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Discussion Starter #1
Ive got a pair of ADDHE 40's on my 86 Spider. When I bought the car the carbs. leaked and were terrible so I ordered rebuild kits for them and freshened them up. Ran it Balanced them and all. It ran pretty good, but not perfect. Cyl 2 had a missfire when cold, but when warmed up was fine.

I let the car sit for probably 2 months doing body work and finishing a couple other vehicles. I pulled the choke it spun over a couple times and fired up fine. I let it sit and idle to warm up everything was fine. Got in to move it and any touch of the accelerator it dies out and backfires terribly like its flooding. I tinkered with it for a couple hours and no luck any load on it it would shut off. So next day I pulled the air cleaners and started checking it out. pulled the carb covers adn everything looked ok. fuel level looked good, no trash or anything. So I filed the points and fired it up again. Same deal. This time I watched the carbs with the air cleaners off and noticed it misting some fuel out of the front carb when accelerating. Doesnt seem to have alot of vacuum on cyl 1 but 2 seems ok. I am lost. volume screws are out 2 turns and they have been balanced with tools i have for the webers on my BMW.

Any help would be great!!
 

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check the float level, then the fuel pressure to the carbs..
 

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Discussion Starter #3
I dont have much for specs on these old Solexs. Anyone know what the float measurement should be? Im running the stock electric fuel pump for the bosche Jetronic injection.
 

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thast your problem,:eek::eek::eek::eek::eek:, stock injection pump.. you are blasting fuel to the carb at 45psi.:eek::eek:. you only need 3-4 psi on a carb car.. remove the bosch fi pump, replace it with a 3-6 psi pump and get a regulator.. so you can adjust it to 3-4 psi.:). should not cost more than $50.00 at local autozone.:)
 

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"Points"? Wouldn't expect that on an 86 car. Many other bolt-in options, but this is probably not your problem.

As noted above, totally wrong fuel pump. However, I was suspecting that you had a dead fuel pump rather than over-pressure. It may be that replacing your Bosch fuel-injection in-line pump with a low pressure Facet will cure both problems, if in fact the FI pump was dead.

It is relatively normal to see some misting out the intake of in-line carburetors if you remove the air intake box. There is a bit of reversion during the 4-cycle process, so you'll see some coming out. No worries on that score, really. Of course, a LOT of misting suggests your FI fuel pump was working and totally drowning your car. I'm stumped how you could run carbs with this fuel pump for any time at all, as its pressure should overwhelm the needle and seat and flood everything.

If I read your post right, a previous owner did the conversion. I think there is a fuel return line on an 86 with L-jet injection, and given his use of the FI main pump, I'm curious what other wrong-headed steps he took in doing the conversion. You might want to ensure there is no open return line somewhere, although this would not cause the problem you describe. Likewise, you should make sure the return line is not plumbed into your carb feed line. If there is, it might explain how your car ran with the wrong pressure, but installing the right fuel pump with low pressure with a return line will probably result in insufficient fuel pressure to the carbs.

Do you have a carburetor support rod? If not, you may be leaking at the carburetor flexible mounts resulting in a lean condition on one or more cylinders. You may have leaking flexible mounts even if you do have a rod, which might explain some of your cold idle issues.

Good luck.
 

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Discussion Starter #6
OK it gets even better! ALl the FI stuff is gone. hoses are all cut off at the fire wall and harnesses are laying zip tied on top of the subframe/fenderwell. The carbs are solid mount with o-rings. They are not soft mount! I have soft mounts on my 2002's webbers. He eliminated the VCT also when he emliminated the electronic ignition and FI. I have all the original componenets, but was told that none it was functioning and thats why he removed it all. I just want a reliable Alfa. hahahaha... It has a Bosch blue coil with some blue stock looking plug wires that I need to change. Plugs are new but when I inspected them I noticed the car was running evenly rich. The FI pump is an external pump that dosent seem to have any more pressure then the aftermarket pump I have on my 02'. I first thought a bad pump so I pulled the feed line off the back carb and turned the key on. It poured a nice stream out. Nothing at the rate of 45psi though. This is frustrating! Anyone want to take a vacation ito Fl and work on a spider? :) When I rebuilt these carbs I used my BMW service manual as they were a stock carb option on it. It seemed to run ok but kinda sluggish until the motor warmed. Then this whole ordeal happened.
 

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Discussion Starter #7
The PO told me the carbs and intake were off of a Berlina he parted out. He drove the car for 10 years like it is but running properly.
 

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alfa romeo 'L' jet is very reliable,, don't know why the p.o. took it off, you might want to think about going back to 'L' jet..you got a local pick and pull, out here on the west coast there is 1 or 2 'L' jet cars in there..
 

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Discussion Starter #9
The PO gave me all the Fi that came off of the car. So I have all of it as far as I know. Id like for it to be back to L-jet, but would really need someone who was more familiar than I am with it to get it all back together. I have had some BMWs and Porsches with jetronic, but never did a full tear down.
 

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'L' jet, is very esy to work with and understand.. i would re-instale it.. has the 'L' jet harness been cut up?
 

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Discussion Starter #11
The harness is neatly zip tied up in a bundle laying next to the carb on the inner fender. As far as I know its all there but ive never unwrapped it to see. I am trying to get in contact with the PO as the Fi system is sitting in his Alfa parts room along with my original 5 speed (bad bearing) and owners manual. He has multiple Alfas and knows the cars very well. All he said about the FI was "when I bought the car the FI was dead so I took the carbs off of the Berlina I was parting out and put them on it" Sounds like I need to have a "put Fi back on my spider party" Then I can invite all of you over!
 
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