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EA82 carb sticky throttle


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Hello I bought my first subie this fall, an -85 gl sedan, they're starting to get rare here in Norway because they have all rusted away.

Anyways, recently it has developed a problem. When i rev it over 2000 rpm, it stays on 2000rpm for a second or two before it goes down again, the throttle cable is not sticking...

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How many miles on the engine? What engine?

Sounds like there is either a vacuum leak in a hose or around the carburetor.

Or could be the throttle shaft has worn bushings not only making a vacuum leak but also binding up the shaft at a certain point . Spray some carb cleaner around the intake near base of the carb while the engine is running, on the vacuum hoses and where the intake bolts on the heads. If you hear the engine die out while spraying then you have a vacuum leak.

Do it systematically. Spray the carb base first then the hoses and finish up at the intake on the heads.

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check the throttle shaft for movement....

 

i had the throttle on my EA81 carburetor stick wide open due to the throttle shaft getting out of alignment with the hole it sits in

Was it bad bushings around the carb shaft? I fixed mine with an O ring that Wont deteriorate with gas. I took the throttle lever off the carb and put it on the shaft where it meets the carb. That is just a temp fix though.
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I've tried to find a vacuum leak today without luck:( I checked the throttle shaft for ply, but it was not loose, the shaft itself is not sticking, it returns as it should. I've also tried spaying it with carb cleaner to be sure.

 

But the problem seems to be worse now, it can suddenly stay at 2000rpm for a good while, and then return to idle. The problem seems to be worse when the engine has warmed up:-\

 

I have the Haynes repair manual, but it does'nt contain a schematic for the vacuum system for the ea82, I'm shure it has been posted several times here, but I can't fint it. If anyone can provide me a link, it will be much appreciated:D

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Did you spray all the Vac lines. I had one that had a split in it and it wouldn't leak until warm. Also if you can follow the vac line from the carb to the Distributer. Take that vac line off the carb and suck through it. If it sucks air easy then you may have a bad diaphragm in the Disty. Also do that to the EGR valve vac line. Take the air cleaner off and spray carb cleaner around the accelerator pump on the carb as they leak sometimes to.

Are you sure the cable is not binding? Take it off the carb, hold it tight in your hand and have someone push the gas pedal slow to see if you can feel any binding.

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Hello I bought my first subie this fall, an -85 gl sedan, they're starting to get rare here in Norway because they have all rusted away.

Anyways, recently it has developed a problem. When i rev it over 2000 rpm, it stays on 2000rpm for a second or two before it goes down again, the throttle cable is not sticking...

 

The rust thing, relativily low mileage, happens moreso when the engine is at operating temp, throttle cable not sticking...

 

Just a thought, remove the carb from the intake and spray it all down with lubricant. Then work it, lots of linkage for choke and throttle, may be the throttle shafts sticking in the bores..."when hot". Just lube and work it and see if it all frees up for you. Or not:)

 

hth

 

Doug

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I've sprayed alle the vac lines going off the intake and the carb where they connect or split, but i will check them more closely tomorrow, and the other things you mentioned. Thanks for your help!

 

I revved the engine by turning the throttle on the carb, and I could feel that it went all the way back, but it would still stay at 2000rpm for a few seconds.

 

O.T. i found 2 lines plugged with screws going off the front of the carb (towards the rad), they were all rotted, so i changed them, but it didnt do any difference. What did they do?

 

2012-01-29134551400x300.jpg

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Holy Cow!

 

Seems like that Hitachi carb is messed up, because one of those lines belongs to the Secondary Stage actuator (A vacuum on the Carb's Back) and the other goes to the Timing vacuum Advance port on the distribuitor...

 

Are those ports still plugged with Hoses?

 

I Was about to suggest you to install a Return spring on that carb, but by seeing it, could I Ask you why don't you Swap it with a Weber Carb?

 

EA82 engines perform Much Better with them, plus those are very easy to work with.

 

I Have a Complete writeup with pics about that, just Click on my Avatar.

 

Kind Regards.

Edited by Loyale 2.7 Turbo
mispelled word
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The rust thing, relativily low mileage, happens moreso when the engine is at operating temp, throttle cable not sticking...

 

Just a thought, remove the carb from the intake and spray it all down with lubricant. Then work it, lots of linkage for choke and throttle, may be the throttle shafts sticking in the bores..."when hot". Just lube and work it and see if it all frees up for you. Or not:)

 

hth

 

Doug

 

My soob is one of few that is still not rusted around here:) But anyways i have checked the linkages and the all seem fine. But i have a spare carb laying around, so i could swap it if i dont find a vacuum leak.

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Holy Cow!

 

Seems like that Hitachi carb is messed up, because one of those lines belongs to the Secondary Stage actuator (A vacuum on the Carb's Back) and the Timing vacuum Advance port...

Are those ports still plugged with Hoses?

 

I Was about to suggest you to install a Return spring on that carb, but by seeing it, could I Ask you why don't you Swap it with a Weber Carb?

