distributor timing on 87 carbed ea-82

[djellum]

Hey,

 

just bought a subaru, runs well but afterfires when shifting pretty good. right now I'm just checking for vacuum leaks and such to try to find the issue. I put a timing light on it, and it is set to the very last mark (farthest one clockwise) so I am wondering if its too far out of spec. theres no numbers, just the hatch marks.

 

Anyone know what the last mark would be in degrees? and/or what the proper setting is for it.

 

I want to start with basic tune up stuff before I start troubleshooting too far. theres also a lot of loose vacuum fittings to deal with as well that could be causing problems.

 

any other advise is welcome as well.

[Loyale 2.7 Turbo]

Look under the Open Hood, there should be a Couple of Stickers, one with a Vacuum Hoses' Diagram and the Other says -Beside other Things- the Proper Timing.

 

Usually, carbureted EA82's should run at 8º +/- 2º and EFi EA82's at 20º +/- 2º ... I Run my Weberized EA82 at 20 without problems.

 

There are Numbers but the Timing on your Subie's engine must be out of Spec.

 

Kind Regards.

[mikaleda]

if it is that far off it is probably a vacuum leak. i am not familiar with the ea82 do they have a vacuum operated spark advance? if so that is where i would start. your timing should be somewhere around 8 degrees.

[djellum]

I know there are vacuum leaks. there were 2 or 3 unplugged hoses when i got it home, and plugging them in didn't change anything. there are many hoses that just slide off the peg so they aren't connected well. It is vacuum advance, so I may start there. if its stuck at full advance, or plugged into manifold vacuum it could be screwing with it.

 

I don't have to emission it, so I guess ill just start pulling hoses out. seems the easiest way to eliminate the vacuum problems. once thats done at least ill know it must be a seal or something.

 

is there a certain valve or anything that i shouldn't remove? the carbs supposed to have a vacuum secondary so does it need some of this system to remain to function properly?

[Gloyale]

[

Usually, carbureted EA82's should run at 8º +/- 2º and EFi EA82's at 20º +/- 2º ... I Run my Weberized EA82 at 20 without problems.

 

[/color][/size]

 

87 is the one oddball year of the carbed cars. Only year and model with a single diaphragm Nippon-Denso disty.

 

They changed the disty, but never changed the specs, or the literature to reflect, even in the FSM. They were using up the last of the Carbs and hall effect distys, and so they actually eliminated alot of carb info from the FSM, and what the did leave, they didn't update to reflect the few changes, like the Denso disty, and a couple other vac and vent changes.

 

I truly believe they meant to change the timing spec to 20 deg. with the rest of the SPFI and MPFI cars.

 

I've always found that the 87 cars run better at 20 deg, than the 8 deg. spec. I set up all the 87, Denso disty cars that way and they run way better, no problems with ping or overheat.

 

 

djellum, there should be numbers with those timing marks. The last mark is somewhere around 26 Deg. IIRC

[djellum]

Well I did some stuff today before work. nothing changed but it narrowed it down.

 

I really dont think there is a major vacuum leak. I replaced or trimmed a few hoses, every port is accounted for and is either hooked up or pluged in. I did replace a cracked PCV hose.

 

pulling a manifold vacuum hose would kill the motor as expected, while all the loose connections I found didnt change anything. covering the top of the carb kills the motor as its supposed to.

 

I put new plugs, wires, pcv valve (though the old one seemed to work fine), cap and rotor are new.

 

I still want to check into that timeing issue, if for nothing else to know where I am at. I will check the vac advance unit to make sure its hooked to ported vacuum and generally works right, then see if I can back it up and see some numbers.

[djellum]

well update is that it is running much better, but still causing people to duck when I shift.

 

removed the anti-after fire valve helped it run much better, as well as turned a few screws and replaced a hose or 2. runs good, idles good, has power, good throttle response. just goes off like a shotgun when I shift above 3k.

 

the person i bought it from said they replaced the EGR and it fixed it for a while, but it came back. going to look into the EGR system next, any advise? I can't find any other exhaust leaks that would be providing the air for the after fire, I'm assuming the EGR can do so.

[Quidam]

Hope the EGR work fixes it again.

 

Just some thoughts.

 

Pull a vac on the vac advance can and the carb secondary vac can. They should hold a vac and not bleed off. I've seen several slow leakers that will move, but won't hold a vac.

