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Discussion Starter #1
Hi All,

I am determined to get the throttle adjust cable corrected in my 750.

I measured the diameter of the cable in my car and came up with 0.048". Then I ordered 3 different types of wire from McMaster-Carr to be sure that I got one that would work. I ordered .049" stainless in hard temper, and then .049 in carbon steel in both hard and soft temper. I am hoping to use the stainless, but the cost wasn't high so I figured it was cheap insurance to buy the other two at the same time.

I was able to get the mechanism out of the car last night without much trouble.

I have seen a disasembled mechanism (at least the end away from the knob), and the cable is simply crimped into the end of a rod. I am pretty confident that I can replace the cable.

But I couldn't take the mechanism apart...struggled with it for quite a while. I didn't want to put too much force on it before I went out for some tribal knowledge on the subject.

As I said, I have seen one of these apart, so it must be possible. I can also see on my part that someone in the past has put some pliers on this thing, so I am not the first person to think of it.

Alright, how is done? As always, I will include some picture. If we can figure this out, I will also post details on replacing the cable, etc.

The first picture shows an overall view of the part. The second is intended to show a hole in the side. There is a rotating bit with threads inside that has a slot in it. As the knob is turned the slot and the hole will line-up once per rotation. I suspect that this hole is used to freeze the mechanism for disassembly. I tried it a bit with a paper clip, but the clip bent to heck before anything broke free and I got nervous about putting more force on it after that.

Cheers!

Jon
 

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Discussion Starter #2
Got it done, some picts.

So, I was finally able to work this out. After reading a couple of accounts on the Yahoo 750/101 group, I took another stab at it. The descriptions there didn't make a ton of sense to me since they lacked pictures, so I will post a few here in hopes that this saves some people some frustration in the future.

The trick is to move the brass sleeve down the shaft, away from the knob. The descriptions on the Yahoo Group say to slide it back, but this little bugger is on pretty tight. So, sliding is not the right word, IMHO. I had to take a vice-grip and another pliers to get enough torque on it to make it budge. But, I got it down eventually.

It appears that the two holes that I showed in the initial post are not directly involved in the disassembly. There should be a brass pin or rivet that goes through there, but it is missing on my mechanism. The purpose of the pin is to keep the inner workings from rotating when the knob is turned, and that would explain some of the sloppiness of the workings that I had previously noticed. If this pin is in place on your mechanisms, it would have to be removed (and replaced afterwards) before you could disassemble. That is because the pin would also prevent the sleeve from sliding down enough.

Anyway, when the sleeve is moved down, it reveals two semi-circular keys. The key ride in a groove in the center shaft and keep the knob itself from being pulled out. Remove and save the keys. They just fall right out.

Take a look.
 

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Discussion Starter #3
moving on...

The guts of the mechanism pull right out with the semi-circular keys removed.

The key to replacing the cable at this point is to un-solder the cap on the slotted, threaded brass fitting that holds the end of the cable. There is a 90-degree bend at the end of the cable with just enough wire beyond it that you cannot remove the cable. With the cap removed, the slot easily flexes enough to remove the cable.

I used a plumbers propane torch to un-solder the cap, but that is overkill. A soldering iron would be plenty--it's just that I don't have one, and I was getting impatient. ;)

Take a look!
 

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Discussion Starter #4
re-assembly.

Putting the thing back together is easy.

My biggest trouble was dealing with the spool of wire that I bought. I discovered why it came packed with tie-wraps firmly secured to it. That was because the wire naturally wanted to be in a 10" diameter, and they had wound it down to a 4" diameter. I hadn't had so much fun since I had detangled a Slinky when I was a kid.

Anyway, the stainless wire works great. Just bend a 90-degree bit on the end that looks like the old one and put it in. Re-solder the cap.

I used a small file and some 1000 grit sandpaper to smooth the solder down. I have also read the the mechanism should not be re-assembled with grease. However, mine had grease in it when I took it apart, and the way things look, I think that it should have some. So, I lightly greases things as I put them back together.

Put the keys back in place, and use the pliers to reposition the brass sleve over the keys.

Since I did not have the brass pin on mine, I used a cotter pin to put through the two holes. The mechanism definitely felt more precise with the cotter pin.

The first picture is of the threaded, brass bit with the new length of wire attached right before I re-assemble. The other two are of the assembled mechanism.

One note is that I used emory cloth and the fine sandpaper to polish the brass sleeve since it took a couple of marks from the pliers. If I were to do this again, I think that I would cut a couple of strips from an aluminum can to protect the brass.
 

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Discussion Starter #5
installation

Then I just put it back in the car.

I had left a pretty long length of wire sticking out past the cable housing to be sure that I had enough. I didn't want to do this again! :D

There is a picture from PapaJam in another of my posts of how the end of the cable should be configured. But, I have a couple of dissenting opinions on that, too. So, I am still trying to figure out how that part should go.

Help with this would be very appreciated!

I hope that this makes things easier for someone out there...

Jon
 

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Thanks for posting all this, Jon. I need to go through exactly the same exercise with mine and I've been putting it off not knowing what I would be tearing into. It looks pretty straightforward as do most jobs on these old birds. And to think all these years I've been wedging my steering wheel Club behind the brake and in front of the throttle to get the same effect!

Mike Hollinger
Atlanta
 

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Discussion Starter #7 (Edited)
no prob!

