hatchsub Posted January 1, 2006 Share Posted January 1, 2006 Ok i know ive said this before but now im home and actually ready to do the swap from carter-weber one barrel to hitachi 2-barrel. I have a few vacuum hookup questions however. 1.Could someone tell me where the vacuum secondary line hooks up? Im assuming right now that any source of vacuum off the manifold will be acceptable but i want to know where it was hooked from the factory. Seems that every vacuum diagram picture ive looked at shows the drivers side of the carb which doesnt do me any good. 2.Another question I have, since ive decided to not bother using the steal vacuum lines that run under the intake, is can i hook the vacuum advance to both vacuum hookups on the front of the carb. Mr Carb told me he hooked his advance to the lower of the two hookups but im wondering if it would make sense to hook it to both with a Y fitting. Any opinions on this one or am i over thinking this thing? I just dont want to mess up my daily driver. Thanks again guys. Ill take pics during the work and post them for your viewing pleasure..that is when i get down to pulling it all apart. Link to comment Share on other sites More sharing options...
hatchsub Posted January 2, 2006 Author Share Posted January 2, 2006 bump...really need some help guys. Link to comment Share on other sites More sharing options...
Skip Posted January 2, 2006 Share Posted January 2, 2006 hatchsub, 1) The secondary throttle plate vacuum supply on a HiCrappy two barrel is internal. Could you possibly be referring to the choke pull off ? Here is a scan from the 83 FSM 2) The vacuum advance to the distributor can be connected to either one of the "ported vacuum " fittings on the base of the carb. Plug the other. You will be bypassing a thermo control. switch Scan Please to save bandwith please email me if you need other scans Link to comment Share on other sites More sharing options...
wintersubaru Posted January 2, 2006 Share Posted January 2, 2006 If you look under the choke on the front of the carb there is a vacumm port there. I run mine with three lines, one to disty one for heat and one for brake booster. The one i have hooked to the disty is a port that dose not get vacuum untill the primary opens thus pulling open disty advance. I have been running like that for a year now and every thing works fine. The one i use is just above the idle screw. Link to comment Share on other sites More sharing options...
hatchsub Posted January 3, 2006 Author Share Posted January 3, 2006 I believe mine is an earlier carb than yours wintersubaru. I only have 2 vacuum lines on the front of my carb. I do remember having something like 3 or 4 on my 86 EA81 carb though. Link to comment Share on other sites More sharing options...
wintersubaru Posted January 3, 2006 Share Posted January 3, 2006 I believe mine is an earlier carb than yours wintersubaru. I only have 2 vacuum lines on the front of my carb. I do remember having something like 3 or 4 on my 86 EA81 carb though. What year car did the carb come from? i have an 86 ea82 and allso have looked at other years and they all have that port. If not try one of those other two. You will know if it works if when you step on the gas every thing revs up right. If not it will hesate real bad untill you get the rpms up. Would help if you had a pic of your carb. Link to comment Share on other sites More sharing options...
hatchsub Posted January 3, 2006 Author Share Posted January 3, 2006 well took some more close looks at the carb today. The line that i thought was for the vacuum secondary def is. If i open the vacuum secondary and hold my face near the vacuum port i get a blast of air coming out. Only problem is i would think if i opened the secondary and held my finger over the port that the secondary would stay open but it doesnt. Is something wrong here or does it just need more vacuum than a finger over the hole to keep the secondary open? I dont want to put this thing on and find that i only have a single barrel carb again. And Wintersubaru, 75subie sold me the carb and i was told its off an 82 or 83 EA81. Its been rebuilt and has something like 5000 on it. Link to comment Share on other sites More sharing options...
wintersubaru Posted January 3, 2006 Share Posted January 3, 2006 well took some more close looks at the carb today. The line that i thought was for the vacuum secondary def is. If i open the vacuum secondary and hold my face near the vacuum port i get a blast of air coming out. Only problem is i would think if i opened the secondary and held my finger over the port that the secondary would stay open but it doesnt. Is something wrong here or does it just need more vacuum than a finger over the hole to keep the secondary open? I dont want to put this thing on and find that i only have a single barrel carb again. And Wintersubaru, 75subie sold me the carb and i was told its off an 82 or 83 EA81. Its been rebuilt and has something like 5000 on it.The year diff means our carbs r different. Sorry i couldnt be more help.Ever think of getting a weber? I got lucky and someone gave me a re built holley weber 5200, Had to make my own linkage because it opens the other way then my hitachi but im sure it will work got adapter plate today so when the weather breaks i will put it on and start tuning. good thing is i have a extra intake so i can get everything bolted down on the bench.(A.K.A kitchen table). Anyone else hear run the holley weber? If so how does it perform Link to comment Share on other sites More sharing options...
