Manual choke....
Discussion
I learned to drive in my mum's 2 year old Mk3 Astra and, once I'd passed, felt I couldn't afford to buy and run my own car so used the 96P Corsa that replaced it, the 99V Corsa that replaced that, and my Dad's 99T Fiesta Zetec for a little while.
At 22 I'd left Uni and saved enough to buy my first car. Ended up being a 90H 205 Roland Garros. The manual choke was one of a number of things that made me immediately think I'd made a terrible mistake when I first drove it on my own! But, needless to say, it soon became second nature.
I loved that car.
As said earlier on in the thread, hot starting was more of an issue for it. Near the end of my time with it I'd have to park it facing downhill. Looked a bit odd as I was an Estate Agent by then and could sometimes end up parking miles away from a house I was showing!
At 22 I'd left Uni and saved enough to buy my first car. Ended up being a 90H 205 Roland Garros. The manual choke was one of a number of things that made me immediately think I'd made a terrible mistake when I first drove it on my own! But, needless to say, it soon became second nature.
I loved that car.
As said earlier on in the thread, hot starting was more of an issue for it. Near the end of my time with it I'd have to park it facing downhill. Looked a bit odd as I was an Estate Agent by then and could sometimes end up parking miles away from a house I was showing!
Flooble said:
I'm guessing you have an accelerator pump so when you pump the throttle it is acting like a primer adding fuel straight into the cylinders.
Yep. The twin SUs fitted as standard were giving me all kinds of grief a few years back, so I installed a Weber 32/36 with manual choke (DGV).Still got the SUs in my garage and I'll re-build them one day... or stick a set of Weber 45's on to match the cam & headwork I have planned at some point.
I've just remembered my last carb fed car had an auto choke that would sometimes stick on after the engine had warmed up, this would result in an idle speed of about 3k rpm, it was a Sierra with a tuned 2.8 v6 so it was sometimes a bit of a surprise when you wanted to slow down only to find that the engine was still revving it nuts off...
M1C said:
Holy thread ressurection!
I was just discussing manual chokes with a mate (as you do....) and i recalled that my first car had one, a 1988/9 Renault 5 1.2.
At the time i probably wasn't bothered but i look back on it now fondly...a quaint feature.
It required a bit of skill to get right!
Unless it was an especially mild/warm morning, it would need at least some choke every day to get started - and full choke on anything like a cold day or winter.
Then you had to adjust it as you went along....you couldn't simply close it in one go...it would need to be carefully reduced you you went long.
Then of course - you'd be able to tell the difference between running too lean and too rich....one would see the engine trying to cut out....and the other would get that....munchy munchy feeling (technical description there) and also trying to cut out.
Another feature of the choke...at least on my Renault 5....was if you were driving at 60mph, you could pull the choke out fully....and.....voila... rudimentary cruise control! Didn't do that very often though....
Then i had a 1993 Fiesta 1.1 which had an automatic choke...and you could feal (and hear) it working...you could feel things changing as you drove along...and you could tell when it closed it fully....normal service would be resumed.
Rose tinted spectacles? Probably, yes.
I use cruise control mode on my 86 Nova Antibes! Felt really bizarre when I first discovered this function! Probably not the best for economy though!I was just discussing manual chokes with a mate (as you do....) and i recalled that my first car had one, a 1988/9 Renault 5 1.2.
At the time i probably wasn't bothered but i look back on it now fondly...a quaint feature.
It required a bit of skill to get right!
Unless it was an especially mild/warm morning, it would need at least some choke every day to get started - and full choke on anything like a cold day or winter.
Then you had to adjust it as you went along....you couldn't simply close it in one go...it would need to be carefully reduced you you went long.
Then of course - you'd be able to tell the difference between running too lean and too rich....one would see the engine trying to cut out....and the other would get that....munchy munchy feeling (technical description there) and also trying to cut out.
Another feature of the choke...at least on my Renault 5....was if you were driving at 60mph, you could pull the choke out fully....and.....voila... rudimentary cruise control! Didn't do that very often though....
Then i had a 1993 Fiesta 1.1 which had an automatic choke...and you could feal (and hear) it working...you could feel things changing as you drove along...and you could tell when it closed it fully....normal service would be resumed.
Rose tinted spectacles? Probably, yes.
DonkeyApple said:
I vaguely recall a mini I had would run on quite happily after turning the ignition off and the main use of the choke was to stop it.
Yes, pre-ignition or dieseling caused by glowing coke in the cylinders or some other hot part. Became a thing of the past since the arrival of electronic fuel injection. 
Had a mk3 Fiesta 1.0 H reg with a manual choke.
Even on the coldest days it would start first time. Warm days I would often start without it.
Car was so basic and easy to work on. Drove 5 miles with no water after a pipe split engine temperature off the red. Head gasket went so next day we changed it ourselves only took about 1hr. Rust got it in the end.
Even on the coldest days it would start first time. Warm days I would often start without it.
Car was so basic and easy to work on. Drove 5 miles with no water after a pipe split engine temperature off the red. Head gasket went so next day we changed it ourselves only took about 1hr. Rust got it in the end.
Recall as a 17 year old apprentice, driving a vauxhall cavalier down to just outside London from Birmingham, to another dealer, and my drive home was a Marina, pulled choke to start, and drove away, forgot about it until I pulled off the M6 in brum and the engine nearly dies from over fuelling, I'd left it out all the way up the M1 and M6 ...wonder what the MPG was?
Drove one to work this week!
The correct answer is based on the precise type you have. One of mine has Weber sidedrafts, and the choke is simply a jet that dumps humungous quantities of fuel into the cylinders. Full choke is always too much, 3/4 choke is about right on a cold day. Start to wind it in when the idle revs start to rise uncontrollably, and keep reducing it to manage the idle down. Once driving normally, all the way in.
The other car has an Edelbrock 4 barrel downdraft. The choke has two aspects - a dirty great flap that completely blocks the intake so that the vacuum is vast, and a small cam that lifts the idle and stops it stalling. Starting it requires 3 presses on the accelerator that shoots petrol into the thing. Then start it, as soon as it is running, push the choke in enough to open the flap, otherwise you will die of CO poisoning and the engine will stall. Wind the idle cam in as the engine warms up to maintain a sensible idle.
If you grew up with these things, you can still hear them working in modern cars because the ECUs are doing exactly the same things, just with a bit more precision.
The correct answer is based on the precise type you have. One of mine has Weber sidedrafts, and the choke is simply a jet that dumps humungous quantities of fuel into the cylinders. Full choke is always too much, 3/4 choke is about right on a cold day. Start to wind it in when the idle revs start to rise uncontrollably, and keep reducing it to manage the idle down. Once driving normally, all the way in.
The other car has an Edelbrock 4 barrel downdraft. The choke has two aspects - a dirty great flap that completely blocks the intake so that the vacuum is vast, and a small cam that lifts the idle and stops it stalling. Starting it requires 3 presses on the accelerator that shoots petrol into the thing. Then start it, as soon as it is running, push the choke in enough to open the flap, otherwise you will die of CO poisoning and the engine will stall. Wind the idle cam in as the engine warms up to maintain a sensible idle.
If you grew up with these things, you can still hear them working in modern cars because the ECUs are doing exactly the same things, just with a bit more precision.
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