Thanks for posting all this, Jon. I need to go through exactly the same exercise with mine and I've been putting it off not knowing what I would be tearing into. It looks pretty straightforward as do most jobs on these old birds. And to think all these years I've been wedging my steering wheel Club behind the brake and in front of the throttle to get the same effect!

Mike Hollinger
Atlanta
No problem, Mike. PM me with your address, and I will mail you a length of the stainless wire on the condition that you post a blurb on how it went and any improvements that you thought of. Spreading Alfa knowledge is what it's all about...

Jon
 

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Jon
Nice write up!
Note: Please steady your camera when taking a close up pic - it keeps the details from blurring.

Not to put too fine a point to this but if you really want to duplicate the factory original terminating end of the inner cable, it should extend an inch or so beyond the brass locking barrel (with a hex-head screw) and end with the wire bent into a square (approx. 1/2 inch).

Picture of same on a 105 chassis:
 

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OK, it didn't take long to get stymied. Some of the pictures show the black plastic knob on the assembly and some off. I've taken out the set screw and regardless of how I twist or pull it won't come off. Does it need to? If so, how? Can/should the knob removal wait 'til later?

Mike
 

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Discussion Starter #10
doesn't matter

OK, it didn't take long to get stymied. Some of the pictures show the black plastic knob on the assembly and some off. I've taken out the set screw and regardless of how I twist or pull it won't come off. Does it need to? If so, how? Can/should the knob removal wait 'til later?

Mike
Hi Mike,

I toyed with the knob for a long time before I realized that it wasn't involved with replacing the cable.

To get the knob off, I removed the set screw on the side. I then unscrewed the knob until the mechanism bottomed-out. (counter-clockwise, I believe) Then, I increasing torque in the counter-clockwise (normal loosen) direction until the threads on the knob broke free. The knob is just untreaded normally and it will come right off.

Perhaps there has been some corrosion onset in the threads making it a little tougher for you.

But the knob can stay on for the process of replacing the cable. The important thing is to move that brass sleve down to expose the keys. Then the mechanism will slide out whether you have the knob on or not.

I hope that helps.

Jon
 

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Discussion Starter #11
not so!

Jon
Nice write up!
Note: Please steady your camera when taking a close up pic - it keeps the details from blurring.

Not to put too fine a point to this but if you really want to duplicate the factory original terminating end of the inner cable, it should extend an inch or so beyond the brass locking barrel (with a hex-head screw) and end with the wire bent into a square (approx. 1/2 inch).

Picture of same on a 105 chassis:
Hi all,

I have just been able to get a picture of an original, untouched throttle cable. It looks nothing like what GTD posted.

BTW, GTD, it isn't that I am shaking the camera. It's that stupid autofocus thing. Sometimes, lately, the camera I have just refuses to focus on the obvious. Other times it works perfectly. Maybe I should read the manual. :rolleyes: Anyway, I had similar difficulties this time despite taking three pictures.

Here is the best of the three. I finally put the $1 bill in there in an attempt to get the autofocus to do its thing. Yeah, right. Well, at least it might also serve to help people judge how big the loop is...

Cheers,

Jon
 

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To get the knob off, I removed the set screw on the side. I then unscrewed the knob until the mechanism bottomed-out. (counter-clockwise, I believe) Then, I increasing torque in the counter-clockwise (normal loosen) direction until the threads on the knob broke free. The knob is just untreaded normally and it will come right off.

Perhaps there has been some corrosion onset in the threads making it a little tougher for you.
Yeah, 47 years of sumthin' clogging the works. A shot or two of PB'laster and the knob is off. I'll be back on it tomorrow.

Mike
 

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Jon,

Sorry to disappear on this topic. I ran into some health issues in mid September and I really haven't been able to get back to this project 'til now.

I recieved the length of wire you generously sent but ... I don't think I need it! After extracting the cable from the dash (a chore in itself without a very short 19mm wrench) I found my 101 assembly is sealed and undisassembleable. No pins, no sliding sleeves, no way to get into it. Out of curiosity, assuming the assembly was junk, I chucked the free end into a vise to see if the wire was broken by pulling on it. Turning the knob caused the wire to extend and retract exactly as it is supposed to! I have no idea why a little tension on the wire restored it's function but I'll take little victories where I find them.

Here's a picture of the business end. Looks monolithic to me.

Mike Hollinger
Atlanta
 

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This is a great thread. A question is addressed here that many Giulietta / Giulia owners just give up on. Your photo essay is great. I had to ruin the first one I attacked 40 years ago, when they were common used. This will save many of the remaining original units that just need the wire! THANKS JON!!
Gordon Raymond
 

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No Prob!

This is a great thread. A question is addressed here that many Giulietta / Giulia owners just give up on. Your photo essay is great. I had to ruin the first one I attacked 40 years ago, when they were common used. This will save many of the remaining original units that just need the wire! THANKS JON!!
Gordon Raymond
Sure, not a problem.

I have taken a lot from this board, and I am more than happy to give back. If everyone made a little instruction manual for all the tricks that they know, the whole alfa community would be a ton better off. I know that it is alway hard to find the time, but a little of this can go a long way towards saving an old part or an old car. And old Alfas deserve to live.

Anyway, I have a few more of these things in mind as I sort out the remaining kinks in my 750. Maybe it will help somebody out.

Now if I can only find a complete 750 normale fuel pump...:)

Jon
 
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