Jump to content
Ultimate Subaru Message Board

Simplifying the EA82 Hitachi hose nightmare


Recommended Posts

I'm trying to simplify the vacuum hose setup in my 1991 EA82 L Series - along the lines of what is suggested in this 2008 thread. Trouble is i've tried to follow the suggestions but can't easily relate them to my current setup (for instance - I don't seem to have an EGR, just a hose running from the spot where it should be to an Anti-Backfire Valve).

 

I've photographed my engine bay and labeled as many parts as I can find based on the schematic and pictures that is in my manual for my model car. I've followed all of the hoses and they seem to be pretty consistent with the schematic.

 

Can anyone help with what I could remove in my case to make the whole thing as simple as possible?

 

2hzjxnq.jpg

 

dr71oy.jpg

 

jztonp.jpg

Edited by fishboy
Link to comment
Share on other sites

I did not post earlier hoping someone that works on ea82s would chime in, but the diagram is reminiscent of an '84 ea81. I work on ea81s so full disclosure, but going from the diagram I am fairly confident you can remove:

 

Silencer

Reed Valve

Air Control Valve

Vacuum Valve

Anti-Backfire valve

Thermal vacuum valve

Hot Idle Compensator

 

 

If you live in a warm part of the country you can remove the air cleaner vacuum motor vacuum line. The "motor" just directs pre-heated air drawn over the exhaust pipe into the intake during start-up. If you don't have a foil pre-heater hose connected to the exhaust and air cleaner, then it does nothing anyway.

 

You should be able to remove the Bowl Vent Solenoid and connect the bowl vent hose to the charcoal canister. You can probably leave the in-line check valve if you want.

 

On the diagram, if any of the lines you are keeping have an R on them that means they have an orifice restrictor in them. They are a small brass pellet with a tiny hole in the middle. You will want to make sure you keep them and re-install them when you replace hoses.

 

After you do all this you will have to re-adjust the carb for sure, and if it's a feedback system then it might take some adjusting, then driving, and adjusting some more until you find the sweet spot. On feedback ea81s we just remove the computer. I am not sure if Aussie ea82s have a more integrated computer, so hopefully someone else can advise on that one.

Link to comment
Share on other sites

Somehow I Found Amazing that no one has suggested yet, that the only REAL way to Simplify a Hitachi Carbureted EA82 Engine is to Remove that Hitachi Crap and install there a 32/36 Weber Carb.

So, the only vacuum Hoses that Should Remain will be Three:


  • The Vacuum Advance to the Distribuitor.
  • The Vacuum accumulator bottle (For A/C Buttons and Push-Button 4WD).
  • The Brake Booster Vacuum.

Look my Weber Writeup, ~► Here.

But if you Still want to keep the Craptachi carb, you must Turn the Secondary Stage of that carb to Mechanic
(See

about that) and cap almost every port... and Still it will not work very properly...

Good Luck!
Kind Regards.

► Edit: Updated to update the Web Link on the Word: "Here" 

Edited by Loyale 2.7 Turbo
  • Like 1
Link to comment
Share on other sites

 

But if you Still want to keep the Craptachi carb, you must Turn the Secondary Stage of that carb to Mechanic and cap almost every port... and Still it will not work very properly...

 

Good Luck!

Kind Regards.

 

I beg to differ. Hitachi 28/32 converted to mechanical secondary. No Vac lines. Works beautifully. I haven't touched it since installing!

IMG_1137.jpgIMG_1138.jpg

  • Like 1
Link to comment
Share on other sites

Yes, I Agree but Let me Explain Why I Wrote that it will not work Properly: I meant it due to emmissions Stuff and the EGR still Hooked; also if that is a Feedback carb... issues related to Smog stuff.

 

But I Agree that a Mechanical converted Hitachi Carb works Way Better, because it opens when you Press the Pedal, (when you Need it) not depending on Vacuum and RPM's.

 

Kind Regards.

Link to comment
Share on other sites

I Used to Run my EA82 BumbleBeast with its original Hitachi Carburetor, Mechanical Converted, you can Look how it Works on the Followin' Video:

 

 

 

 

But even Like That, it Doesn't compare with the Performance + Simplicity Gain with the Weber Carb.

 

 

http://www.ultimatesubaru.org/forum/member.php?tab=visitor_messaging&u=17344&page=3#visitor_messaging

 

 

Kind Regards.

