Printable Version of Topic

Posted by: Spoke Oct 29 2004, 11:23 PM

I'm new to this board and looking for info on adjusting the choke on my progressive Weber carb (single 2 barrel, progressive Weber, don't know the model type). Just bought the car last year, 71 914 w/1.7L. When first started and the engine is choked and when fully heated, the car runs real good. But after the first couple of minutes (when the choke opens), pre-warm low RPM (below 2k) has almost no power and difficult to get off the clutch without revving the engine above 2-3K. The choke opens pretty fast and the engine thermostat is missing but on order. I have a couple of questions about the carb and choke setup:

1) Is there a setup or adjustment for the choke to change the speed at which it opens?

2) I've read about the stock FI intake where warm-air is circulated into the air cleaner. I can't find where the warm air comes from in the sheet metal and how would I (or do I need to) get warm air into the carb? The air cleaner is a simple snap on type. (See pic)

3) There's a hose from the crankcase to the carb from the oil filler that seems to be a breather. What is this for and how should it connect to the carb? Should there be a valve or something on this hose?

Thanks,
Spoke


Attached image(s)

Posted by: Series9 Oct 30 2004, 04:05 AM

Proper adjustment is achieved by removing that carb and throwing it as far as you can.

Posted by: Spoke Oct 30 2004, 06:10 AM

I don't want to spend much on the carb. What would you suggest for a replacement? Can I get it used?

Thanks,
Spoke

Posted by: tesserra Oct 30 2004, 06:56 AM

Those carbs are actually not that bad, on cars other than a 914.
The problem is that the intake runners are sooo long that the fuel mixture gets screwed up by the time it reaches the intake valve. The runners are cold and the fuel vapors condensate and kinda stick to the runners instead of staying aerosolised (sp).

The choke adjustment should be the standard, a little tension when bone cold then fully open in about 2 mins. Those chokes are usually electric heated, so they open to whatever you set them to, independent of the engine temp.

Having said all that I have no experience running a car in the winter temps of Pa. and you could have cold weather problems that I have never even heard of.

Good luck
George

Posted by: Spoke Oct 30 2004, 06:54 PM

Posted by: boxstr Oct 30 2004, 07:02 PM

www.redlineweber.com I believe they willhave the adjustment you need in teh table of contents. I have one on a ford motor, works great, electric choke, take s awhile to warm up.
Starting routine, turn on key, step on throttle, turn key, starting car, high cold idle, let run until motor tgemp increases then step on throttle to release choke, drive off.
CLINWEBERCARBS

Posted by: tesserra Oct 30 2004, 10:59 PM

If the choke is opening too soon you just adjust it so there is more spring tension on the choke plate by turning the cover of the choke heater. Usually 3 screws loosen the cover then you just rotate it the direction you want. There are usually detents marked on the adjustment, you should use those as a guide.

George

Posted by: Spoke Oct 31 2004, 06:55 AM

Posted by: Spoke Oct 31 2004, 07:51 PM