3.0 CS: correct mounting of starter lid to carburetor Zenith Inat

Ulrich 3.0 CSA

Ulrich 3.0 CSA

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Hello all,
I may have a problem with the correct mounting of one of my starter lid of my 3.0 CS

problem was: one of the starter lid was loose (No 12 in drawing). So I removed it and checked it. The spring was Ok also it is electrical Ok.

I than mounted it again. BMW manual doesn´t say exactly how to mount it. You can put the driving dog arm (Pos17) in different positions while connecting it with the spring.

I tried it in different ways. If car is cold both starter flaps are mooving smooth from closed to maximum opened (if actuated by hand)
But after car was started and cooled down the starter flap of the one carburator doesn´t move to "fully closed " position- there is a resistance maybe 10 mm before "fully closed" position

Car will start and idle in automatic idle position. After I pushed the accelerator pedal it will idle at correct RPM.

Does someone know how to mount the starter lid 100% correct to the Zenith Inat carburetor?

Thanks Ulrich

17.png2.jpg3.jpg7.jpg
 
in the spring in the outer housing, there is a "square " end at the end of the spring, this fits over the pin on the auto choke housing. There are some small marks on both the housing and and the spring housing These can be used as a starting point. Once on, you can rotate the outer housing ( don't tighten up the 3 screws holding it on until you have done your adj ) to put either more or less tension on the spring, more tension will make the choke stay on longer You will have to play with this a little as every carb is a bit different

Thanks, Rick
 
Hello Rick,
thanks for your answer. Do you think it matters how Pos 17 (driving dog arm) of the auto choke housing is located when i put the "squre" on it? See my two fotos of the housing...there is more than one position possible, I think...will it affect the starting sequence?
And: Must I disconnect the two carburetors (the connecting rod) while putting on the starter lid?
Thanks Ulrich
 
no and yes It does not matter when you put the peg into the square of the spring but as you push the choke housing up against the carb side, you will see markings on the both sections that should line up, this is a starting point, put the 3 hold down screws and the plate in just tight enough to allow you to still rotate the outer housing. When rotating the housing, you can feel tension on the choke flap By rotating the outer housing will give you either a shorter or longer duration of how long the choke stays on and then as the coolant flows thru the top end of the engine warming the choke housing causing the bimetalic spring to slowly open the choke flap completely When first doing this, I would set the housing in the middle of the markings More tension on the spring with the eng cold will cause the choke to stay on longer. The fast idle speed is set by that little set screw at the bottom of the choke housing inside ( it is pointing downwards in your picture. Once the outer housing is on, you move the accelerator linkage slowly to open and just a weee bit of the head of that screw shows up in the open hole ( just off to the right side in your picture ) This part of adjusting that screw is a real PIA To get proper fast idle , disconnect the rod from the linkage to the back carb so they work independently . by pressing down on the as=cc linkage all the way to fully open, close the choke flap by hand, this sets the choke ( as if it was 20 below
 
then start the engine and see what the fast idle speed is, should be about 1400 rpm Then do the same for the back carb, same fast idle speed Then hook up your linkage again, all the way open for both carbs, while holding it open, again, closing both choke flaps with your hands holding them closed, release the linkage, don't touch anything, start the eng and you should have about 1600-1700 rpm as the fast idle The tension on the choke spring has no bearing on the fast idle/.idle speed other than controlling how quick the fast idle comes off and how it slowly comes down as the eng warms up more tension, slower it takes to come down in speed There are 2 more adjustments about the choke flap The diaphragm for initial choke "brake " or opening and the actual choke flap opening Let me know if you want to get into this

Thanks, Rick
 
I take an piece of welding rod and hammer down one end to a screwdriver thickness, grind the end to look like a screw driver and use that to set that PIA fast idle screw, easy to bend to fit thru, around. by the linkage to get to that screw PIA to get to I also jam the linkage open once I have opened it and can see the head of the fast idle screw, too hard to do trying to hold with one hand and adj with the other

