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EA81 Vacuum Port Help

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I'm afraid I've messed something up... EA81 Hatch Hitatchi Carb

 

Please answer if you know with Port or Manifold

 

1. Distributor

2. EGR

3. Choke Pull-off Diaphrams

 

 

And then there are some ports on top of the carb, apparently one isn't supposed to be plugged... are there more that aren't actually vacuum?

 

If we identify these from left to right across the picture as 1, 2, and 3, which is what?

 

P1060335.jpg

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1. Ported

 

2. Ported, late

 

3. Manifold

 

As for the other ports, the center one is the bowl vent, and you want to vent that to either a charcoal recepticle, or atmosphere. The other ones are breather tubes of some sort. I'm not sure exactly what purpose they serve.

 

GD

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1. Ported

 

2. Ported, late

 

3. Manifold

 

As for the other ports, the center one is the bowl vent, and you want to vent that to either a charcoal recepticle, or atmosphere. The other ones are breather tubes of some sort. I'm not sure exactly what purpose they serve.

 

GD

Difference between 'ported' and 'ported, late' is,,,?

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Ported is immediately above the primary throttle plate, so it gets vacuum when the throttle is open even slightly. Late ported is higher above the throttle plate, and doesn't see vacuum till the plate opens farther - thus EGR only begins openeing above 1500 to 2000 rpm or so. In practice there's about 1mm difference in the port location above the throttle plate to facilitate this effect.

 

GD

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Those capped "breather tubes" may be for the feedback carb application. Those ticking little solenoids that regulate the amount of air through the emulsion tubes to adjust the fuel mixture ????? I'll look at mine to see, if it hasn't been confirmed in a few days.

That thing in front with the wire on it is the idle stop solenoid ??? Not sure of the name at the moment, but it stops the flow of gas when you turn off the ignition so the engie doesn't diesel or run-on. If you remove it, snip the wire first. If not, you will twist it right off while unscrewing it. Use a butt-connector or small wire nut to get it back together. I've ruined two by not remembering to snip the wire. One I managed to repair. Just to the left of that there are two small vacuum hoses. The left one is for the distributor, the right the egr.

Don't flame me on my spelling, I just spent 14 hours on the road and I'm beat!

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I try very hard not to. I don't want the next owner (if I don't drive it into the ground first) to shake his head and think I'm a complete doltz..... like I find myself doing so often while fixing other people's mistakes and poor maintenance

 

Cutting and splicing takes longer, costs more, and introduces the possibility of corrosion. Taking the wire loose from the plug just makes sense. All you do is insert a awl and bend the little tab that holds the blade into the plastic housing. Slide it out, and unscrew the solenoid.... what's so difficult about that?

 

GD

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as you can see from my picture, it may have already been unscrewed improperly as the wire is hanging on by a thread!

 

Also, I don't think this is a feedback carb as I have no O2 sensor. Am I wrong?

 

Thanks for the advice everyone

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You do not have a feedback system if you don't have an O2 sensor, but they could have used the same carb for both. Or that carb is not original. Since they are capped off, leave them that way. It may be a good way to clean the inside of the carb. Remove the caps and spray carb cleaner in the barbs.

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I just looked at mine, and the plugged ports are for the feedback set up. The one over the left(distributor) vacuum port. And on the back, the one farthest from the choke diaphrams are connected to the solonoids on mine. Just leave them plugged.

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