weber electric choke tuning

[dlb]

do any of you fellow weber users have any tips on setting the electric choke the 32/36 DGEV? on my 3A, i had problems with the car bucking when it was warm and had the exact same thing when i first put the 4A in. loosened off the plastic choke dial and turned it clockwise: the electrical contact tongue originally pointed to approx. 2 o'clock and i set it to about 5 o'clock. bucking gone. now that the weather is colder though i need to actually set it properly but i'm finding that even when the car is running, i can rotate the dial as much as i want and nothing happens. is this as simple as just rotating the dial, setting it, and giving it some throttle to engage the new setting or something? that's easy enough to try but the contact on the end of the wire broke off while i was messing around so i thought i'd ask while i wait to pick up some crap tomorrow. i know i have a current coming through the wire because i get a tiny spark when i touch the wire to the tongue.

sorry for my lame terminology- tongues? come ooonnnnnn. but i don't know what else to call it.

[Petros]

I do not have experience with a weber on a Tercel, but I grew up with carbs on all car engines, and my first 4 cars had manual chokes (you open and close it from a knob on the dash, adjusting it to the engine temp "by feel"). All of the early "high tech" automatic chokes were adjustable (that was on BS cars-"before smog").

The best way to set it is by trail and error, you keep adjusting it until it starts good in all conditions and temps. And there are almost always some conditions where it will not be "just right". that is the nature of carbs with chokes, and one reason they when to EFI to reduce emissions and improve drivablity and economy.

[SynthDesign]

Your doing it right. Turn the car off, let it cool for a bit and re-test the electric choke setting. It took me a few times of trial and error before I was happy, and it must be re-tuned every time there is a major barometric change. I found a happy medium setting and turn it a few degrees when it gets below freezing and back in the spring.
Also too much fuel will cause the choke to be ineffective. Also make sure the choke is not operating while the engine is warm by looking down into carb. if you can't tell from idle alone.

[dlb]

perfect, thanks!

[dlb]

i've messed around with the choke a bit and still no action yet. i've tested the lead going to the choke and it has current so i don't think the problem is there. today i loosened off and rotated the choke adjustment wheel, opened the throttle for a second, and then checked the idle speed, but the engine idled quite low (around 500 rpm) regardless of where the choke wheel was set, and regardless of whether the lead was connected to it. so i guess there's something mechanically wrong with the choke, and that's making me panic because i don't know sh*t about carbs. i've googled this and all i can find is the redline troubleshooting guide that says how to set the choke properly and that the choke should have a 12 V lead connected to it. any further help on the topic would be massively appreciated. oh yeah, both the fast and regular idles are good and work correctly.

thanks!

[SynthDesign]

So what your hinting at is that maybe the electric choke solenoid took a poop?

I'll ask my weber friends on how to check this. If I remember correctly, replacement isn't very hard at all.

[dlb]

syyyyyynth, you're making yourself very popular in my books with this thread. thank you in advance.

[SynthDesign]

Just happy to help.

The Weber carb thing has been a learning lesson for myself as well. The best part is these carbs have changed very little in the last 5 decades so there's lots of knowledge out there to be had.

Either way, I'll be seeing my friend this weekend and will ask him. Between him and his friends, I bet there's 40 years of experience.

[SynthDesign]

Also, if it took a poop, I may have a few to pick from in my pile of used webers.

[Petros]

if I recall correctly, they do not have a solenoid on the choke, but a bi-metal coil that opens the choke as the electric element heats it up. They do fail, they delaminate, or the heater element burns out. easy fix with new parts.

[SynthDesign]

@Petros,
You're correct, it's just a coil thingie with a lead hooked to it. Not a solenoid. I used the wrong terminology.

[dlb]

hmmm. i don't know then because i manually held the choke open and opened the throttle for a second to see where the idle would settle at afterwards, but the revs never changed. even if the coil is delaminated, as long as the choke is open the revs should pick up a bit, right?

[Petros]

not sure of your question, but the idle would not speed up when the choke is all the way open. It should slow down from when the choke is fully closed (or fully activated), than as it opens the fast idle speed drops down. from about half open to fully open there should be no change in idle speed.

The throttle controls engine speed, including at idle. The choke only makes the mixture more rich when the engine is cold. There is a fast idle cam connected to the throttle that is also linked to the choke to speed idle up when cold so it does not stall out the first time you try to drive off. But that releases the throttle when as soon as the choke starts to open.

[dlb]

sorry, i had it backward. so what i mean is when i manually close the choke it should make the mixture richer and thus keep the idle up so the engine doesn't stall. but no matter where i set the choke, after the fast idle disengages the engine idles low (400-500 rpm) until it warms up and idles normally (800-900 rpm). i've taken the adjusting wheel off and can see the little door that opens and closes to make the mixture rich or lean but regardless of whether it is open or closed, the engine still idles low. maybe it's plugged with some crud in there. i don't know, i'll mess around some more tomorrow. i understand it better now so that might help me solve it.

[Petros]

There should be a separate fast idle adjustment for cold start. That is always true with carbs, it just sounds like that needs to be adjusted up a bit. I do not recall the details of the Weber that well it has been years since I messed with one (I have rebuilt them before, some 30+ years ago), but all carbs have pretty similar adjustments.

If you do a web search you might find a website with info on tuning the weber. they are still popular and likely there is a lot of information out there on them. Several production cars even used them back in the day.