hatchsub Posted January 3, 2006 Author Share Posted January 3, 2006 No prob wintersubaru. Anyone else know where to hook up the vacuum line for the secondary? Can i just hook it up to a vacuum source on the intake manifold...maybe the same one as the choke pull off? Link to comment Share on other sites More sharing options...
wintersubaru Posted January 4, 2006 Share Posted January 4, 2006 No prob wintersubaru. Anyone else know where to hook up the vacuum line for the secondary? Can i just hook it up to a vacuum source on the intake manifold...maybe the same one as the choke pull off? I dont know a lot about carbs but i am pretty sure you have to have the vacuum for disty advance above the throttle plates so its not pulling all the time. I tried hooking mine up to intake like you said but my car ran like crap. I didn't know at the time it was my problem i thought it was a bad carb because it would run ok if i wired the choke closed a little. Thats when i did some research and found out it can not be a constant pull. So i hooked it up like the diagram in this post says and my car ran great. That carb should have a vacuum port above the throttle plates some where. If i knew how to make pics smaller i have some from my hitachi and i could show you where i have mine. pm me with an email adress and i will send them to you. Link to comment Share on other sites More sharing options...
hatchsub Posted January 4, 2006 Author Share Posted January 4, 2006 Thanks Wintersubaru but i think i understand where to hook up the dis advance. The only problem im having is that i have a vacuum hookup coming out of my secondary diaphragm and i dont know where to hook that up. I would think it would be ok to just hook to the same source of vacuum as my choke pulloff but im not sure on that. Link to comment Share on other sites More sharing options...
wintersubaru Posted January 4, 2006 Share Posted January 4, 2006 Thanks Wintersubaru but i think i understand where to hook up the dis advance. The only problem im having is that i have a vacuum hookup coming out of my secondary diaphragm and i dont know where to hook that up. I would think it would be ok to just hook to the same source of vacuum as my choke pulloff but im not sure on that. Dont know if this will help but mine is hooked to a port above the throttle plates. Link to comment Share on other sites More sharing options...
hatchsub Posted January 5, 2006 Author Share Posted January 5, 2006 An update now. I had a local shop put a vacuum gauge on the secondary hookup that im talking about and the secondary didnt open. They suspected the diaphragm was busted so i went home and opened it up and pulled out the diaphragm. It looked fine to me but i went down to napa and placed an order for a new one anyways. When i got back home something still wasnt sitting right with me cause that diaphragm that i pulled out looked brand new. It was still plyable and everything. So i went and looked at the plate that i removed to get to the diaphragm and bingo..figured it out. It IS internal vacuum! There are two openings on the cover...one to the inside of the carb and the other to hook up a line and run to where ever its supposed to run. Cant get my money back on the diaphragm that i ordered but its probably just as well cause i dont want to put it back together and have the chance of leaks now that i pulled it apart. Still dont know where to hook that external vacuum line for the secondary though..Anyone? Link to comment Share on other sites More sharing options...
hatchsub Posted January 7, 2006 Author Share Posted January 7, 2006 Ok got some time to work on it yesterday. I have all the bolts for the intake out and everything that needs to be unplugged, unplugged. There are only two things keeping me from taking it out. The Steel EGR pipe with the fitting going into the block is still connected and the steel pipe that hooks to the coolant hose coming out of the firewall is still hooked. Am i going to have problems with the EGR pipe fitting being seized with time? Im not really worried about getting the hose off the coolant pipe its just being a PITA and i was tired by the time i got to it and decided to call it a night. Also there is another electrical device that i found while taking stuff apart. It mounts on the drivers side intake bolt and has two vacuum lines coming out of the bottom of it. Its about an one inch by one inch barrel shaped thing. Is this important? If so im going to have to figure out where to hook those vacuum lines when i finish converting to hitachi. Thanks everyones for your help this far. Link to comment Share on other sites More sharing options...