Link to comment
Share on other sites

Not very Dificult, but you must be Creative to use a Hard metallic Wire attached to the Primary Stage Mechanism, and you must be Patient enough to do the Proper adjustment to make it Hook and Hold the Secondary in order to open it when the Primary has reached the Half opening.

 

Also you must adjust it to let it Fully Open the Secondary when the Primary is Fully Open, not Before.

 

And you Must Remove the old Vacuum Actuator Hardware for the Secondary.

 

If you cannot do that or does not have enough experience with Carburetors, I Kindly suggest you to take it to a Profesional Shop and let 'em do the Mechanical Conversion for You.

 

You'll avoid Headaches.

 

Kind Regards.

Link to comment
Share on other sites

Gotta love those Japanese engineers. Vacuum everything! :lol: What a mess!

 

I'm not much help but you do appear to have a loose hose on the upper left corner of the pic.

 

 

You should see a Honda CVCC it is even worse. From these years most cars are a vacume line nightmare.

Link to comment
Share on other sites

I did find this writeup here:

 

Ok, to start I can't find any pics of an EA 82 to show you, and I sold my GL wagon in the spring, so I don't have the car to use as a reference. I also tend to makeup names for things when I don't know what they are called, but I'll try and be as descriptive as possible.

Things you'll need:

1 gallon anti-freeze

1 set intake gaskets

Deluxe multi pack of vacuum plugs

2 3in x 3in x1/8 in pieces of aluminum

1 3in 10mm length of allthread

1 can or tube of RTV

3 pennies

1 air box top from the J.Y.

1 plastic elbow plumbing fitting from the hardware store

1 12pack of Old Style or some other cheap beer

Black Sabbath Volume 4 (you can sub with any early Sabbath album)

 

Now I'm assuming that the car has a Hitachi carb and is non AC. Also you may want to remove the alternator to give you more room.

Crank up the Sabbath!

Jack the car up, block the wheels, etc, etc. Take off the air box and disconnect all the lines and hoses, chuck that but keep the top part and wing nuts.

Next disconnect the fuel lines, master cylinder vac line, the heat selector vac line, the chock/vent solenoid wire connecter from the carb, upper radiator hose, throttle cable, along with the temp gauge and oil gauge wires (and anything else that connects to the intake).

Unplug all of the wires going to the little emission solenoids.

 

Now you can start tearing all the lines off, remove all the 3 million brackets and vac lines from the hard lines on and around the intake, dump the vapor canister vac booster, all that crap!

 

Ok, from under the car at the exhaust manifold you'll see a hard line coming off right above the exhaust pipe on each side, I call these the sideburns, I'm not sure what they are really called but it doesn't matter because they're history! Unbolt them but save the bolts and the gaskets (I think there's gaskets, I can't remember), you'll need them later.

 

Now pull the intake manifold, and remove all of the hard lines, I think it's like two or three bolts.

 

Pull the rest of the sideburns out from above, and whatever is left. This is a good time to plug the heads clean the block, I like to use oven cleaner.

 

Crack your first beer.

 

Once you've got everything cleaned up and the hard lines off of the intake, bolt that bad boy back on with the new gaskets.

 

Using the aluminum plates, fab up cover plates for the holes where the sideburns came off, and bolt them on.

 

Crack second beer.

 

Reconnect the master cylinder vac line, and fuel lines. Connect the vacuum advance on the distributor to any vac port on the manifold. Do the same with the heat selector vac line.

 

Run a hose from the driver side rocker cover to the PCV.

 

Plug all of the ports on the carb except the vent solenoid valve. On my EA 81's I run the large port on the back of the carb to the manifold. I don't think I did it on the EA 82, but you might try it.

 

Plug the EGR valve on the back of the intake. I've also removed the EGR on mine and made a cover plate for it. Seemed to work well.

 

Reconnect the radiator hose, gauge wires, choke wires, and throttle cable.

 

Start it up! If it starts and won't idle or idles ruff, check that all the manifold ports are plugged. If it idles but stutters or stalls when you whack the throttle, check the ports on the carb. Pump the brakes to make sure your getting vacuum boost works. Turn on the heater to be sure you have vacuum to the selector. Check for exhaust leaks at the sideburn caps. Readjust the idle and fuel mixture accordingly. Top off the coolant.

 

Crack your third beer.