Thanks, Rick
 
Thanks all,
drawing with correct numbers enclosed 11+12 is both lid. But 12 is the lid I am speaking of.
I will come back later
Ulrich
starter lid.png
 
Ulrich 3.0 CSA said:
Thanks all,
drawing with correct numbers enclosed 11+12 is both lid. But 12 is the lid I am speaking of.
I will come back later
Ulrich
View attachment 187508
Click to expand...

if so, then it was explained here:

stphers said:
in the spring in the outer housing, there is a "square " end at the end of the spring, this fits over the pin on the auto choke housing. There are some small marks on both the housing and and the spring housing These can be used as a starting point. Once on, you can rotate the outer housing ( don't tighten up the 3 screws holding it on until you have done your adj ) to put either more or less tension on the spring, more tension will make the choke stay on longer You will have to play with this a little as every carb is a bit different

Thanks, Rick
Click to expand...

And subsequent posts
 
The usual problem comes when you miss the spring square into the peg while mounting the two pieces together
my guess is that the 10mm resistance has something to do with this
 
Hello all,

thanks for all your info. The car was starting fine six month ago. There the "problem" with the "not stable idling" after starting ocured. I would say the starting mechanism is not misadjusted-as no one did so. So I think I don´t need to adjust any screws of the mechanism..
I recon that one starting lid was lose and was twisted to the right (awy from the RICH marking). I then mounted the lid three times and always the 2 starting flaps are equal (react in the same way when moved by hand) before starting the car ( I sure didn´t have missed the connecting rod with the square of the spring). But after heating up there is an "fixed point" at the carburetor I disconnected the lid (10 mm before closed)!?! Thats the problem.
Do I have to bring the starting mechanism in another/correct position while connecting with the square of the spring?
On my 2 fotos of the starting mechanism above you can see at least 2 different positions of the screw to the Stufenscheibe (stepped disk). I think there are 2-3 more (2-3 more steps of the disk)
Thats what I am right now thinking about. BMW manual says only "connect square of spring to lever"
Thanks for yout input and Regards Ulrich
 
Ulrich 3.0 CSA said:
Hello all,

thanks for all your info. The car was starting fine six month ago. There the "problem" with the "not stable idling" after starting ocured. I would say the starting mechanism is not misadjusted-as no one did so. So I think I don´t need to adjust any screws of the mechanism..
I recon that one starting lid was lose and was twisted to the right (awy from the RICH marking). I then mounted the lid three times and always the 2 starting flaps are equal (react in the same way when moved by hand) before starting the car ( I sure didn´t have missed the connecting rod with the square of the spring). But after heating up there is an "fixed point" at the carburetor I disconnected the lid (10 mm before closed)!?! Thats the problem.
Click to expand...
you must show pics of this

we are missing something
when warm, 10mm before closing ? That is not possible





Ulrich 3.0 CSA said:
Do I have to bring the starting mechanism in another/correct position while connecting with the square of the spring?
Click to expand...

no, not at all, those two mechanisms work independently



Ulrich 3.0 CSA said:
On my 2 fotos of the starting mechanism above you can see at least 2 different positions of the screw to the Stufenscheibe (stepped disk). I think there are 2-3 more (2-3 more steps of the disk)
Thats what I am right now thinking about. BMW manual says only "connect square of spring to lever"
Click to expand...

is correct they are independent

Ulrich 3.0 CSA said:
Thanks for yout input and Regards Ulrich
Click to expand...
 
Would be nice if the choke housing was off question why do all u tube people talk so much need more action, less talk maybe, I willl dig out the carbs that I have prepped for restoration and dig them out to show the bits inside and what they do

Thanks, Rick

Thanks, Rick
 
stphers said:
Would be nice if the choke housing was off question why do all u tube people talk so much need more action, less talk maybe, I willl dig out the carbs that I have prepped for restoration and dig them out to show the bits inside and what they do

Thanks, Rick

Thanks, Rick
Click to expand...

maybe, sure, you can do it better
enlighten us
apologies for my bad video
 
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