 

4.5 mm is the size for a lot of the vac lines on your car and it's worth the effort to get that size. Old or larger tubing may not seal properly.

 

I use a hand held vac pump to check these things and it sure makes things easier.

 

hth

 

Doug

[djellum]

seems to respond well to just using a vacuum pump, but Idk if it might be leaking out of the gasket or sometihing else involved. I pulled it last night and made a sheet metal plate to go between the EGR and the manifold so that the ports are blocked. Ill reinstall it tonight and see if it runs better. if it fixes it I will go get a block plate of an EJ car, but for trouble shooting this should have an effect of some sort.

 

Eventually all of it will go away, I am just trying not to introduce more variables than I need to. A webber is the plan, and erasing all the other stuff. Just want to drive it a while and see whats needed before I dump all my budget into other things.

[djellum]

turned out to be the ASV silencers (think thats what they are called). the black plastic canisters were leaking. one at least was actually split, but it wasn't till I pulled them both and plugged the holes that it quit completely.

 

not bad, $2.99 for some stout vacuum plugs is a cheap fix. I will eventually remove the whole system or at least take out the metal lines and hammer them shut like is advised in other posts, but for now the vacuum plugs by the bell housing should work.

 

Thanks for all the help though, its running pretty good right now. Some sea foam and some fluid changes in its near future should see me putting some miles on it.

[chaseman]

So did this fix the exhaust gunshot when you shift? Mine's an 86 carb'd GL and in an earlier post I read that the single vacuum advance dizzy is unique to 87? Mine only has the one vacuum port dizzy too.

[Quidam]

So did this fix the exhaust gunshot when you shift? Mine's an 86 carb'd GL and in an earlier post I read that the single vacuum advance dizzy is unique to 87? Mine only has the one vacuum port dizzy too.

 

Hi,

 

Gloyale was refurring to the Nippon Denso dizzy. On that one if you look inside, parts of it will be blue in color. The end of the coil may even be blue in color.

 

If you look at your coil and it has green dots on it, that's Hitachi. This is an '86 carb Hitachi Distributor.

 

This one has the vac can that is easily adjustable. Screw clockwise for less advance, counter clockwise for more.

 

Hope that makes sense.

 

Doug

[chaseman]

oh thanks dude! This makes complete sense and I wasn't aware of the adjustable vacuum advance. I like the idea of having that extra adjustment available to me.

[djellum]

yes it fixed the gunshot. I removed the rubber hoses and plastic canisters that sit behind the intake, and plugged off the units by the bell housing with large vacuum plugs (as well as the air cleaner ports). this is the mod that people talk about putting quarters in the pipes or hammering the pipe shut an inch or so from the exhaust, but it was simpler this way to see if its the problem. I will eliminate the rest of the system later.

 

Basically find out where the exhaust can suck air from and close it off. I started with the AAV, then EGR, Then ASV. looking back on it, I would do the EGR last.

 

the car was running well so I didnt think the timing was an issue, I would look to close off the exhaust leak first, since its a simple thing to pull the parts off and see if it improves. If its running poor or backfiring out the carb thats different though.

[chaseman]

Sweet , thanks for the update. I'll be doing what you did shortly. My car runs awesome apart from causing gunshot reports in my town.

[djellum]

dredging up an older post of mine since I'm working on this again.

 

as stated before its an 87 carbed EA82. I dont actually know which distributor I have but it only has 1 vac can. my coil does have the green dots mentioned above, but the motors been out before I bought it so who knows what parts came from where. is there an easy way to tell a ND single can from a Hitachi one? Also can the adjustable one be made to fit on either of them? I would really like an adjustable can, just in case.

 

Anyways, the car is running well, but I was just curious and checked out the distributor with my timing light a little while ago. the findings were strange.

 

I wanted to know how much mechanical advance was built in, so I dialed up the idle to about 3k with the vac unhooked and checked with the timing light. didnt show any mechanical advance at all. Ive heard on other motors that somewhere in the 2k range the mechanical should be kicking in, but idk about the boxers. how much mechanical advance should I get and at what rpm?

 

I then checked what I got from the vacuum. threw the vac canister onto manifold vacuum to get full out at idle. showed that my vacuum advanced 25 degrees. 25 degrees seems a little high. It wont hold a vacuum so it needs rebuilt anyway, but is this normal for our cars?

 

I am going to send in at least the vac advance to be rebuilt, but I wanted to troubleshoot any issues with the disty so I can send it in if needed as well.