Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
What do British people call the choke on a carburetor? I found a translation that showed the British use of "choke" to be what an American would call a "barrel" of a carburetor, but what do British folks call the flap at the top of the carb that reduces airflow to richen the fuel mixture for starting a cold engine?
Location: East of Seattle since 1992, 615' Elevation, Zone 8b - originally from SF Bay Area
44,551 posts, read 81,085,957 times
Reputation: 57728
I had a friend from the UK years ago and did a lot of work on his Morris Minor. It was fun to learn some of their terms other than the commonly known boot and bonnet. His car did have a manual choke, and he always called it a choke. I do know that they refer to carburetors as 1, 2 or 4 "Choke" or "Venturi" rather than barrel.
have heard this starting device by the British referred to as either:
1) a "strangler"
2) "cold starting enrichment" to be used as needed for starting the engine when cold.
For real?
Were they having you on because you're an American and asked?
Was the engine a carb, or some other form of fuel delivery? (Injection technically doesn't need a choke, you just increase fuel delivery for starting)
Born and raised British, lots of experience getting dirty on engines of bikes and cars, for both road and track.
I call it a choke, and as far as I know pretty much everyone else does to.
The issue I think is that double choke and double barrel are synonymous, a double choke carb is a double barrel carb, (the carb has two barrels and two chokes) but double barrel is also a colloquialism for a shotgun, so double choke is more parlance for the term double barrel in the US.
Even SU carbs (that don't have a traditional butterfly restrictor on the air intake above the jet) have "chokes".
I'm trying to remember what's written on the choke pull knob on my 1972 MG-B's dash. I have looked at it 1000 times, but right now can't recall what it says.
I have read the term "strangler" used to mean "choke" in older British publications about cars and bikes, but can't recall a specific issue of a specific magazine. Some Brit bikes use a "tickler", a device to manually depress the float in order to intentionally (slightly) flood the carb as an alternative to a choke. I think Harleys, older ones with carbs, use a choke, as do Guzzis, I forget what BMW did on the Bing carbs. Most all Japanese bikes use an auxiliary jet to allow a richer starting mixture instead of using a conventional choke to increase the vacuum signal to the running jets. No idea what the advantages and disadvantages of all these systems are, except that the "tickler" probably is cheaper to make than other alternatives.
I actually like the older machines better *because* they are harder to start, harder to drive. The difference between a skilled operator and a duffer is stark. Now, a rich kid or just a kid with some credit can buy a bike or car that is so damn easy to run, with so much power, and such sophisticated electronic "nannies" to save them when they attempt to break Newton's laws, that these drivers are damn near just along for the ride, "R2D2" is actually doing all the real driving.
I'm trying to remember what's written on the choke pull knob on my 1972 MG-B's dash. I have looked at it 1000 times, but right now can't recall what it says.
If it's original it'll have a four leaf clover kind of shape (or four pieces of pie) with "lock" curved on the top of the knob (because you could lock it on pull out by giving it a partial turn).
If it's not original it's probably got a C on it, or choke.
95% of the MGBs were sold in the US and Canada. A lot of old English terminology has been displaced by American.
They called a fender a mudwing, a bumper was a fender, windshield was a windscreen, a starting handle was a hand crank, an estate car was a station wagon, a drophead coupe was a convertible, etc, etc.
Were they having you on because you're an American and asked?
Was the engine a carb, or some other form of fuel delivery? (Injection technically doesn't need a choke, you just increase fuel delivery for starting)
Born and raised British, lots of experience getting dirty on engines of bikes and cars, for both road and track.
I call it a choke, and as far as I know pretty much everyone else does to.
The issue I think is that double choke and double barrel are synonymous, a double choke carb is a double barrel carb, (the carb has two barrels and two chokes) but double barrel is also a colloquialism for a shotgun, so double choke is more parlance for the term double barrel in the US.
Even SU carbs (that don't have a traditional butterfly restrictor on the air intake above the jet) have "chokes".
So a choke is a choke in the US and UK.
