Cleaning 40 DCOE's

[Richard2]

I'm cleaning the Webers in place to try and improve the 20 minute and 2 batteries it takes to start this 1973 2L Berlina. Some stats first:

Main Jets F9 130
Idle Jets F8 50
Pump Jets 35
pump exhaust valve 60
Starter air jet F5 65

It's got stock pistons and with 252 deg cams.

I'm using Gum Out as suggested in other posts, soaking the jets in acetone and the carb body in Gum Out. I blew every hole I could find with Gum Out. I cleaned the carb strainer and blew out the float valve. Some holes had lots of dirt. Particularly the holes in the bottom of the bowel. The ones in either corner on the bottom.

Also, I noticed there is only a Throttle Adjustment Screw on the rear carb, not one on the front. Is this normal? Do you adjust the rear one with this screw and the linkage adjustment for the front one, or should both have adjustment screws?

I'm on a steep learning curve!

[Richard2]

I just checked a pic in Jim K's book. Looks like there is only one Throttle Adjustment Screw, so I guess the throtte adjustment on the front carb is done with the linkage connection screws.

[Gordon Raymond]

Pull the pump while you are at it. It often gums, and could be the reason for the...um ... difficult starting. It will come right out with a small pry of the brass hold down. Use a syringe to de-goop the smaller passages. Good luck. Keep us informed. When you get it all back together, ASK for additional instructions on air correction adjustments and balance with the linkage you mentioned. (It looks totally correct & un-messed with. Don't adjust it without asking for information.) There are LOTS of us out here that know Webers. If you have a question we will help! Gordon Raymond

[Richard2]

Ok, I didn't know how it came apart and read somewhere that it gets stuck. I didn't want to break anything. Will the accelerator pump piston come out without turning the carb upside down? It's still attached to the car and I don't want to dent the roof

As far as being "unmessed" with, incorrect. I messed with it when I took the carbs off to replace the head gasket, so the Idle Adjustment screw and the screws that adjust the linkage on the front carb have been severely "messed" with. On the positive side I haven't adjusted the idle mixture screw

The liquid you see in the chambers is Gum Out. I used a syringe to evacuate the remaining gas. When I pull the pump up and down, it seems to move Gum Out all over the place.

The pump jet has a flat on one side. Does it have to go back in a certain way? Also, several of the jets have small single holes drilled on the side. Do these have a special orientation?

[Gordon Raymond]

Quote:

Originally Posted by Richard2 Ok, I didn't know how it came apart and read somewhere that it gets stuck. I didn't want to break anything. Will the accelerator pump piston come out without turning the carb upside down? It's still attached to the car and I don't want to dent the roof #1)As far as being "unmessed" with, incorrect. I messed with it when I took the carbs off to replace the head gasket, so the Idle Adjustment screw and the screws that adjust the linkage on the front carb have been severely "messed" with. On the positive side I haven't adjusted the idle mixture screw #2)The liquid you see in the chambers is Gum Out. I used a syringe to evacuate the remaining gas. When I pull the pump up and down, it seems to move Gum Out all over the place. #3)The pump jet has a flat on one side. Does it have to go back in a certain way? Also, several of the jets have small single holes drilled on the side. Do these have a special orientation?

[Richard2]

I read about the Al washer on the pump jets, so looked for them when the jets came out. I have them. Oner major success story

I'm headed out to the greenhouse now to finish cleaning and reassemble.

Once it's running and warmed up, I'd like to run through the procedure for balancing the air flow and idle adjustment, if you'd care to elaborate?

[Gordon Raymond]

After reassembly, back out the idle adj screw on rear carb with the throttle linkage (from gas pedal) disconnected. The plan here is to COMPLETELY close all four butterflies. Lift up on the little ball of the linkage, and turn idle adj screw in & out to be sure butterflies of #2 (rear carb) are closed. Holding the little ball up, now act on the hex screw that links the two carbs together. You want the slack in the spring removed (spring toward manifold) and the hex adj screw out j u s t far enough to insure that the butterflies of #1 carb are also closed. You can push the "u" shaped link toward the manifold, (with your third hand) to insure #1 is also closed. WHEW! (have a beer{see "what beer do you drink" thread in this BB for advice}) Now, turn in the idle adj screw on carb #2 until the butterflies begin to open. (linkage will begin to move).
From this point, turn in an additional one revolution. this will give you a very fast idle.
Next, air correction screws (4). Turn in all 4 until they g e n t l y seat. Force here can push them through and inlarge the correction hole (BAD). Once seated, back off each 3/4 turn.
Re attach disconnected gas pedal linkage. Now you can try to start the car. Once running, back off or turn in idle adj screw until idle is 800-1000 rpm. Engine may not be running very well.
starting at the front, act on each air correction screw in what ever direction it takes to increase idle speed. This should not be more than 1/2 turn in either direction. If idle gets above 1000 rpm while doing this, back off idle adj screw to get it back to 800-1000. After all 4 are adjusted, do it again, starting from the front. Once you are satisfied that you have this about right, ONLY THEN try a slight adjustment of the hex screw on the connecting linkage. You are now balancing the butterflies by "ear and feel".
Turn this screw in and out about 1/2 to 1 turn listening and feeling for the engine to run smoothly, noticed by lessening vibration. Check idle, still should be 800-1000. Adj as req. Engine should be HOT by now. Lower idle to about 800 and again try adj. all 4 air correction screws for max engine speed. Again, a slight check of balance adj screw for s m o o t h n e s s.
Finally, set idle where you like it 800-1000 or a little higher if you prefer.
Do NOT mess with balance hex screw again unless engine is not smooth. (You replaced the plugs and checked the ignition, didn't you?) Ignition timing and ignition condition are the # 1 reason for hard starting, bad running Alfas. (remember rule 1: "don't mess with the Webers")
Now, shut it off and have another beer. Best, Gordon Raymond