wintersubaru Posted January 8, 2006 Share Posted January 8, 2006 Ok got some time to work on it yesterday. I have all the bolts for the intake out and everything that needs to be unplugged, unplugged. There are only two things keeping me from taking it out. The Steel EGR pipe with the fitting going into the block is still connected and the steel pipe that hooks to the coolant hose coming out of the firewall is still hooked. Am i going to have problems with the EGR pipe fitting being seized with time? Im not really worried about getting the hose off the coolant pipe its just being a PITA and i was tired by the time i got to it and decided to call it a night. Also there is another electrical device that i found while taking stuff apart. It mounts on the drivers side intake bolt and has two vacuum lines coming out of the bottom of it. Its about an one inch by one inch barrel shaped thing. Is this important? If so im going to have to figure out where to hook those vacuum lines when i finish converting to hitachi. Thanks everyones for your help this far. I can help with the EGR pipe but not the device. For the EGR, soak the heck out of it overnight and try to remove it from the head with a line wrench allso soak the bolts that hold it to intake incase it won't come out of the head. When i did mine i snaped a bolt on the intake and found it easer to get it out of the head. Since i don't have emissions i put a plate over the intake side and pluged the hole in the head with a threaded plug. But if you have emissions i wouldnt do that. Link to comment Share on other sites More sharing options...
hatchsub Posted January 10, 2006 Author Share Posted January 10, 2006 Hey thanks wintersubaru. I took your advise and soaked the hell out of the bolt on the head. I tried to get it free a few times last night to no avail but this morning i went out there and put a set of vise grips on it tight and hit the vise grips with a hammer and it broke free. Got the entire intake out of the car now. I even got one of the intake gaskets stuck to the manifold so one less i have to scrap off the head. The rest of my work today involved sorting out the vacuum mess under the hood. The vacuum lines are very similar when you sit down and look at them next to eachother (that is the carter weber lines compared to the hitachi). I already have the vacuum lines all squared away..just a matter of waiting for my secondary diaphragm to come in from NAPA to put everything back together. Thanks again. Ill post some picks up when i get a chance. Link to comment Share on other sites More sharing options...
wintersubaru Posted January 10, 2006 Share Posted January 10, 2006 Hey thanks wintersubaru. I took your advise and soaked the hell out of the bolt on the head. I tried to get it free a few times last night to no avail but this morning i went out there and put a set of vise grips on it tight and hit the vise grips with a hammer and it broke free. Got the entire intake out of the car now. I even got one of the intake gaskets stuck to the manifold so one less i have to scrap off the head. The rest of my work today involved sorting out the vacuum mess under the hood. The vacuum lines are very similar when you sit down and look at them next to eachother (that is the carter weber lines compared to the hitachi). I already have the vacuum lines all squared away..just a matter of waiting for my secondary diaphragm to come in from NAPA to put everything back together. Thanks again. Ill post some picks up when i get a chance. Glad i could help! you will notice a big diff in it. I know because last year i had to switch to a carter weber from a ea81 because i couldnt afford an Ea82 carb at the time so i got the ea81 intake and all off a car that was sitting in the back of the repair shop i worked at. It sucked but at least it kept the car on the road. 2 months later got a used ea82 carb (hicrappy) and put it on ran good for long time and does now but it likes to mess up when ever it feels like it so im allmost ready to put my free rebuilt holley weber. Got it mounted to intake just need warm day to put it on. Link to comment Share on other sites More sharing options...
hatchsub Posted January 11, 2006 Author Share Posted January 11, 2006 Ok well got some more time to work on it. Bolted the carb down to the manifold and the EGR valve as well. I sorted out the vacuum mess and cleaned the heads real good. Took a long..long...long time to get all the gasket removed. Got it mounted on the engine, with the help of a buddy to hold the wires and such out of the way as i dropped it in, and torqued down to specs. Basically everything is hooked up except the throttle cable (too short for the hitachi..need a new one) and the alternator. My back was killing me from spending all day hunched under the hood (im 6'2"), so i gave up for tonight. So hopefully ill get it all running good tomorrow. Im just praying it starts up and runs good. Wish me luck guys!! Almost forgot..since i torqued the intake down to 16ft pounds do i need to retorque it down the road or am i all set? Link to comment Share on other sites More sharing options...
hatchsub Posted January 11, 2006 Author Share Posted January 11, 2006 Ok all i got it running. Seems to run really good actually. I had to reseal the thermostat housing and still might end up doing it again..not sure if its leaking or not cause it leaked so much the first time. Oh well. Thanks for all your help guys. Link to comment Share on other sites More sharing options...