Sorry, Gungnir ... but back in the 1960-70's a shop next to mine was a Brit car specialty shop/boneyard owned/operated by a bunch of expats. For a time, they were the area big deal "go-to" shop for Jags, Triumphs, MG's ... and while friendly to work with most of the time, they couldn't understand how my little "no-name" shop got RR's, Bentley's, Aston Martin's, Lotus, Jags, A-H's, Morgan's, and an odd Riley or Lanchester in the door when they were the real "experts" in Brit cars of the day. It really hacked them off when I got a fleet of Brit double-decker buses for a client (a bar owner in Denver used them as a promo or for special events) ... they couldn't understand how I could work on the cars and the diesels (leyland and bristol), too.
They were my source for a lot of the terminology ... y'know, stuff like "boot" and "bonnet", and my wrenches were "spanners". They used to drool over my tool collection of Whitworth and BS sockets ... my stuff was all snap-on/hazet/dowidat ... theirs was all King Dick (which they used to sell over the counter to the DIY'ers). K-D was cheap even for infrequent use tooling, but they sold a lot of it to Brit bike and car owners who could bung up the fasteners before returning to the shop for professional assistance.
I did a fair amount of biz with Moss Motors back then, and bought a Weber side-draft carb kit for ... well, if memory serves me, it's a long time ago ... a TR engine in a Morgan 4+4 that we were doing an engine overhaul/upgrade (displacement increase) and performance upgrade. The kit was a Brit package with the new intake manifold. I do recall that the choke butterfly function was referred to in the instruction pages as a "strangler".
Not the first time I'd heard the term, I'd heard it referred that way in a couple of the older BSA, Matchless, Ariel, and Norton owner's manuals that I had acquired with bikes through the years. I recall seeing the term in an Amal carb service manual, too.
Please note that nowhere did I refer to the need to use a "choke" device in any fuel injected vehicle. You and I both know that such function is automatic on most cars via the control circuits for the respective FI system, be it mechanical or electronic with engine temp sensors, intake air temp sensors, and so forth.
With two notable exceptions I've run into ... SPICA mechanical FI as used on of Alfa-Romeo ... where the thermostatic control on the injection pump could frequently be wildly out of touch with the requirements of the engine for a start (cold or warm). The "best" solution I've ever found was to install the manual enrichment cable mod on these so that the driver could manually select the fuel enrichment. As well, the Bosch mechanical FI system on 'benz 300SL's had a cold starting enrichment knob on the dash; pulled out to start the car. Later versions of that mechanical injection system on 'benz's used a small T-stat fitted on the injection pump linked to a fuel enrichment circuit and fast idle air slide for the start and warm-up cycle. While not a common failure item, I've replaced many on older 220/250/280 in-line 'benz 6-cylinder cars with starting/cold running problems that weren't diagnosed by other shops in my area.
SU's (Skinner's Union, for those who'd like to know ... their original product dated back to making leather diaphragms for carbs) fuel enrichment circuit for cold starting was interesting. By lowering the main jet from it's normal running position, it allowed more fuel to flow up the main jet needle in the center below the airslide. A fuel enrichment circuit rather than a "choke" in the mechanical sense.
I'd also mention that not all "two-barrel" or "double-barrel" carbs use a mechanical choke butterfly to restrict air flow for cold start fuel enrichment on both barrels. Many two-barrel Weber carbs, for example, only use the butterfly on the "primary" barrel for cold starting, especially on the models where the secondary barrel is vacuum operated rather than mechanically linked for the throttle plate opening. Solex would be another carb manufacturer with a similar cold-start enrichment choke set-up.
I have read the term "strangler" used to mean "choke" in older British publications about cars and bikes, but can't recall a specific issue of a specific magazine.
Some Brit bikes use a "tickler", a device to manually depress the float in order to intentionally (slightly) flood the carb as an alternative to a choke.
AMAL carbs ... most common on Brit bikes you'd likely be familiar with, particularly with the "monobloc" (float chamber cast integrally with the slide/mixing chamber rather than the earlier series float chamber separate from the mixing chamber), or even the later "concentric" carbs ... all had a "tickler" to depress the float to allow a higher level of fuel in the float chamber. Both series of AMAL carbs had a mechanical slide plate inside the cylindrical airslide in the venturi which dropped down via a handlebar control cable for the cold start fuel enrichment function.
