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84-87 Vacuum Diagram


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The engine I'm installing is an EA71 Fat Case. It has the manifold with it. I've bolted on the carb that I took off of the old EA71. I don't have pictures or a diagram showing which ports on the carb are connected to which tubes. I think everything is connected to the manifold, but I'm not completely sure. I know that the Fat Case came from a DL from somewhere between 84 & 87. I'm just hoping someone has a vacuum diagram from one of those vehicles to help me get this right.

 

Thanks,

chris

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Most of the ports can just be left open. Post a picture of the carb and we'll see what we can do for you. Since you are using the carb from an older engine the ports won't even be the same anyway as the newer model carb so the manifold and lines won't be entirely compatible. Most of it you can just ditch and get it to run just fine if you know what the ports are for and how to treat them.

 

And yes - DL's had EA81's just like GL's in those years. 80/81 DL's had the top-mount starter (narrow case) EA71 and then were switched to the EA81 in '82. The only USDM car to use the fat case EA71 was the STD model Hatchback from '82 to '89.

 

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OK. Here's some pics. I'll type my questions below each image:

 

Carb.JPG

 

Here's my carb. There aren't any vacuums hooked up to the Anti-Dieseling switch are there?

 

Brake_Vac.JPG

 

I know this is the power brake booster. I just don't know where it connects. Is it possibly this in the next pic?:

 

Manifold_Vac1.JPG

 

Is this where the brake booster goes? If not, what does?

 

PCV1.JPG

 

I suspect this is PCV. Does it connect to the breather? Is there supposed to be a valve?

 

AC_Vac1.JPG

 

Is this the Air Conditioner idle controller? Again, where does it connect?

 

AC_Vac2.JPG

 

The other end of this one is a little bit hard to see. It turns straight down and connects to the manifold right near the base of the carb.

 

Vac_Adv.JPG

 

I know this is the vacuum advance. I suspect it connects directly to the carb. I just don't know which one.

 

Random_Vac1.JPG

 

This one is the same size as the fuel line. It connects to the group of hard lines.

 

Random_Vac2.JPG

 

Here's the other end of the hard lines. Do they all go to the vacuum canister?

 

Linkage_Vac1.JPG

 

These appear to be connected to the linkage on the other end.

 

Carb_Vac1.JPG

 

OK, here's the ports I found on the carb. You can see all 3 here, but I put in 3 different pics with me identifying each one for clarification. I suspect this is where the timing advance goes.

 

Carb_Vac2.JPG

 

This one is tucked back in there a bit.

 

Carb_Vac3.JPG

 

This one already has a hose on it. I'm wondering if it goes to the breather to open the preheater line.

 

That's all my pics. I think I covered them all. I really appreciate the help. I want to get this right. I would rather not be chasing vacuum problems after we get this thing running.

 

Thank you so much,

chris

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Carb.JPG

 

You need to install an anti-deiseling solenoid in that hole - your carb is missing the solenoid! It's electric - there are no vacuum connections but without the solenoid you have a big open sucking wound on the side of the carb that is open to the idle circuit - without that plugged off it won't idle at all.

 

Brake_Vac.JPG

 

Correct.

 

Manifold_Vac1.JPG

 

Correct - Brake booster vacuum supply.

 

PCV1.JPG

 

Valve cover breather line. Do a search on "PCV* Weber" - that should get you plenty of threads where I've detailed how to handle the PCV routing from both valve covers, the PCV valve, and the air cleaner, etc. You should be able to use those concepts to get a handle on how it works and how to connect it to the stock Hitachi airbox.

 

AC_Vac1.JPG

 

That is the A/C idle up solenoid. When you turn on the A/C it pulls back on that arm and contacts another peice on the throttle cable wheel. It bumps up the idle speed by 200 to 300 RPM or so in order to compensate for the load from the compressor. You don't seem to have the other parts that make it work with the wheel so you'll have to find them or fab something. Not that hard - I made one work with a Weber a few years ago.

 

AC_Vac2.JPG

 

Just a manifold vacuum supply. Cap it if you have no specific use for it at this time. The line comming off the two round choke pull-off pots needs a manifold supply. The one that line is connected to would do......

 

Vac_Adv.JPG

 

Connect the distributor vacuum supply to that lonely vacuum nipple right on the front, bottom of the carb. Down and to the left of the idle cut solenoid port.

 

Random_Vac1.JPG

 

Most likely the float bowl vent line. Your older model carb doesn't have a port for this so remove it. And while you are at it remove that whole hard-line assembly and replace the fuel line with a solid rubber hose - it's probably due for replacement anyway.

 

Random_Vac2.JPG

 

Yeah - trash all that mess.

 

Linkage_Vac1.JPG

 

The top one - not sure. Remove the hose and cap the port. If it runs strange uncap it...... trial and error on that one. The lower one I mentioned above - give it a manifold vacuum supply.

 

Carb_Vac1.JPG

 

Vacuum advance is correct - should be on the lowest one. The middle one is for the EGR valve - just run a new peice of vacuum line back to it. The upper one - another mystery. Cap it - pretty sure you won't be needing it. Some of these ports don't exist on later carbs - that's a good example of one right there and mostly I deal with EA81 carbs from 82 and up personally. But I'm fairly certain you can cap that one and forget about it.

 

Carb_Vac2.JPG

 

Yeah - cap it. No clue - metering port of some kind perhaps.

 

Carb_Vac3.JPG

 

That is the distributor advance - now that I'm seeing all your pics I realize that you have two distributor advance hoses because on the carb it was disconnected at the disty and at the disty it was disconnected at the carb..... lose one of them.

 

GD

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