[101/105guy]

Excellent tech advice and very timely as I too am cleaning out the Webers on the project Duetto.
Something I am wondering.....how to renew the 'gold cad' finish on the hardware and jet cover?

[Richard2]

101/105...good question. I'd like to know that myself. I think I read a post in the Detailing section that it is plated, or was it in the 164 section. I loose track.

[101/105guy]

Yea, originally they were done in 'gold' cadmium finish, but doe to the hazardous nature of cadmium in the environment, it's not available any more.

[Richard2]

Gordon...Thanks for all your help and good advice. The pump came out without any problem. I cleaned them up and reinstalled. I finished the rear carb. Blew out all the holes and passages. I was surprised at the debris that came out when I blew the holes. I expected the Gum Out to dissolve it. Not so.

On front carb I was not so lucky. The starter jet passage (1. in the pic) won't clear to the bottom of the bowel (2. in pic). All of the other 3 barrels blew air from the starter jet passage to the hole in the bottom of the bowel. I had the starter jet passage full of Gum Out and the bowel 3/4 full of Gum Out over night. I tried blowing air both ways without any success. Any suggestions?

[Gordon Raymond]

That does happen. Gron Perry (no longer @ Pierce Manifolds) calls that bottom jet a "bleed back jet". An excellent name. Time for the copper wire.
Take a stranded hunk of lamp cord, or larger, depending on how stiff or long it needs to be, peel the insulation and use a single strand to fish around down the hole from the starter jet side. The copper is soft and will not harm the passage (much) and may dislodge or expose the goop to the gumout. Unfortunately, the plug is often at one of the corners of the passage. Keep at it with the gumout. You are a plumber now, using draino and a fishtape!
Both passages are interconnected on the carb body bottom. When you dislodge the plug, it MAY pass to the other side.(Darn!) With compressed air and gumout, spray carb cleaner, laquer thinner and anything else you can think of, the idea is to get it loose and blow it out. Do not give up until both sides are clear. Second worse case, you may have to remove that carb and put it in an ultrasonic cleaning tank. Worst case (UGH) is to remove the carb, drill out the lead plugs on the bottom passages, clean them mechanically (thicker copper rod) and replace the lead plugs. (#4 lead shot and a punch {sometimes a wee bit of locktite blue as well} works well.) This is the LAST resort, and NOT fun. (No beer). Let me know what happens. Overall it sounds like you had SERIOUS crud issues! Best, Gordon Raymond

[Richard2]

Ahhh, so the 2 bottom holes are connected? So if I plug the starter jet holes on #2 cyl, I can try blowing from the bottom hole by #2 over to the bottom hole by #1? I think the pluggage is not straight down the holes, but around the bend. I already very carefully had a wire down the hole.
If I take it off for ultrasonic cleaning, I might as well do both of them. Do engine builder have Ultrasonic cleaners?

I started the linkage adjustment per your instructions. Unfortunately, I won't be able to complete it. I hate beer! With you permission, can I substitute whiskey and diet coke if I promise to upgrade to Crown Royal?

I'm about out of time this weekend. My work week starts on Sunday and I have to go hear Chuck Israels' jazz concert tonight.

[Gordon Raymond]

Any beverage is totally acceptable. The hole in the bottom of the pump, the bleed back jet hole, the starter jet holes and the pump jet holes, are all interconnected underneath the carb body. By applying air pressure to the hole in the pump bottom, it should come out of the bleed back jet hole. If you plug the bleed back jet hole, the air "SHOULD" come out of the two starter jet holes. A plumbers dream!
If all else fails, be sure the ultrasonic machine uses a petro. based solvent.
Water based solvents, will over time, rust up the ball bearings the butterfly shafts run in. not good.
The plug is ALWAYS around the bend. Thats the lowest point, and the hardest to reach. Most Weber cleaning work is really plumbing blockages.
Keep me informed! Best, Gordon Raymond

[Richard2]

I had a few minutes this afternoon to look at the carb again after I soaked it for 30 hours in laquer thinner. The bottom hole still won't clear, so tomorrow morning I'll call around to find someone with an ultra sonic cleaner.