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ok so i got a guy to fix the timing on my engine and it now runs 

but now where trying to tune it and its to hard with the stock carburetor

so I'm gonna get the weber one 

does anyone have any tips on how to install it or things to look out for 

i already know about the tie down bolt may be to high and i might have to grind it down 

but do you guys suggest anything else 

 

also here's the carb I'm getting 

https://www.morris4x4center.com/weber-carburetor-38mm-dges-2-5l-or-2-8l-k490.html

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It’s pretty simple. The instructions are on line if you look for it. Not much to them as I remember.

 

Far as tuning it except for idle speed there’s not much to do, I’d leave the mixture alone. It’s a damn good carb out of the box

 

If you get stuck I can get pictures of how i routed the vacuum line and ran power sources.

 

For tuning Problem you’re going to have is if the distributor is being advanced correctly by the computer, if it works. Vacuum advance would be better in this set up but I never read anything about nor converting a California emission to this kind of carb.

 

How does it run now?

I have a guess about why you and the previous owner are saying it’s had to tune. But what it it doing that makes it hard tune?

 

 

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what i ment was we are trying to tune the idle speed but can't get this carb to work the way we want 

so I'm gonna put the new carb on and hope fully it will be nice and easy 

also i like this new carb because i can put a vacuum controlled distributor on it and get rid of my computer thats 

controlling the current distributor 

 

yes can you post some pics of how it looks 

 

if i get this distributor 

http://www.rockauto.com/en/moreinfo.php?pk=1123678&cc=1181393&jsn=395

then will it simply work by plugging it into the ignition coil and then connecting a vacuum hose to it

do you know how its suppose to be hooked up 

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Ok that is the correct looking distributor however the part description is for without vacuum advance or centrifugal advance.

 

Big thing to look for is sourcing a new distributor is the wire and plug that go from the distributor to the ignition coil, I needed to find a new one because the previous owner butchered the wiring,

Had to buy a used distributor to get that wire and plug in one piece. All the rebuilt ones didn’t some with it and the only replacements I could find were for the electronic advance like you have now.

 

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A1 Cardon part # 301630 & ac delco 88864745 are the correct one, maybe be other 2.8 vacuum advance will work are well.

don’t know why rock auto doesn’t show it for the 1986 Comanche, it does come up for 1985 jeep 2.8.

 

That autoline d2100 looks perfect except for the description it should be what you have already

 

 

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the two that you talked about don't have any wires to connect to the ignition coil 

 

and yes i see what you mean by mine

the picture looks great but the description says its not vacuum advance i will have to call and ask them about it 

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I looked the part up on manufactures website and it looks the same, D2100 interchange is 85-86 only jeep, Chevy, olds, Pontiac, Buick , 2.8 carbureted , 4 terminal module, without EST system

Which is correct for a non California 2.8 jeep.

 

I think rock auto had the wrong parts description. If you get one and it is correct with the wire to the ignition coil I may buy one just for that damn wire, it’s 85-86 gm carbureted vehicles only so far I can’t find a replacement part #..

Before 1984 Chevy had a different flat spade terminal ignition coil. Which rockauto also list incorrectly for autoline parts (D2081 82-84 gm), so I think rockauto listed the interchange wrong for most of this companies parts.

 

 

 

 

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ok got the new carb in havent had time to install it yet 

mostly because I'm not sure exactly how to hook it up 

and i really don't get why the hoses are pre cut, why can't it just be one long hose that i cut myself 

and also why does the hose not even say "fuel line" or "fuel safe" do they want me to assume that its safe for gas with no label  ???

 

16jj39c.jpg

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That's fuel line. 

Typically, with a carb you'll have a mechanical fuel pump on the engine. Somewhere between the carb and pump you'll install a fuel filter. Weber is insuring that you don't run a line from the carb to pump without the filter, hence, two hoses. 

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It may be fuel line after all, I thought the kit included a vacuum line splitter but it was decades ago when I first installed it.

First pictures are coming up, its kind of hard to see what's what so I am breaking it up into sections then using a paint program to make the lines more visible. Often I have to go back and retake a photo because the mess of vacuum lines its unclear when the line goes.

 

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Distributor is up first. Tracing back from the distributor vacuum advance it goes along the back of the engine to a metal Vacuum line which take it from the front to the engine when it goes to the only vacuum port on the front of the Weber 38 DGES carb.

(Images were saved as lower resolution so they could be uploaded.)

distributor GM vaccum line1.jpg

distributor GM vaccum line2.jpg

distributor GM vaccum line3.jpg

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I believe the distributor line is correct because it is similar to how it runs on the factory vacuum diagram except it looks like it cut out a few superfluous connections that are no longer need with the weber carb.

 

Next is the diver side valve cover PCV to Carb, a lot of those metal lines run to a canister at the front near the radiator. I could stand to clean it up a little better, the plug is blocking a line the OEM carb used, probably should eliminate the need for that.

Crap looks like I'll hit the limit on file size soon

 

 

GM PCV line to Weber Carb.jpg

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Never mind! Refreshed the page and I could upload again. :)

Brake booster line (in red) is on its own originating from the back of the intake manifold below the where the Vacuum line spilt in to a tee at the top.

Off the tee split the line (in green) split again for the vacuum going to the CAD actuator, main line then continues to vacuum canisters on the passengers side engine bay fender.

On the canister the line marked with yellow goes to the dash heater controls, line marked in purple goes to a vacuum switch at the front of the intake ---which I'll post next.

84 to 86 GM engine brake booster.jpg

GM Vac Tee 84-86.jpg

84 to86 GM Vacuum Canaster.jpg

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Last vacuum line to trace (marked in pink) originates at the tee at the back of the intake goes around to the vacuum switch in the front of the intake, second port from the top, which splits up again.

The line mark with purple splits off the last port of the vacuum switch going all the way back to the vacuum canister on the fender.

I am certain the vacuum routing can be cleaned up a lot more, not being the first owner I'm not 100% certain these vacuum lines at the switch  are the way it should be, however it runs right, Vacuum CAD axel works well, and the dash vacuum control has always worked well too.

84 to 86  GM vac line to vac intake switch.jpg

84 to 86  GM vac line to vac intake switch2.jpg

84 to 86  GM vac line to vac intake switch3.jpg

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Last but not least for powering the electric choke, on the 1986 harness I found a new way, where the engine harness ran along the firewall I found a plug that only power on with the key, so I located a plug to match it then ran the power side to the terminal on the electric choke. The line that is hot with the ignition on is the one with that stupid twist on wire connector (BTW previous owner of the donor jeep the harness came from put that connector on)

 

On my original harness I used on of the other wires that came on with ignition, just kept testing until I found one, may have even been the original power line to the OEM GM carb's choke. You've probably got all kinds of connectors and power sources to choose form with the California emissions harness. Didn't cover the fuel line because you should have more or less already run that with getting the pressure regulator set up.

1986 Weber Choke power source.jpg

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AMCKID,

 

You now have an old-school Weber. 

 

You need-

 

One vac line from the carb base to the dist. 

One throttle link.

One wire to choke. 

One fuel line. 

 

That is it. 

 

Vac lines-

One line from intake to PB booster. 

One line from intake to blend door.

 

 

 

As for both of you-

 

In FL you have no emissions. 

From what I can find, you only have emissions in Phoenix and Tuscon, if you don't live there...........all the mess needs to go. 

If either of you are have troubles with engine performance.............it's the cluster posted above. 

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