator pump arm (old one was bent). Got it put back together, and deleted the emissions that TheLoyal and 2.7 Turbo recommended http://www.ultimatesubaru.org/forum/topic/148041-ea81-hitachi-carb-looking-for-pictures-of-read-to-find-out-p/ Unfortunately, the idle has been whacking out (it dies unless I help it when its cold) and the high idle and secondary still doesn't seem to work! Everything is the same as when it was working properly on the carburetor except the emissions deleting. So I'm wondering if the deleting I did may have actually been harmful?? Its an 84 carburetor so there are several differences compared previous carburetors. So any insight guys? Pictures of your compete hitachis would help me put the emissions tubes back on and see if that helps... but is there anything else im not thinking of? thanks guys. Link to comment Share on other sites More sharing options...
ihscout54 Posted June 22, 2015 Share Posted June 22, 2015 The cold idle problem is very likely an adjustment of the choke system, or a vac leak. How do you know your secondary isnt opening? If you have removed the hoses and plugged the lines to those three ports in the second picture (with blue caps) you may not like the results after the car warms up. Ive mentioned this befor in one of your posts, those ports most likely need to be "opened". The front one is the slow air bleed. The middle is and atmospheric vent for the float chamber. The rear one is the high speed air bleed. There are a series of vac tubes in this system that worm around and are temp controlled. In those tubes are special orifices that control/regulate the air flow to these ports. If you havent thrown these lines away you can look inside them and see what Im talking about. IIRC my setup ran best with the system thinned out and the temp control left in place. The rear most tube (high speed) ran best with the smallest brass orifice. After the control valve it found its way to the air cleaner. The middle (bowl) just goes to its little vac controlled air filter. The front (low speed) used one of the aluminum larger orifice lines and ends at the air cleaner as well. I actually think I have pics on my phone and may be willing to post them If you really need them. Link to comment Share on other sites More sharing options...
ihscout54 Posted June 22, 2015 Share Posted June 22, 2015 (edited) This is a tube with an orifice installed. Those ports I mentioned really need to be open with these vac lines installed. The carb wont run right and will be pig rich with them simply plugged. Edited June 22, 2015 by ihscout54 Link to comment Share on other sites More sharing options...
ihscout54 Posted June 22, 2015 Share Posted June 22, 2015 This is the mess Im talking about. Its a confusing spaghetti pile. I took out the tees and ran the lines with the orifices directly to the control valve and then to the air cleaner. The control valve is actuated by manifold vacuum that is regulated by a thermo valve. I tested the vcv with my vac pump and tested the thermostatic valve with a torch. They both checked out so I kept them. I will post more info on this when Im home if anyone is actally interested. 1 Link to comment Share on other sites More sharing options...
Sapper 157 Posted June 23, 2015 Author Share Posted June 23, 2015 Yes Please keep the info coming!! That spaghetti mess is exactly why I cant figure out which tubes go where. Your info thus far has been very helpful ihscout! Link to comment Share on other sites More sharing options...
ihscout54 Posted June 23, 2015 Share Posted June 23, 2015 I have to do a fuel pump this evening. Im working on a mini writeup that I will post about this separate from your thread, so as not to muddy it up. I havent flaked... 1 Link to comment Share on other sites More sharing options...
djellum Posted June 24, 2015 Share Posted June 24, 2015 the main one is the bowl vent. without a good proper balance it wont run right. I ran with the metering ports plugged, and open and it didnt change signifigantly, but nothing worked right till the bowl vent was right. it needs some restriction but has to allow for air to flow. what worked for me was a line that was too smal crammed on it, and left about 3ft long. i only ran it a few months like that till I got my weber in, but give it a try, only costs $2 in vacuum hose. the only thing hooked to my hitachi was the bowl vent hose and the fuel line (plus return line). all other ports were plugged ran well, not as good as a full set up or a webber, but make 27 mpg highway so I could commute with it. may give you a starting point 1 Link to comment Share on other sites More sharing options...
