Spring thingy that controls choke

Pirate Lady

Well-Known Member
Jun 2, 2020
7,574
Chesapeake Bay, Middle River
Boat Info
Sundancer 250 ‘91
Engines
7.4 Bravo 1
Rochester Quadrajet vacuum choke. Spring thing controls choke. All at marina know what it does but nobody knows it’s name. Need order this part. Know what it is? See picture. that thing to the right of the bolt.
Choke spring part.jpg
 
Rochester Quadrajet vacuum choke. Spring thing controls choke. All at marina know what it does but nobody knows it’s name. Need order this part. Know what it is? See picture. that thing to the right of the bolt.View attachment 92434

Can't tell from your pic, but if you have a vacuum pull off it should open the choke butterfly slightly, immediately after it starts and is adjustable.
 
pull off it should open the choke butterfly slightly
at rest (before starting) the choke plate is slighty open causing hard starting, when i manually hold it closed all the way it fires right up.
and thanks for the name identification.
 
Mitch ,
this is the carb looks like when engine cold just before trying to start. its open, hold closed manually and it starts easy. Now i just have to convince the wife to get down in the engine and hold it closed until i can fix it.
 

Attachments

  • Carberator.jpg
    Carberator.jpg
    36.1 KB · Views: 72
Mitch ,
this is the carb looks like when engine cold just before trying to start. its open, hold closed manually and it starts easy. Now i just have to convince the wife to get down in the engine and hold it closed until i can fix it.
Is that what it looks like AFTER you pump the throttle at least once?

Make sure the fast idle cam linkage moves freely. If that is sticking, it could prevent the choke plate from fully closing.
 
nope, thats what it looks like before i touch anything. took off the flame arrestor, and took the picture.
fast idle cam linkage moves freely
now this is interesting. i dont have a fast idle (like in a car where it auto adjusts and then goes down as warms up). I have to control all idle speed with the throttle.
 
When a warm engine cools down, the choke will close most of the way. You usually need to open the throttle to release pressure on the linkage to allow the plate to fully close.
 
You say that the fast idle linkage moves freely but don’t have a “fast idle” on cold start?

Are you missing the fast idle adjustment screw?

There is usually an adjustment screw that rests on the fast idle cam that you can turn to raise or lower your fast idle speed. Once the engine warms up and the choke is fully opened, the fast idle cam should drop out of the way of the fast idle screw.
 
Chokes on a boat? Never could quite figure that out.
Originally installed on automobiles for cold weather, like snowing cold which is not boating weather.
I have always in-op’ed the chokes on my boats.
Pump the throttle 2-3 times, leave open 10-20% and crank.
fires every time on an engine with a decent tune. Oh
 
Wanderer,
i tend to agree with you in theory, but even my little dinghy outboard needs the choke applied when motor is 'cold' on a 90 degree day or i can pull the cord all day and no start. and its very in tune, brand new.
 
A smaller displacement engine , a few cubic inches, would need a choke given that it does not have a mechanical fuel pump, move nearly the cfm a larger v8 does and typically does not have an accelerator pump.
Anyhow, my theory worked in practice for approximately 30 years until I got a boat with efi...
 
i took a picture of my part and one i found on the internet. ALL the ones on the internet are like this one pictured; but it's backward from mine. Mine has the part for the screw to mount on the side facing the carb with the spring loop for the lever on the right (you can tell because the opening of the cover plate is on the right). ALL the ones i find on the internet have the spring loop on the left. If anyone has this setup and can look at yours and reply about this I sure would appreciate it. i cant understand why mine seems to be ass-backward from every single one i can find for sale on the net.

Choke spring mine.jpg
choke spring - internet.gif
 
Pump the throttle 2-3 times, leave open 10-20% and crank.
wanderer,
you saved me about $700+, i went to boat today, and did what you said, and it fired right up. i must have been flooding it. i did this and boat started so easy. i dont need carb rebuild or choke repair (so it seems). i wasnt starting it the right way.
 
i still may pursue the choke spring thing if i can see another on a boat and watch it work, but for now i am good. there seems to be slack in that spring before it starts moving the lever to operate choke, so maybe its a little worn out.
 
Better yet! Next time you need a carb rebuild, think about spending a little extra and getting yourself a new carb with an electric choke instead. Edelbrock 1409 with an adapter plate has worked well for me several times in the past.
 

Forum statistics

Threads
112,946
Messages
1,422,785
Members
60,930
Latest member
Ebrown69
Back
Top