Carburettors, Balls, and the Road to Eldorado

[mummyjohn]

On the final steps of my 1971 Eldo resurrection here, and I've encountered two separate mysteries.


1.
See the first picture - back side of the carburettor.  I know for sure that the blue hexagonal "T" fitting (cyan arrow) has been reconnected exactly as it was originally.  The hose going out the side of the T was labeled and photographed when removed, and then the T was unscrewed from the intake and was never disconnected from the hose that comes up out the top.  That top hose connects to a metal tube that goes down to the transmission - the vacuum modulator, yes?

Now according to literature, the nipple on the carb with the ORANGE hose on it is supposed to be for the trans vacuum modulator.  As for the short hose sealed with a screw (yellow arrow), I cannot determine what this port does.  The car was set up like this when I got it.  If you know, share.

But my real question is what should that orange hose be connected to?  I'm awfully sure it was connected SOMEWHERE, since it was on the car originally and it ran fine then, but I can't for the life of me determine what.  All I know is it definitely wasn't the vacuum modulator, since that's serviced by the tee and the tee definitely is connected as it was originally.  The orange is about 1.5 feet long and I'm not spotting anything obvious.

Add'l info: in the manual, instructions to remove the intake manifold say "disconnect air con system vacuum hose from rear of manifold," which I assume is talking about the T fitting since nothing else in the instructions could reasonably be referencing that T.  Yet in the engine removal instructions, it says "Remove vacuum hoses from rear of carburetor and hose from tee at rear of intake manifold."  Anyone with a clue about this stuff, spread your wisdom.


2.
Underneath the car I have found these two little metal balls.  They're about .375", or 3/8, diameter.  While it is technically possible they could have rolled over from the numerous contraptions I have in the vicinity, I am keen to assume they are from the car.  Do you have ANY idea what these are?


With solutions to these mysteries, I can be back on the road tomorrow!!!

[TJ Hopland]

I don't have a 71 manual so just guessing.   

That high capped hose would not usually be vacuum, it would be a filtered air source for something.  The level ride compressor would be on possibility but I think that would have been a larger hose.    Usually what was connected to those was one end of a choke stove but I don't ever recall Cadillac using that type of choke.   Maybe you don't have a Cad carb?  Or the top isn't part of a cad?

Transmission is typically a hard line with very short sections to make the connections at each end.

One vacuum connection would be for the climate control and would be a line through the firewall.   I'm not sure on a 71 if that is were the parking brake release gets its vacuum or if there is another line for that.

Do you have cruise control?   That would have a vacuum connection. 

EFE?  Heat riser in the right exhaust manifold?

Where is your distributor connected?    I think a 71 still had that solenoid connected to a speed sensor on the trans so that would be extra plumbing that often gets disconnected.

[fishnjim]

No way to visually ID, but the "balls" look like to me the ones in a steering gear but not possible to come out, unless was repaired on the car.   Could also be from a wheel or other ball bearing, but think wheels were roller by '71(?).  Drawer slides, etc. use them, so maybe not even from this car.   Spherical things roll a long way.

["Cadillac Kid" Greg Surfas 15364]

First of all, IF the two balls are from your car they would be for the front ash tray slide.
The tee fitting is where the vacuum source for 1. Air conditioning/brake release, 2. vacuum source for cruise control 3. Thermac Air cleaner damper
The fitting you have the orange line connected to is for the transmission modulator.
Greg Surfas

[klinebau]

That high capped hose would not usually be vacuum, it would be a filtered air source for something.  The level ride compressor would be on possibility but I think that would have been a larger hose.    Usually what was connected to those was one end of a choke stove but I don't ever recall Cadillac using that type of choke.   Maybe you don't have a Cad carb?  Or the top isn't part of a cad?

On the '70, the fresh air port on the carburetor connected to the TCS solenoid (transmission controlled spark).  The idea was disable vacuum spark advance when the transmission was in first gear.  This was intended to reduce NOx emissions.  I do not know if that was used in '71.

[mummyjohn]

There was a TCS that disabled spark advance in first and second in '71, if you can believe that.  It appears to have been bypassed on this car.

I do believe the tip about the air cleaner damper is the golden answer, Greg!  I had identified more vacuum sources than things which demanded it, for I'd not thought of this.  The hose going out the side of the T goes immediately through the firewall, so pretty sure that's the air con.

Level ride control would usually draw vacuum from a T in the line from the carb to the PCV valve, which indeed is much larger than this.  On this Eldo however the pump has been disconnected and the tank routed to a tyre-valve style fitting in the trunk; I understand that was common practice on these cars by "local"/non-Cadillac mechanics since the system was novel and they weren't familiar.  There's simply a note on it that says "maintain at least 20psi"

The carb's numbers are sort of odd (don't follow the common QJ numbering scheme); it is a "service replacement" carb that was put on at a later date.  IE it is for a Cadillac, it's just not original.

Distributor is connected on the front of the carb, hose goes directly from carb to distro.  Still think that means it's ported vac though, yeah?  What's y'all's opinion on switching over to straight manifold vac.....recommended here?  I figure I can experiment with both and see how temperature/mileage/performance gets affected, but if you have experience tell me whatcha know.