Sapper 157 Posted June 24, 2015 Author Share Posted June 24, 2015 I have to do a fuel pump this evening. Im working on a mini writeup that I will post about this separate from your thread, so as not to muddy it up. I havent flaked... Thank you, thank you, thank you!!! the main one is the bowl vent. without a good proper balance it wont run right. I ran with the metering ports plugged, and open and it didnt change signifigantly, but nothing worked right till the bowl vent was right. it needs some restriction but has to allow for air to flow. what worked for me was a line that was too smal crammed on it, and left about 3ft long. i only ran it a few months like that till I got my weber in, but give it a try, only costs $2 in vacuum hose. the only thing hooked to my hitachi was the bowl vent hose and the fuel line (plus return line). all other ports were plugged ran well, not as good as a full set up or a webber, but make 27 mpg highway so I could commute with it. may give you a starting point Thanks for the extra input. Right now even though my car is not idling right I'm getting 29 mpg. Link to comment Share on other sites More sharing options...
ihscout54 Posted June 24, 2015 Share Posted June 24, 2015 Have you figured out your secondary Issue? Its not real easy to tell if they work sitting in the driveway. The info I gave will have no bearing on this issue. You have a linkage issue, the diaphragm is shot, the gasket is bad or the theres a restriction in vacuum supply. Link to comment Share on other sites More sharing options...
Sapper 157 Posted June 25, 2015 Author Share Posted June 25, 2015 (edited) I hooked up all the lines where I thought they went. But now my carburetor is running even worse. It's almost like it's running really really rich, it will run in a higher RPM for a for a few seconds, and then it'll start to die, and then the choke will engage and it will bring it back up to 2000 RPMs. Here are a few pics can you spot anything that's out of place? Edited January 18, 2017 by Sapper 157 Link to comment Share on other sites More sharing options...
ihscout54 Posted June 25, 2015 Share Posted June 25, 2015 http://www.ultimatesubaru.org/forum/topic/154295-just-plug-it-taking-some-of-the-mystery-out-of-your-hitachi/ Link to comment Share on other sites More sharing options...
djellum Posted June 26, 2015 Share Posted June 26, 2015 (edited) heres a link you may find interesting. http://www.ultimatesubaru.org/forum/topic/127365-simplifying-the-ea82-hitachi-hose-nightmare/ it deals with EA82 and not EA81's, but a lot of the emmissions reduction stuff will be the same. also the carbs have most of the same ports, they are just moved around a little. might just find that gem in there somewhere. i notice in one of your pics that there is still an open line, what is it for? couple of things from doing the delete I did (full delete, only 3 vacuum lines remaining). gas tank hoses - make sure the input for fuel and return line are correct. make sure that the tank vent tube is not blocked or plugged into vacuum, it needs to be open to air (or charcoal canister if you have one). the big one is that bowl vent. the vent controls the pressure in your fuel bowl, and it needs to have the right pressure in there or you will never get it to tune even remotely well. the choke shouldnt engage unless its cold, id just unplug it till you get it running correct, then worry about it after. theres no real reason for increased mileage from eliminating the parts of the hitachi that make it run well. there should technically only be lossed efficiency, my guess is that the secondaries are not working or your running terribly lean which is not good overall for the motor. cant remember exactly but I think the secondaries are vacuum operated, but the passages are internal to the carb. not real sure about that last bit so double check. strange question, but did you adjust the mixture? its adjustment can be hidden behind a roll pin on the EA82's and you cant see it. if you mess with the carb lines and remove items you will need to readjust. all those hoses arent emmissions related they are what the carburetors uses to run the car. theres very little actual emmisions stuff on these, pretty much just the cat and the ASV system. the rest is actual neccesary parts to running the car and deleting things will not gain any performance increases above stock. now the reason we delete things is when they fail and are too much work or cost to replace. we can get 80% performance with 30% of the hassle and we settle for that until we can get a better solution (true fix or a weber). Edited June 26, 2015 by djellum Link to comment Share on other sites More sharing options...