wintersubaru Posted January 11, 2006 Share Posted January 11, 2006 Ok all i got it running. Seems to run really good actually. I had to reseal the thermostat housing and still might end up doing it again..not sure if its leaking or not cause it leaked so much the first time. Oh well. Thanks for all your help guys.WoooHoooo!!!! Another sube back on the road! Hows it go down the road? Do you have better power? good luck with the reseal on thermostat. Dont be afraid to use a little sillycone. I like the copper stuff myself. Link to comment Share on other sites More sharing options...
hatchsub Posted February 7, 2006 Author Share Posted February 7, 2006 hey all. Sorry to leave you hanging for so long. Ive been real busy. I ended up putting the car into the shop to button up the details. I needed a new ASV valve put in anyways so it was worth it. They changed out the throttle cable, got the thermostat housing to seal correctly (somehow the bolts that i had were too long for the housing), and replaced said ASV valve and silencer. So anyways knowing my luck it always comes out of the shop with one more problem then it started with. I had an giant exhaust leak from the manifold gaskets. Also all of a sudden my front brakes were making all sorts of noise. I decided to screw it and drive it back to UCONN like that but when i got here i couldnt stand it. So i went and got the exhaust fixed by a shop that knows what there doing. They fixed it the right way with helicoils on the drivers side and the passenger side just needed new studs. No more leaks and its quieter than ever. They also replaced my front pads. Any longer and i would have needed new rotors. Its not that i couldnt have done any of this myself but i just dont have the time and would also rather leave it to people that have done it before. Now for the driving impressions. The car once warm has no hessitation in the throttle what so ever!!! I dont know that it has any more power than the one barrel off idle but it continues to make power up to 4500 rpms where the one barrel would cut my engine off at around 3500. I still havent really tuned the carb so i might be able to pull a bit more out of it later on. During the swap however i lost my tranny kickdown. Im thinking the manifold i have is off a manual subaru because it doesnt have any place for the kickdown to mount as far as i can see. Oh well just means that i have to manually downshift it to second when i need to and over this summer swap the tranny to a 5 speed. I also now have the ECS light coming on because i didnt put the duty solenoid back on the manifold simply because i didnt have one. Runs great without it though. Thanks everyone for your help on my project. It would have been nice if i could have avoided putting it into the shop twice but i just ran out of time and had bad luck with other things going wrong. Link to comment Share on other sites More sharing options...
rubuild Posted February 8, 2006 Share Posted February 8, 2006 The reason your having trouble with vacuum circuits, is due to the carb your using being an 81 only carb. Subarus first attempt at ecm control. They s***canned it right away. The vacuum port on your secondary housing was used to pull off the secondarys in a fast decel so your throttle would not stick wide open. I will try to attach 3 vacuum schematics for 81, they might help, however you would be better off with a federal carb. from an 84 if you could find one. Kerry/Roo-Builders Files are to large E-mail me if you like rubuild@aol.com Link to comment Share on other sites More sharing options...
hatchsub Posted February 8, 2006 Author Share Posted February 8, 2006 I really dont think there is a problem with my secondary. It opens under full acceleration but i dont have a lot of power low down when its only the primary which leads me to believe i need to fuss around with the mixture a bit. All in all im happy with how it performs compared to before and im also all set for when/if i decide to upgrade to a weber. Link to comment Share on other sites More sharing options...
Myrdynn Posted February 28, 2006 Share Posted February 28, 2006 high, I have an 87 soob gl hatchback with high-low 4WD and a four speed tranny. I am installing a carb from a 1981 soob. I was hoping that I might get you to send me scans of the carburetor so that I don't adjust the wrong screws. thank for any help you can give; Rev. Matthew Link to comment Share on other sites More sharing options...
GeneralDisorder Posted February 28, 2006 Share Posted February 28, 2006 high,I have an 87 soob gl hatchback with high-low 4WD and a four speed tranny. I am installing a carb from a 1981 soob. I was hoping that I might get you to send me scans of the carburetor so that I don't adjust the wrong screws. thank for any help you can give; Rev. Matthew Well - as for adjustment, there shouldn't be any. Just the idle speed adjustment. The mixture on the Hitachi is controlled by jets that are not adjustable. There is an idle mixture adjustment screw as well, but it will be blocked with a roll-pin preventing adjustment as it is set from the factory where it needs to be. Just start it, and set the idle speed to about 700 - 800 RPM. GD Link to comment Share on other sites More sharing options...
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