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EA71 experts, what can cause exessive CO2 Emissions?


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Well I had the '78 wagon worked on today at a shop. Had the valves adjusted, the brakes inspected, and an atempt at smogging...

 

Well it all went pretty bad. The valve job didnt help much since something is wrong with the car/emissions/etc. causing extra fuel to get dumped into the motor, which as a result causes CO2 emissions in the 20%+ range... I have no idea if I connected a vacume line wrong, or if something I did with rebuilding the carb went wrong, or if maybe something else I dont know about is bad... I really wish I could pass emissions with a 32/36 DGAV Weber carb or I would get one...

 

The other thing I found out, was the brakes are almost totally shot. Front pads are nearly gone along with the rotors... That will be a pain to fix. The rears need replacing too, which is even more of a pain...

 

Anyway, I'm kinda screwed since now my dad wants me to get rid of the car rather than spend MORE on it...

 

Suggestions? Ideas? Help? :(

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if your getting to much fuel in your car then you might want to check the float bowl level...

 

if i'm not mistaken those carbs used a foam made float for the bowl... they sometimes get heavy and lower down in the bowl... then more gas goes into the bowl and puts an excess amount of gas in the carb...

 

when you rebuilt the carb did you replace the float?

 

i'm having carb troubles myself... i would check the hoses and stuff... if there are any loose ones and stuff it'll mess everything up...

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it might be any of those things... i'd see if i could get my hands on a timing light... check the timing... if all is well there then i'd look into other things...

 

the float is super easy to check... there is a viewing window on the side of the float bowl... then there should be a dot or something on the viewing window and that dot should line up with the fuel level...

 

if it doesn't then i'd open it up and have a look see...

 

also... i tuned my carb while it was hooked up to an exaust machine... makes it a whole lot easier... most school with auto shops have them... i did mine during class... i'm sure a school in your area wouldn't mind you tuning it... let the students watch and help out... pay the teacher a few bucks and off you go...

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Here's some cheap rotors.

 

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1,1&item=7995742564&sspagename=STRK%3AMEWA%3AIT

 

All the other brake parts are pretty inexpensive too.

 

 

As for the carb, you are running rich. The adjustment screw should be no further out than 2 or 2.5 turns from full in tight.

 

Check float level. Tighten all screws on top of carb. The float does not need replaced. I've never had one that got heavy. If it did, you can adjust it up.

 

IMHO, I'd simple get a replacement carb and then later rebuild yours.

 

The rebuild kit is:

CARB REBUILD KIT (BORG WARNER) 10434B

These carbs are really easy to rebuild in an afternoon.

Todd

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On the issue of the CO % being too high.

It has been my experience that a dumping carb (float to high) will cause the HC's (hydrocarbons) to go through the roof.

 

Other evidence of a "dumper" is

a) black smoke out the tail pipe

B) sooty black sparking plugs.

c) A weird gurgling noise heard in the carb throat along with

raw gas appearing on the throttle butterfly when idling.

 

High CO on the other hand can be caused by incomplete combustion of the mixture,

resulting from a weak spark

or ignition timing that is set incorrectly.

 

My 78 EA71 has ignition points - younger guys may have never seen or adjusted these creatures from the old world.

 

They affect both the spark voltage and it's timing.

 

To add: they go closed as the rubbing block wares down. As the go closed, the dwell increases,

the timing retards, and the spark voltage may fall.

All contribute to incomplete combustion of

the air fuel mix - no carb adjustment can correct this correctly.

 

You may want to check the condition and the gap of these oft forgotten and neglected entities.

 

The vacuum advance is to be connected to a point where it gets NO vacuum at idle - i.e. "ported vacuum".

This can also play havoc with the emissions.

 

Pull the line to the outboard side of the advance/retard mechanism on the dist. and see if it's sucking at idle.

 

Shame on me for looking at the simple stuff first as I am a very simple minded guy.

to wit:

Ask me to roll my pant leg up while I was tying my shoe lace, well... I'd fall on me head thinking about it.

 

Good luck, hope this helps and don't forget about the old school "miracles in a can" fix to sneak one over on em.

Might try a search on that one under "can't pass emissions"

 

 

 

PS Just a gentle exclamation...

this crack of your's

"This new Historic forum sucks, all the people from the other forums doesnt seem to get here..."

 

will not garner many friends on this side of the Suby world.

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Is it your CO or CO2 that is too high? One thing that reallly helps on these emissions problems is to post the test results, with limits, for all the tests run, not just the part that fails. The gasses that are measured, RPM's, etc. give a much more complete picture of how the engine is running, and requirements vary by state and/or county.

 

For example, my recent go around on my Legacy http://www.ultimatesubaru.org/forum/showthread.php?t=41006

the high NOx and very low HC and CO were an indication of a lean mixture and/or higher than normal temperature. Up until a couple years ago they did not test for NOx here so the car always passed with flying colors!

 

On your car, if it has points, i would definitely make sure they are adjusted correctly for dwell and timing. use a dwell meter and timing light.

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The place that did the tune up, along with the testing, refused to even complete the test because of the high CO2 (not CO's). So I didnt get a print out. Plus, there is a hole in the muffler that they didnt like either... I'll have to have that fixed.

 

For the timing, rotating the dist. does exactly what when its rotated left or right? I.E. which way advances and which way does the opposite? I havent found a simple statement anywhere saying which is which :P But I have managed to get the timing somewhat close... (Its still about a cm off to the right of the timing mark)

 

Ill check the float now, see whats up with it through the looking glass.