 

For the air cleaner, or air box as I like to call it, take the lid from the J.Y. and cut a

2 3/8in diameter hole in the center (the outer diameter of the mouth of the carb). Using the RTV glue a penny over the hole on the right side (looking at it from above and reading SUBARU left to right). Hog out the left hole and install the elbow fitting, this will allow you to run a hose from the bottom of your air cleaner to the passenger side rocker cover. This will be the bottom plate of the air box.

On the other lid, glue pennies over the left and right holes, leaving to center one open. Remove the center bolt from the carb, and replace with the allthread, you might need to put a lock nut on it to hold it down on the carb. Place the bottom plate on the carb, connect a hose from the elbow piece to the pass side rocker cover, put on stock air cleaner, place lid on top, and using Subaru factory wing nut, tighten into place.

 

 

Thats all I can remember, but I'm sure I'm missing some thing!

Hope this helps ( and makes sense!)

 

Any comments on the above?

 

I can follow most of what is said but have a couple of questions:

 

1. The "air box top from the J.Y." - What is this? Is he talking about getting another air cleaner assembly and if so what kind...from an earlier model subaru? Why can't I just use the exisiting air cleaner and plug up some ports or something?

 

2. In this case does the Hitachi carb still use a vacuum secondary or is it implied that he has converted to a mechanical secondary?

Link to comment
Share on other sites

honestly the only way to simplify that vacum mess is to just switch to a weber. i have a craptachi right now and im converting here soon. otherwise dont worry about it.

 

 

mmm..... with the above post i wonder where the 4-12 beers went? ha ha :brow:

Link to comment
Share on other sites

  • 2 years later...

Thanks loyale 2.7 turbo

 

You're Welcome:) 

 

 

Answering your Questions: to be Honest, you must be Aware about how are the Legal Regulations in your Area, Regarding Pollution Control, because if your Subie does Not need to pass emmissions nor having certain pollution control stuff attached, then you can feel Free to do the Weber Swap, and get rid of lots of Stuff, clearing the Engine Bay and turning your subie onto a more reliable Machine, while getting more juice from your Carburated EA engine...

 

Otherwise, if the Pollution and Emmissions control laws are strict in your area, you can not do the Weber Swap easily... But you can improve the response of the Craptachi carb, by doing the Mechanical Conversion.

 

Kind Regards.

Link to comment
Share on other sites

the vacuum secondaries are internal to the carb (mostly, I believe there might be a small canister on the side of the carb) so you can remove the emissions stuff without messing with it.  tbh if your going to tackle this project leave the secondaries for after you are rid of the hoses and tuned to run well.  you will have a hard enough time tuning it in without added complication from the secondaries.

 

I have done 2 following this guide and the other couple on here, and this is what I have found while doing it.  

 

check your throttle shaft play first.  with the car off slightly open the throttle and see if there is any side to side play in the shaft.  its ok to hear a small tick/tick since it will always have some play, but if you can see or hear excessive movement then the carb is pretty much shot and probably not worth the effort unless you just want to learn something about it.

 

don't pull the manifold unless you want to for looks,  you can unhook everything and remove 99% without taking it off, its just some hard metal vac lines that need the manifold removed and they don't hurt anything and aren't really in the way.  snapped manifold bolts are a very common issue and its just cosmetic to remove the metal lines.  you could even saw off the ends to get them more out of the way.

 

plug all the ports in the carb but the large front port that goes to the emissions canister.  that one needs to be open but restricted.  its called a bowl vent, and it maintains proper pressure in the bowl so that theres not vacuum or pressure where its not supposed to be.  it cant be left completely open or plugged.  it has to be restricted a proper amount.  i crammed a hose on it that was a size or 2 small, and left the hose about 2'-3' long and that seemed to get it in the ballpark, so I ran mine that way for a long time.  whatever way you chose this will be an important step.

 

I recommend putting an inline fuel pressure gauge by the carb.  it helps diagnostics a ton and you will want one if you ever do a weber swap.

Link to comment
Share on other sites

Right on fellas, thanks for the info! Luckily I have no emission laws around here to speak of so I'm going with the above quote on removing the vac line mess. The carburetor is still in good shape so I'm going for it, shelling did you leave the too small bowl vent hose 2-3 feet long or 2-3 inches long? And thanks for the advice on waiting to do the secondary conversion!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...