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sleykin
08-06-2010, 02:02 PM
This is my first post, though I have been reading for several days now. I have an 86 LX fed emmisions carbed accord that was running roiugh when I got it. First fix was a valve adjust. That brought compression up to spec and things started looking up. Someone else has been fiddlin with it that shoulda left it be :) I also replaced the vacuum advance and the choke unloader. It now idles correctly and has good high end (above 3k) torque.

My problem now is that it has wimpy low end (have to slip the clutch to go in first) and it starts jerking when going down the road between 2 and 3K and you are just trying to maintain speed. Let up or mash down on the gas and it smoothes out and seems fine. Vacuum guage installed on it for testing show nice vacuum around 19" at idle and steady. WOT^ drops it right down and then it rises back up as the rpms increase. On the street it seems a bit lower than it should be but nothing remarkable.

:banghead:

TIA
Glenn Neff
Medford, OR

Dr_Snooz
08-06-2010, 08:28 PM
Sounds like you got a surprise package. You know, the kind of car you buy and then open it up and SURPRISE!!! I don't know much about carbs but how's the timing look? How long since the last tune up?

InAccordance
08-06-2010, 11:12 PM
step 1 - buy a weber
step 2 - instal weber
step 3 - profit

sleykin
08-07-2010, 09:15 AM
Sounds like you got a surprise package. You know, the kind of car you buy and then open it up and SURPRISE!!! I don't know much about carbs but how's the timing look? How long since the last tune up?

Sorry about that. I replaced plugs wires cap and rotor. Checked cam timing when I did the valve adjust and ignition timing is on the "T" with the hoses pulled and is at about 26* with them both hooked up and full warm engine. Idle is at 750 (MT in neutral) A/C on brings the idle up to almost 1 K.

As to the "suprise", my daughter bought the car for $200 before I saw it and when I pulled the air cleaner and saw the screw holding the choke half shut I knew I was in for it.

As to the webber :) A $600 carb on a $200 car?? I would weld up a new intake for a holly first.

From all the reading I have done it sounds like I need to rebuild the carb. I would like to keep it as stock as possible but as it no longer needs to pass emissions I may have to remove some of them. It is too warm out to get a very long cold run with it but it seems to run better cold.

I have been plugging off different vacuum lines to see if I can isolate the ofending piece but nothing seems to make it change on the vacuum lines so I am left with the carb I guess.

Glenn

Dr_Snooz
08-07-2010, 10:48 AM
Timing should be 4 deg. BTDC with the lines pulled and plugged. If it's not, then you have a deeper ignition issue (possibly due to a vacuum leak). The manual has a thorough timing inspection section that will guide you to the offending part in most cases. There is a USDM manual here (http://www.3geez.com/forum/showthread.php?t=25137)for the 89 Accord. There is also an 86 manual but it is for Russian cars. Maybe it will work for you though.

Given all the modifications done to the carb, you probably do need to rebuild it. Don't expect it to be any fun. Spend some time and familiarize yourself with the site and the depth of knowledge here before you jump in. The guys on this board probably know more about these cars than even Soichiro Honda himself. If they consistently recommend one approach (eg: Weber carb) over all others, it's because that has consistently proven to be the most effective over time.

Good luck.

itzdave
08-07-2010, 11:01 AM
u can find the webers cheaper than 600 as well...
they can be found on craigslist and ebay, just needing the adapter plate.

InAccordance
08-07-2010, 11:06 AM
i paid $87 for the carb
$44 for adapter plate
about 15 bucks for hose, inline filter, clamps, locktite
even full conversion kits are roughly $300

sleykin
08-08-2010, 07:56 AM
I have the Russian book and a chiltons but they are both rather short on info regarding the emissions controls on these cars. I will block off more vacuum lines untill I am sure I have em all eliminated, then pull the lid and look at how badly cruded up it is. I guess I shoulda done more homework before I jumped in here. $50 for the choke unloader and $60 for a vacuum advance and now $70 for a carb kit is making the webbers sound a lot better :)
I would like to maintain the A/C idle circuit and the cruise control, but if I pull everything and then just put back what I need I think it will clean up things nicely.
I must say I am not favorably impressed by hondas right now.

I have a mill and lathe in the shop so I suppose I could bolt on just about any carb with close to the correct size bores.

Thanks for the info. I will post back and let ya know what I come up with.