I think Harleys, older ones with carbs, use a choke, as do Guzzis, I forget what BMW did on the Bing carbs.
Old H-D's used domestic made carbs with a conventional choke butterfly plate. They switched to Keihin's, which use an aux fuel circuit and an accelerator pump to deliver more fuel for start up and warm up running.
Guzzi used a choke plate on their smaller singles and V-7's with the round body Dell'Orto carbs. D'O's were commonly used on numerous Italian built bikes. Guzzi changed to the "square slide" D'O's beginning with the Ambassador 750's, and on these carbs, the fuel enrichment for cold starting is an aux fuel delivery circuit ... and much appreciated for consistent fuel delivery compared to the old mechanical slide method of fuel enrichment for cold starting. Many's a cold morning when I need to use the aux fuel circuit on my Ambo, Eldo, or T-3 for start and warm-up running for the first several minutes of riding. Far superior consistent fuel delivery compared to guessing with a tickler and mechanical air slide. Guzzi's tend to cool the carb airflow so much during warm-up riding that you can see moisture condense on the outside of the carb's.
Older BMW's with Bing's used a mechanical plate choke in the slide, similar to the AMAL carbs.
Most all Japanese bikes use an auxiliary jet to allow a richer starting mixture instead of using a conventional choke to increase the vacuum signal to the running jets. No idea what the advantages and disadvantages of all these systems are, except that the "tickler" probably is cheaper to make than other alternatives.
the tickler was an inconsistent device for fuel enrichment. You'll see a lot of riders punch the button repeatedly without realizing that all they're doing is pushing the float down and allowing the fuel needle to come off it's seat to get a higher level of fuel in the float chamber. Far better for consistency in starting is to depress the tickler button once, holding it down for a number of seconds (best to count the seconds ... one thousand, two thousand, etc). I could start my Ducati Mach 1 (and many other 250/350 Duck's reliably by holding down the tickler for a 3-count on a 60-70 degree morning start ... but 40 degree morning's needed a 5-second count. Never used the choke on these bikes, "flooding" the carb via the tickler was all they needed. Far different than the AMAL carbs on the Brit bikes where tickling for a few seconds and using the choke was needed for a start and cold run cycle.
The tickler was simpler and less expensive than an aux fuel circuit ... but with the drawback of inconsistent results and ability to deliver an enriched fuel mixture for cold running. The big advantage of the aux fuel circuit is that most of the carbs using same are far more precise in their fuel metering than the older carb designs ... allowing for better mixture control, fuel economy, performance, and lower emissions.
I used to use an exhaust gas analyzer on all carb adjustments. While the AMAL's (and SU's) were relatively crude ... and you could "tune" them by ear with the little tricks of dialing them in to sound OK and then pick up the airslide ever so slightly to hear the engine response ... it was far quicker and simpler to dial them in to my known basic settings and double check with a drive. Weber carbs in good condition were like dialing in a fuel injection system. Solex's were pretty decent, too. Same thing for Dell Ortos, far better to dial them in at idle speeds (assuming correct jets per manufacturer spec and float levels properly adjusted) with the 2-gas analyzer than to mess around with approximate adjustments.
Even in the 1960's ... Sun had a CO exhaust gas analyzer which was pretty effective in the shop for tuning. My "ace in the hole" was a Montgomery Wards portable single gas analyzer (bought in 1965) that had a tailpipe probe and a strap-on the vehicle sensor unit that read out on a remote indicator you could hold in your hand or set on a dash. I could get reasonable CO/mixture readings on my road tests on bikes and cars with this unit ... a portable tuning "dyno" for test drives. 1970's 2-gas analyzers were an improvement ... I was one of the first shops in the area to use one until Colorado started requiring emissions testing on the Front Range counties and the shops had to buy one for the test program. At that, however, many shops didn't use the test equipment for tuning purposes, only to verify and dial in for emissions compliance ... which at the time was pretty lax at 4.5% max CO/400ppm Hydrocarbons.
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.
Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
