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Discussion Starter #1
I've got leaking throttle shafts on a 1973 Berlina with 40 DOCE Webers. From a diagram, it looks like the shafts are sealed with "O" rings on the venturi side of the shaft bearing.

1. Can the seals on #1 and #4 be replaced without removing the carbs? Will the bearings come off the shaft with the shaft in place?

2. I haven't got a rebuild kit, but a selection of metric "O" rings. Is there anything special about them? I have small sizes.

I'm running out of time to get this car operating well enough for the Berlinas to Bovine run. I need to leave Bellingham Sept 12 with only 2 weekends left. I'm getting worried I might not make it.
 

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40 DCOE butterfly air leaks.

Hi Richard,
If you are talking about the butterfly shafts, no o rings. You did not mention which series 40DCOE's these are, but the center of the shafts are supported with bronze bushings. On the older DCOE's, the shaft was brass, and the pump spring and lever had a tendency to bow the shaft, causing wear in the middle. The symptom was poor idle and slow drop to idle from air leakage past the bushings. The steel shafts eliminate this wear area. Years ago I carefully cut o ring groves in a new brass shaft in an attempt to solve this problem. I didn't work too well as the shaft still bowed and the butterflys ****ed in the bores making everything worse. I should have re bushed the bodies, but I was looking for a quick, easy fix. The steel shafts take care of that, now. I don't believe they were available in '65.
About anything you do with the butterflys or shafts will require carb removal, considerable Weber knowledge, and patience when resetting the butterflys on new steel shafts. The outer retainers, leather seal, spring and bearing are all a snug fits and again require Weber rebuilding knowledge to get the new steel shafts correctly centered. Finally, there is always the possibility that the throats are grooved by ill fitting butterflys. This can be a problem depending on the extent and area of the grooves. Could require new butterfly plates or ( :eek: ) new carb bodies.
Finally, are you sure that air leakage past the bushings IS the problem?
If you feel the leak IS on the OUTSIDE, pull off the washer, put a shot of oil through the retainer holes soaking the leather seal (if possible) then a blob of grease in the holes before replacing the washer. That will seal the outside enough to see if that is the problem. Unfortunately, DCOE's seldom leak enough air from the outside to be a problem. Most WEAR and leakage is in the center bushings. Does this help? :DGordon Raymond
 

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Discussion Starter #4
Gordon,
I'm not sure what's up, but I've double checked valve and ignition timing, points, plugs, wires, reblew out all the holes in the carbs.
I can't get it to run right. With the idle mixture screws on #2 and #3 out 1.25 and 1.5 turns, the #1 screw was out 3 turns still running lean and #4 out 2 turns still running lean.
I checked for vacuum leaks with a propane bottle and got increased rpm at the throttle shafts on #1 and #4.
I went through the method you gave me a while ago to adjust the carbs. I couldn't get the carb sync adjusted properly. My Unisyn won't seem to work at idle. I'm thinking I need to make a manometer, or buy a Synchrometer and Colortune.
 

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Discussion Starter #5
Alfar7,
Not really, have you looked at the pics on my other post? What do you think? Is it ok for the cams I've got? Would it cause a slow to return to idle?
 

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For some reason I never found leaks with propane, but as soon as I started spraying carb cleaner around I found leaky gaskets between the carb and the softmount. When I first started troubleshooting I retightened everything, but the gasket damage was already done so even though the nuts were tight, it still leaked.
 

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Refresh my memory, are the insulators (black rubber w/metal inserts) new? These are the softmounts GTV4EVER refers to. The rubber cracks & leaks with age, and as he mentions the gaskets are thin and easily damaged. I remember you have already replaced the manifold gasket, correct? What size idle jets does it have? If these were not correct to begin with, it could be the source of the problem. Let me know. Best, Gordon Raymond
 

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Refresh my memory, are the insulators (black rubber w/metal inserts) new? These are the softmounts GTV4EVER refers to. The rubber cracks & leaks with age, and as he mentions the gaskets are thin and easily damaged. I remember you have already replaced the manifold gasket, correct? What size idle jets does it have? If these were not correct to begin with, it could be the source of the problem. Let me know. Best, Gordon Raymond
They sure can :D
 

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The burned gasket I pictured had about 1 hour running time on it from new.
 