 

EA82 engines perform Much Better with them, plust those are very easy to work with.

 

I Have a Complete writeup with pics about that, just Click on my Avatar.

 

Kind Regards.

 

The timing advance and the other connections on the carb are all connected. I dont remember how, but these 2 lines is the only ones that are plugged.

If anyone could provide me a vacuum line schematic, it will be much appreciated:)

 

I have read your weber swap guide, and I've considered it;)

 

The car ran fine before, i haven't touched the carb setup since i bought it

Edited by Padawan
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Well... if your subie doesn't need to pass smog tests, you can do the Weber Swap and believe me: You'll never go back with an Hitachi carb anymore.

 

The Weber will also allow you to clean the engine bay from the unused stuff... :burnout:

 

...and will add a Loud deep Boxer Rumble Note on the Higher Rpm's, also will add more Low-End Torque.

 

My Brand New Weber came "Made in Spain" so if you live in Norway, I Guess that maybe you could find one easier and cheaper...

 

Good Luck!

Kind Regards.

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Well... if your subie doesn't need to pass smog tests, you can do the Weber Swap and believe me: You'll never go back with an Hitachi carb anymore.

 

The Weber will also allow you to clean the engine bay from the unused stuff... :burnout:

 

...and will add a Loud deep Boxer Rumble Note on the Higher Rpm's, also will add more Low-End Torque.

 

My Brand New Weber came "Made in Spain" so if you live in Norway, I Guess that maybe you could find one easier and cheaper...

 

Good Luck!

Kind Regards.

 

We have strict emissions testing every 2nd year, but since my car doesn't have a catalythic converter, it might pass with a weber.

Weber kits are easy to get here.

 

Pic I took this morning:

2012-01-28144501600x450.jpg

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I think i found the problem:/ The diaphragm in the vac advance was bad. I could suck right through it.

 

Can I plug the output on the carb temporarely the see if it fixed my first problem? ( I will order a new vacuum advance unit of course)

 

But I wonder why the engine accelerated fine w/o vac advance all the time i drove it this way. In my VW bug, the engine woldn't accelerate w/o vacuum advance.

 

I've also taken some pics of the vac hose routing that I will upload as soon as i get home. ( no computer in my garage)

F. ex. the hose to the vac advance is going from the second-from-top outlet on the front end of the carb through a pipe on the underside of the intake. I hope you understood that:D

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I think i found the problem:/ The diaphragm in the vac advance was bad. I could suck right through it.

 

Can I plug the output on the carb temporarely the see if it fixed my first problem? ( I will order a new vacuum advance unit of course)

 

But I wonder why the engine accelerated fine w/o vac advance all the time i drove it this way. In my VW bug, the engine woldn't accelerate w/o vacuum advance.

 

I've also taken some pics of the vac hose routing that I will upload as soon as i get home. ( no computer in my garage)

F. ex. the hose to the vac advance is going from the second-from-top outlet on the front end of the carb through a pipe on the underside of the intake. I hope you understood that:D

 

Yes I do, the pipe has a rubber hose on each end of course one end to the distributor, and the other goes to that bottom metal vaccum line out the front of the carb.

 

Yes, it should run well with even the vac. canister bad, but you just don't have vaccum advance. (Edit and you have a vaccum leak, may be your problem) However it will perform better with a new vaccum can.

 

The advance mechinism inside the distributor may be a little gummed up and sticking, or harder to move than when it was new. But I can't see how that would cause the other problem.

 

Hose hooked to the top nipple is a vent. If you mean the vac hose was hooked to the vaccum port center left of the carb, that one goes to manifold vaccum, and you had a vaccum leak with the diaphram busted.

 

I'll have to think about that though, need to run shortly.

 

hth

 

Doug

 

Gotta go, hope that makes sense:)

Edited by Quidam
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Thanks for your reply!

 

I'm at home now, eating dinner. I took som pics as mentioned, but i see now they're not that good. I'll use my first picture:

 

The top an bottom ones are plugged, the middle one is currently going to the distributor.

I have never done anything to this setup. It ran fine before with this setup too.

 

2012-01-29134551.jpg

 

I'll read myself up a little on the vacuum system components so i can make me more understood:o

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Hey,

 

That center vac port most likely goes to "slots" above the throttle shaft, and having it hooked up to the distributor like it was, would give the correct vac source just like the original bottom vac source.

 

So you're good to go there, either way you hook it up.

 

Doug

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Hey,

 

That center vac port most likely goes to "slots" above the throttle shaft, and having it hooked up to the distributor like it was, would give the correct vac source just like the original bottom vac source.

 

So you're good to go there, either way you hook it up.

 

Doug

 

OK. Thank you :)

 

I found out that I only have a single port vac advance unit. I'm in the process of ordering a new one.

 

But i still haven't found the source of my problem. I have read a little, and it's a few other things i want to check.

 

Getting closer:D

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