Dying at idle without choke - 1976 Solex w/ water choke

[cw549]

Had the car running beautifully for a few months, went for a drive and she won't idle after warming up any more. I plugged the vacuum lines off the carb to check for a vacuum leak and this didn't solve it, so i sprayed some starter fluid around the base of the carb and various other areas while running and so far only a minor difference in revs when i spray at the intersection of the throttle shaft and the carb (minor as in 100-200 increase in revs at the most).

I am going to reseat the carb and check the seal/gasket but i feel like the starter fluid would have identified a leak here... any other tips?

[c.d.iesel]

spraying soo much 'stuff' may be just sucking up into the air cleaner

giving you that slight raise in rpm

i would guess the idle jets being dirty

you say you have an Original SOLEX on the car?

do you know which SOLEX? single or dual throat ?

is it just a rough idle or is it stalling?

does the motor react to slight Idle Mixture Screw adjustments?

[Timmer]

I'm guessing being a '76 2002, it's the 2 barrel Solex, I think the single barrel to 2 barrel change was late '72 or "73(?), that is, if you're '76 2002 has the stock Solex; every carburetted '74-'76 2002 I've owned had a Weber 32/36 conversion done prior to me buying the car so the only bimmers I've had with Solexes were '71 and prior; I'd agree with CD, clean the idle jets; cleaning the idle jet of the single barrel Solex was common for myself and many others here. Use compressed air or let the jets sit in carburettor cleaner for a bit, don't stick anything in the jet orifaces.

Tim

[cw549]

Yes it is the original solex, a dual barrel. (i think technically its a progressive carb? could be wrong tho)

It runs rough at idle and then dies if left to its own devices, ( as in if i use the throttle to keep it at around 1000 rpm it runs poorly) i had the mixture screw adjusted perfectly before, but i will go in and attempt to clean the idle jet now.

[cw549]

awesome thanks for the help, ill update in bit!

[c.d.iesel]

..............

[Conserv]

If you don't know when that Solex was last removed, stripped down, and cleaned, and the idle jet cleaning doesn't do the trick, consider stripping it down, cleaning it, and re-assembling it (or having someone do it). I still run the original Solex on my '76 but it needs to be cleaned every few years or it gets "cranky" in one way or another. When it's clean, it's great!

Good luck,

Steve

[Mike Self]

in a word, they weren't much good 25 years ago and haven't improved with age! Mine got to the point where I could make it run well with the choke on, or with the choke off, but not both. That precipitated a swap to a 32-36 Weber back around 1981. But to attempt troubleshooting yours...

No vacuum leaks that you know of, so I would suspect a choke that isn't pulling off all the way. On mine, the fast idle cam had teeth so badly worn that it wouldn't fast idle when cold--so it would stall. If I set the idle speed so that it wouldn't stall when cold it would idle at 1500 rpm warm. So...check the fast idle and the water choke enriching linkage to make sure the choke is coming completely off when the engine warms up. The fast idle rachet should be fully disengaged, and the choke plates in the carb throats should be fully opened.

One more potential vacuum problem to check: the secondary barrel vacuum capsule. It draws vacuum from inside the carb and will cause the second carb barrel to open (suddenly!) when the accelerator pedal is floored. If that diaphragm has a hole in it, it's a vacuum leak.

Let us know whatcha find.

mike

[cw549]

Wow thanks for all the advice and tips guys!! Really appreciate it.

Pulled of the carb, went through everything and cleaned it with compressed air and carb cleaner. Put it back together, fired it up... same problem. So i took a look at the electric idle bypass valve (according to haynes manual) i cleaned it out, and used some hi temp sealant around the threads and voila!! it idles like a charm at 700... how i missed that sound!!

Will let her run for a bit tomorrow to check everything. Thanks again for all the help everyone!

[dbmw2002]

Did anyone mention the electric idle stop solinoid? Can make these exact sympyoms if buggered

[pastellblau76]

hey guys

i'm rebuilding my original soles carb (dual/progressive) that's in my '76 2002. I'm having a hard time figuring out what jets it's supposed to have. I'm assuming the last owner put bigger jets to get more power and I'm having no luck finding out which size jets the primary should have. I would really appreciate your help

Thanks!

[Conserv]

5 hours ago, pastellblau76 said:

hey guys

i'm rebuilding my original soles carb (dual/progressive) that's in my '76 2002. I'm having a hard time figuring out what jets it's supposed to have. I'm assuming the last owner put bigger jets to get more power and I'm having no luck finding out which size jets the primary should have. I would really appreciate your help

Thanks!

 

Not to actually answer your question (beyond c.d.'s illustration above) -- sorry -- but why do you assume the jets were changed?  For the 2-barrel carbs, there were probably 50 Weber carb conversions for every Solex jet "upgrade".  In short, larger jets in a 2-barrel Solex are certainly possible, but it was somewhat unusual.

 

Regards,

 

Steve

[John76]

Do you have a California '76 with manual transmission?

If so, here is the list of jets for the original Solex 32/32 DIDTA carb....stock from the factory. I am the original owner, so I know this is true.

 

Main jet:                  122.5       125

Air Corrector:           130           80

Venturi:                      24           28

Idle jet:                      60           60

 

This recipe was for the CA Smog-strangled car....which ran poorly....even when new and properly tuned.

 

The European jet recipe was:

 

Main jet:                117.5       140

Air Corrector          120           90

 

I ordered these jets from my local dealer ($1.97 each in 1976) and the car ran a bit better. Smoother idle and no flat spots on acceleration.

 

However, the overall performance was still mediocre....so  I installed the Weber 32/36 DGEV (electric choke) when the 50K mile emissions warranty expired. What a difference! Easy to tune, maintenance free, and a small improvement on MPG.

Passed CA smog test every time during the last 90,000 miles. My '76 2002 now has 138,000 miles from new, and is ready to hit the road again after 19-years of "rest" in my garage.

 

John76

 

[fuzzyhead]

Subscribed.

My Solex is doing all kinds of strange things. Sputtering under heavy acceleration mostly, but now it wants to idle at 3,000 RPM.

[zinz]

Was it running well before?