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Just talked with Alfar7, we agree it must be one of three things. Strange cam timing, too much back flow pressure. Too much static ign. advance, gummed up advance mechanism, broken spring, too heavy weights. Air leak, or plumbing plug up. Your main jets should be somewhere in the 130-140 range. air correction 200-210. Emulsion tube F-34 or(My favorite, F16) 50 or 55 F8 idle should be fine. So nothing wrong with jetting. I have had some non Pirelli softmounts where the steel face was not flat, and needed some "adjustment" to avoid gasket problems like those pictured above. If the problem IS carburation, it is either an air leak, or crud. You can rule out the dist problem by retarding the static about 4 degrees, and increasing the idle speed back up to 800-1000, blippping the throttle and see if the idle quickly comes down. If not, the problem is likely the mechanical advance mechanism. For the cams, you need to talk with Richard J, as I haven't a clue as to how they should be set in a 2L. We NEED some progress now! Best, Gordon Raymond
 

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Discussion Starter #12 (Edited)
Gordon, thanks for your help. I just now finished putting a clutch master cylinder and clutch pedal in my 164. I needed the break from the Berlina and am ready to go at it again.

1.Cam timing...I know the pics aren't great, but was hoping Alfar7 or someone else knowledgeable on cams would comment on my setting and the cam profile. I seem to remember a post of Alfar7 that hot cams need to be set a little off.
http://www.alfabb.com/bb/forums/showthread.php?t=47147

2.Distributor...At 7deg at 1000rpm I'm getting 35-40 deg at 4000 rpm. When I change to 3deg at 1000rpm and rev up to 3000, it's still slow dropping to idle. I had the distributor apart last week looking for gunk and didn't find any. There was a small amount of dirt that I washed out. Springs are intact and weights and center shaft move freely.

3. Air leak/plumbing plugged...I know I've got leaks around the throttle shaft at #1 and #4. The Idle increases with propane. I had the tops off the carbs again last week and blew out all the holes. They seem clear.

Maybe I'll take the carbs back off to look at gaskets, soft mounts throttle shaft seals and throttle plates and fit to the body. What do you think? This is my 1st 4 cyl Alfa and 1st shot with Webers. I may not be doing things quite right especially with Synchronizing the carbs. I may get a Colortune and either make a manometer, or buy a Syncrometer. If nothing else it will increase my confidence level.

Your right, I need some progress on this car!!
 

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Hi Richard, Ok dist is good. Of the choices you mention the Synchrometer is the easiest to use, just be sure you have a method of getting it stuck leaklessly in the carb opening.
Alfar7 will guide you through correct cam timing, possibly with photos (He IS GOOD!) Perhaps you can exchange photos.
Keep me informed. Best, Gordon Raymond
 

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Cams timing

Richard,
Is the head from a US engine or european engine. From the pics on the twin post I'm just wondering if your exhaust camshaft is pointing on the proper side of the caps' mark.
 

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Discussion Starter #15
I believe it's a US model. With the timing marks lined up, the cams point outwards like they are supposed to.
 

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Hi Richard,
I have no idea if it would have any impact on your described symptons but for what it's worth...I'm assuming you have 2l euro. camshafts with the lobe centers at 99.5 deg for both intake and exhaust. But your original SPICA cam bearing caps have marks at 114 (int) and 102 (exh). It's very difficult to tell but from the pic of the exhaust cam timing it seems to me that it's more retarded than the 99.5 deg called for. I read somewhere on the bb that the thickness (width) of the cam bearing cap mark is about 3 deg. so the camshaft mark shouldn't be very far from the right edge of the exh. cap mark.

my general cluelessness disclaimer applies here...
 

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Discussion Starter #17
OK, this is something else I need to check. Is there a template or something to set Euro cams, ignoring the timing marks on the cam bearing caps? How do you do it?
 

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Discussion Starter #19
Interesting! I don't know if I can use this information unless I know what cams I have, which I don't
 

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Discussion Starter #20
Lobe centers

After spending the evening looking at Jim K's book, page 54, I think performance may increase if the lobe centers are adjusted, but being off slightly will not cause the problems I'm seeing.

Tomorrow I'm taking the carbs off again to look for a bent throttle shaft, leaks around #1 and #4 on the throttle shaft and the fit of the throttle plates in the carb bore. Wish me luck.
 
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