ferox Posted June 26, 2015 Share Posted June 26, 2015 Looks like you still have way too much useless stuff in your engine bay. Don't use the steel lines under the manifold. Hook your vac lines straight to whatever component they go to. I run the charcoal canister. The only reason not to, is if the vacuum valve on the canister itself is degraded and you don't want to but another canister...doesn't have to be a direct replacement. I'm using one for a Jeep $30 Rockauto. You have the ported vac nipple for the canister/egr hooked to the steel transfer line that runs under the manifold. Is it connected to the canister? If you're not using it, cap it at the carb with vinyl caps. If you are, run a direct connection. You can't diagnose a problem like this with so many unknowns in your connections and obsolete components. Here are my pics again, but maybe use them to see what's not there Link to comment Share on other sites More sharing options...
Sapper 157 Posted June 26, 2015 Author Share Posted June 26, 2015 heres a link you may find interesting. http://www.ultimatesubaru.org/forum/topic/127365-simplifying-the-ea82-hitachi-hose-nightmare/ it deals with EA82 and not EA81's, but a lot of the emmissions reduction stuff will be the same. also the carbs have most of the same ports, they are just moved around a little. might just find that gem in there somewhere. i notice in one of your pics that there is still an open line, what is it for? couple of things from doing the delete I did (full delete, only 3 vacuum lines remaining). gas tank hoses - make sure the input for fuel and return line are correct. make sure that the tank vent tube is not blocked or plugged into vacuum, it needs to be open to air (or charcoal canister if you have one). the big one is that bowl vent. the vent controls the pressure in your fuel bowl, and it needs to have the right pressure in there or you will never get it to tune even remotely well. the choke shouldnt engage unless its cold, id just unplug it till you get it running correct, then worry about it after. theres no real reason for increased mileage from eliminating the parts of the hitachi that make it run well. there should technically only be lossed efficiency, my guess is that the secondaries are not working or your running terribly lean which is not good overall for the motor. cant remember exactly but I think the secondaries are vacuum operated, but the passages are internal to the carb. not real sure about that last bit so double check. strange question, but did you adjust the mixture? its adjustment can be hidden behind a roll pin on the EA82's and you cant see it. if you mess with the carb lines and remove items you will need to readjust. all those hoses arent emmissions related they are what the carburetors uses to run the car. theres very little actual emmisions stuff on these, pretty much just the cat and the ASV system. the rest is actual neccesary parts to running the car and deleting things will not gain any performance increases above stock. now the reason we delete things is when they fail and are too much work or cost to replace. we can get 80% performance with 30% of the hassle and we settle for that until we can get a better solution (true fix or a weber). The only things I tried to plug were the high speed air passage, low spd air passage, and the atmospheric bowl vent. All of them are now plugged in (All thanks to ihscout54's simplified diagrams) and hopefully I did it right. I plugged them all in last night and fired it up and it seemed to run just fine. Are you referring to the second picture? That hose plugs into my air box and I believe it is part of the PCV system. Yeah I have been fiddling with the idle mixture screw. trying to find a sweet spot Link to comment Share on other sites More sharing options...
djellum Posted June 27, 2015 Share Posted June 27, 2015 the bowl vent cant be plugged, or left completely open. webers have an actual atmospheric bowl, hitachis had a solenoid or valve that vented the bowl to the canister. they cant regulate the pressure on their own like a weber can. you need to orifice the bowl vent line, which is a fancy word for have it open to air, but restricted the right amount. since your experimenting you may want to find out exactly what the bowl vent solenoid did and see if it can be mimic'd, fixed, etc. having gutted 2 hitachis and ran a couple webers as well, I would say to find a way to keep the bowl vent setup in stock working order or find a way to mimic it. im not 100% sure that much goes wrong with the Bowl vent hardware, since it ussually gets yanked with the rest of it. in case you may have a couple of dollars to throw at the experiment, you may want to invest in some small valves. hook the valves to the end of the hoses so you can adjust the amount of air that gets in while its running and see what the motor does. make sure to keep your idle low while adjusting the mix. the if you let the idle get too high it can skew the results of what your adjusting. Link to comment Share on other sites More sharing options...
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