SPITTING CARB - 914-6 all stock, SEEMS LIKE I HAVE THIS FIGURED OUT! Options

[rgalla9146]

Don't trust the marking on jets.
Get a jet measurement tool to verify they have not been reamed.

[ctc911ctc]

*******UPDATE*********

I was getting pretty frustrated - ready to send the engine out to an expert and have it completely rebuilt.

AND HERE IS THE PART ABOUT 911WORLD's power

I received a message from a member stating he had a pair of original carbs and that he had them tuned and operating on an an engine stand with a 2.0 '70 914-6 engine running perfectly and that he would sell them to me. I bought them and put them on the car.

Double checked all of the connections, turn the key and.....battery dead??? Huh, must of left the interior light on.......got the charger and got some lunch.......looked for fertilizer for the lawn......must be around here somewhere....answered the phone, my son wanted to work on a project, bringing his car over......neighbor stopped by to ask me why his TOYO was doing something ridiculous..........and then I stepped on the gas 2 times and turned the key.

The car started on the first turn and purred........ (IMG:style_emoticons/default/beerchug.gif)

Did not even have the idle advance handle in postion....... (IMG:style_emoticons/default/cheer.gif)

One or two minor pops and then just silky idle.........

I could not run the car too much since it is Easter weekend - more to come!

[porschetub]

*******UPDATE*********

I was getting pretty frustrated - ready to send the engine out to an expert and have it completely rebuilt.

AND HERE IS THE PART ABOUT 911WORLD's power

I received a message from a member stating he had a pair of original carbs and that he had them tuned and operating on an an engine stand with a 2.0 '70 914-6 engine running perfectly and that he would sell them to me. I bought them and put them on the car.

Double checked all of the connections, turn the key and.....battery dead??? Huh, must of left the interior light on.......got the charger and got some lunch.......looked for fertilizer for the lawn......must be around here somewhere....answered the phone, my son wanted to work on a project, bringing his car over......neighbor stopped by to ask me why his TOYO was doing something ridiculous..........and then I stepped on the gas 2 times and turned the key.

The car started on the first turn and purred........ (IMG:style_emoticons/default/beerchug.gif)

Did not even have the idle advance handle in postion....... (IMG:style_emoticons/default/cheer.gif)

One or two minor pops and then just silky idle.........

I could not run the car too much since it is Easter weekend - more to come!

Wow great result ,well pleased you are sorted ,carbs you bought must be healthy ,yes if they are good just a few pumps on the loud peddle, I don't use my hand throttle much more than to warm the engine for a few minutes and it's also handy when I balance carbs.
I remember a while ago you were going to check vents, jets etc ,what did you find ? ,I suspect as others said your old carbs were setup wrong for a stock application 2.0 litre 914/6 motor.
All you need to finish up is to balance the airflow for YOUR engine , cheers.

[930cabman]

All is well that ends well. but what could have been the culprit? clogged passages/jets?

we may never know but at the least you can drive the car (IMG:style_emoticons/default/piratenanner.gif)

Happy Easter and happy motoring

[brant]

They need a full high end rebuild. Possibly butter flys.

Which cost thousands

[930cabman]

They need a full high end rebuild. Possibly butter flys.

Which cost thousands

Curious: I have heard/read of the throttle shaft air leakage, but if these IDA, IDT, 3V carbs can be dialed in at idle where air leakage should show up, how can this be an issue off idle?

small teflon pieces are the actual bushes?

[brant]

An air leak is unmetered air and effects mixture always

[Superhawk996]

They need a full high end rebuild. Possibly butter flys.

Which cost thousands

Or . . . More likely just the proper Venturi and jetting. 32mm Venturis on a 2L six cylinder is craziness unless racing and top end power is the goal.

Guess we’ll never know (IMG:style_emoticons/default/laugh.gif)

Regardless, glad the carb swap helped it and maybe now it can get driven. (IMG:style_emoticons/default/smilie_pokal.gif)

[ctc911ctc]

****UPDATE*****

I have another thread that talks about Bucking - MY guess is that my carbs are getting closer - most of the problem is my on the job learning curve. (IMG:style_emoticons/default/dry.gif)

The car was idling perfectly but on occasion would tap. Uh-oh - valves? (IMG:style_emoticons/default/sad.gif)

NO! turns out the carb throttle plate rod is oscillating laterally. Literately Laterally!
(IMG:style_emoticons/default/WTF.gif)

https://youtube.com/shorts/KFZnitg3QZU?is=92xMfJZFT57ZZkvQ

In this video, when i hear the tapping I PRESS against the throttle plate rod which I can feel oscillating laterally. When pressed the sound ceases.

My guess is that the throttle rod HEX collars need to be adjusted? Has anyone seen this before?

Thoughts (IMG:style_emoticons/default/confused24.gif)

[Superhawk996]

(IMG:style_emoticons/default/popcorn[1].gif)

Video looks like you might have gone back to stock Venturis but is there a reason Venturi size is being kept a secret?

Idle seems sort of rough and that may be causing the throttle shaft to oscillate? (IMG:style_emoticons/default/idea.gif)

And yes you need to make sure you linkage joints don’t have excess slop in them too.

There really shouldn’t be much lateral play in the actual throttle shafts but there are a few springs and washers along with a coupler between the two throttle shafts that could be loose. But having said all that, the thing that ultimately dictates lateral play is the slight but necessary clearance between the throttle plates and the throttle body.

Before I’d even think of tearing down carbs, I think you need to focus on tuning basics and see if you can smooth the idle shake.