InAccordance
08-08-2010, 05:59 PM
http://www.3geez.com/forum/showthread.php?t=11067

Dr_Snooz
08-08-2010, 06:53 PM
I'm still not convinced this isn't a timing issue. You're too retarded at the baseline and too advanced at normal. You really need to find out why. You should be at 4 deg. BTDC with the vacuum lines off and 24 deg. BTDC with them on.

If you're serious about fixing it, I'd recommend getting the factory manual. The Honda manual is $44 from helminc.com which is pretty reasonable for a factory manual.

If emissions aren't a concern then you can consider the vacuum removal, Weber swap, etc. I've rebuilt a couple Keihin carbs (not 3g carbs). They are a pain, but it's doable. You can also consider that.

Keep us posted on what you learn.

lostforawhile
08-08-2010, 06:55 PM
I have a good book that is pretty comprehensive on the emissions, pm me the info and I'll try to copy the sections for you, I just have to locate it, I'll send them to you

sleykin
08-09-2010, 07:07 AM
Ok yesterday I pulled the lid off the carb and the gasket survived so I pulled the power valve and the "bleeder tube" and shot everything with carb cleaner. It changed a few things so I am going to go back through all the checks and adjustments again on the timing and carb. I don't think it is a timing issue as it was doing the same thing with no vacuum advance (diaphram was blown) and I have moved the timing all over the place.

Doc Snooze brought up an issue that puzzels me now. My books tell me to run the timing at the white "T" with the hoses off. As far as I can tell that "T" is top dead center? If that "T" is actually 4* then my cam timing would seem to be off as it lines up the cam marks and that "T" perfectly.

The vacuum advance I bought has an adjustable length on the arm so I could change the amount of vacuum advance I get. I will try the 2* and 24* setup you are talking about though it would be nice to find that ref. I ordered a book yesterday so I will wait to see what it sez before I go looking for more info. Thanks for the offer to copy for me :)

One thing about the honda :) I will never bitch about my 86 Porsche's fuel system again! :violin:

sleykin
08-09-2010, 08:00 AM
Quick question..
How many vacuum ports are on the manifold. The diagrams only show 3 but there are a couple of thermal looking things on the backside of the manifold that could either be going into the water jacket on the manifold or they ar thermal vacuum taps of some type.

InAccordance
08-09-2010, 05:35 PM
thermovalves i believe they're called

sleykin
08-10-2010, 07:15 AM
Well I bought a kit and pulled the carb off. Found vacuum line #7 which controls vacuum switch b. Vacuum switch B controlls the fuel cutoof solenoid (as far as I can tell) So confidence is high that I have found one of my main issues. That and I blew a lot of carb cleaner through the primary venturi jet before it started flowing like it should.
These carbs are no big deal inside LOL. I thought it was gonna have a bazillion little check balls and junk in it. They are actually less complicated than an old rochester. All the scary parts are on the outside LOL.

Well back to :banghead:

Will update this evening after I install the refreshed carburator.

Dr_Snooz
08-10-2010, 05:59 PM
T = TDC

Don't waste money on any manual but the one from helminc. Honda wrote it, so get that one. You can use the others for spitballs or something.

sleykin
08-10-2010, 09:21 PM
All back together and running pretty nicely. I even pulled #7 vacuum line and test drove it. The "herky jerky" came back. Idle is a bit rough but steady and solid. I did re check the timing and set it to 4* and 24*. Low end power is acceptable and it drives ok so I am gonna call it fixed and let her drive it till it's broke :)

Dr_Snooz
08-11-2010, 08:02 PM
Nice work! Admit that it was fun to drive. ;)

InAccordance
08-12-2010, 03:42 AM
anything you fix yourself is the best thing to drive imo.

sleykin
08-12-2010, 06:41 AM
For a little 4 door sedan it drives ok :) Nothing compared to the 86 Celica GTS I had and it isn't even in the same universe as the 63 vette in my driveway :cool:
But bang for the buck wise, we have about $500 invested in a nice driver that everything works on except the missing radio, and that is just a matter of picking one out and stufing it in there.
I have been getting greasy for 50+ years now and have had some seriously fun cars and trucks :) The 69 MGB I had in Germany in 71 was a real kick in the pants..especially after I blew up the motor and modified a few things in the base machine shop on the rebuild...

Thanks for the tips and keeping the tech info available. EFI can really spoil a guy LOL