 

As for the Ignition points, what should I work with for those? Just check it for distance or damage, or something else?

 

I did see a segment in the offical Service Manual I have for the car showing how to adjust the Vacume advance. Theres a screw for adjustment, but it seems like the only way to adjust it is by going by sound which is rather interesting.

 

 

Pardon the comment about the new Forum, but Ive been online so long with so many different forums that i've seen what happens to forum topics that are split of from larger topics to know that usually it ends up with a SIGNIFICANT drop in views, which leads to a ghost town of a topic (note how this forum is getting about 3 threads with new responces a day vs. the old forum where theres well over a page a day of threads with new responces...). It makes it very difficult when you are trying to get help about something specific, even though this topic can apply to both forums...

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Well I checked the timing, it seems fine... At idle is very close. The vacume advance seems fine, I adjusted it and it made that noise it makes then adjusted it back to where it doesnt. Also turned the fuel way down...

 

Its spewing smoke when I step on it now, grey smoke. I honestly dont know what to do.

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Ok, I think I found the problem or at least the result of the problem...

 

I went to check the Idle air/fuel screw, and it was way too far up. So I tighted it down all the way then up to the 1.5 rotations as suggested. I ran the car, and it was still rich, so then I tighted it... And tightented it... until it was TOTALLY tighted, and it still ran rather than stalling out... Its obvious that that screw isnt doing what its supposted to be doing or fuel is getting in there from elsewhere...

 

Suggestions? Ideas?

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You say, and may I be so bald as to quote you directly

"Well I checked the timing, it seems fine... "

You did this with an obvious or was it an I guess it's right?

 

 

Kosta, since you have been on so many forums you must be aware of what is called the "search" engine.

 

Yes, it is more work on your part and yes it can prove frustration and yes you are very tired of hearing this

 

But

 

Have you used ours?

 

The new evidence provides an excellent data base for an attempt..

 

Old cars old tricks.

 

There is a product that is called Seafoam.

 

Some passages in you carb may be not passing properly as you suggest,

 

Sorry I missed this was a CA equipped car until the last post, all bets are off in my court.

 

Good luck- you obviously need the help of Kerry from Rubuilders he is the Hicrappy gruru.

 

Please do not ask how to contact him, he works close with Emily.

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Replace the idle screw. They get worn an then are not effective in doing their job!

 

I was amazed at the difference with a new screw.

 

Todd

Thats a good idea, shouldnt be expensive either... Ill give it a shot. I'll pull it out and see if something is wrong with it first...

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Good luck- you obviously need the help of Kerry from Rubuilders he is the Hicrappy gruru.

 

Please do not ask how to contact him, he works close with Emily.

 

I agree with skip. Get ahold of Kerry and have your carb rebuilt. Most likely there is some trouble with it after your rebuild. No offence, but how many carburators have you rebuilt? They arent that simple, and if one tiny piece is out of alignment or not installed correctly you will have a load of problems.

 

As for your ignition timing... you need to make sure your using a timing gun and have it set at factory specs. I believe your timing for the 78 should be around 8 to 10 degree's BTDC. Check the FSM for all the details.

 

And sorry this forum doesnt see as much traffic as the general forum. Feel free to post in there about your car... the EA81 and 71 are near identical, and I believe that hitachi is alot like the hitachi's on the EA81's.

 

-Brian

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Kostamojen

 

BTW, yes I am using a timing gun.

 

 

and you unplugged the timing advance vacuum before you did it??? to properly set the timing you have to unplug it... also have your idle at 900rpm's since it is a cali car...(instead of 850)

 

although with the advance taken off this shouldn't be such a big deal...

 

sorry if this is a duh kinda idea...

 

and getting access to an exaust machine would help a bunch...

 

last... did it fail during the idle test or the driving test???

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ok well here's a great upgrade for these cars, even if they do have the old style electronic disty in them. Go and find an electronic disty from an '83 to newer 2wd EA81 car. Works wonders for improved mileage, and power as well, plus you'll never have to worry about changing the points in it either since well, i doesn't have any. Its a direct bolt in swap. When I first got my '78 Brat, I did a disty swap and rebuilt the carb and I was getting 30mpg out of it.

 

As for the carb, if you need anything in the FSM about them, maybe one of us with an EA71 FSM can scan them up for you. It came in handy so much when I rebuilt my first EA71 carb....

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I dont have a tach (its not installed yet, I just bought it last week) and I wont have acess to any shops since well the car isnt going anywhere other than my backyard anymore until I can get it to at least run close to properly...

 

I just took the Carb off after noticing that the two bolts under the float area were leaking. Theres definatly an issue with the carb, ive eliminated everything else as being a cause (checked vacumes, timing, etc.). I'm contacting Roo builders to see what they say...

 

Ya, I need to go to pick n pull again to look for rear disk brakes and maybe that disty. But I'm not sure I want to spend more money on that til I can get it smoged, because if it wont smog I'm going to have to get rid of it... (I wish it was a 75 or older car or I wouldnt even have to worry about smog...)

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I might have possibly found the exact problem... The idle screw, on the inside of the throttle, theres alot of corrosive wear where the tip comes out into the throttle area. There looks like possibly there is a gap between the needle and that space, which I would think would allow fuel to seep in no matter how the needle is turned. I can try to take a pic...

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