DIY Manual Choke Conversion

Frequently asked technical questions and common modifications/improvements
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Tim Leech
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1980 Morris Marina 1.7HL DBV468W
1985 CITROEN BX 19GT C1TBX
1991 CITROEN BX 19TZI AUTO A/C TAL91S
1994 CITROEN XANTIA 1.8 SXi M908HRY
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DIY Manual Choke Conversion

Post by Tim Leech » Thu Dec 27, 2012 3:12 pm

Its well documented that the achilles heel of most carb fed BX's is the auto choke, I would be more than happy to replace both of mine for a cable affair, ive owned plenty of manual choke equipped cars (the SD1 has one and starts first time every time) surely it cant be that difficult as the 16RE has one.

Can anyone point me in the right direction of what to do, the 16TRS will be getting some use next year (and my be for sale) and the autochoke on that is rather hit and miss!

Cheers
1985 BX 19GT Mk1
1991 BX 19TZI Auto A/C
1994 Xantia 1.8i SX
1972 Morris Marina 1.8 SDL
1979 Rover SD1 V8-S
1980 Morris Marina 1.7HL
1998 Rover 75 2.0V6 Connoisseur Auto
2002 Rover 75 CDT Connossieur SE Nav
2002 Rover 45 1.6i Spirit S Special
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JayW
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Re: DIY Manual Choke Conversion

Post by JayW » Thu Dec 27, 2012 3:22 pm

I've literally JUST done it on the Athena (yesterday). I'll post up some pics shortly but it will mostly be determinied by the carb & linkage you have (although the principle remains the same).
I have zero patience for your tedium.

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JayW
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Re: DIY Manual Choke Conversion

Post by JayW » Thu Dec 27, 2012 4:18 pm

Finding a suitable choke KIT is like finding a shoeful of unobtainium so i had to make my own up from these components:

http://www.ebay.co.uk/itm/110978735890" onclick="window.open(this.href);return false;
http://www.ebay.co.uk/itm/300812373807" onclick="window.open(this.href);return false;
http://www.ebay.co.uk/itm/271097219060" onclick="window.open(this.href);return false;
Total cost £14.50 and couple of washers.

There may well be various linkages dependent on carb spec so i'll quote for the Weber and the Solex boys can adapt.

Just remove the waxstat from it's mount (along with any counter-spring), you can either remove it and hook the pipes together with a piece of tube OR (like i did) just cable tie it securely out of the way (without kinkying the hoses) so you have the option to reinstate it:

Image

Then, locate the adjuster (item 2 above) where the waxstat used to mount. On mine it was mounted in a bracket through large hole so i put the adjuster through a couple of penny-washers and loosly tighten it around its mid-point.

Mount the Choke Cable in the cabin and pass its end through the bonnet release grommet (just above the brake pedal), round the engine bay in a good wide arc to the Adjuster (avoiding contact with the alternator).

Image
Image

You should note that the inner of the cable is captive and only moves the distance the knob does and cannot be withdrawn from it's sheath, so don't be tempted to cut the cable down otherwise it'll be bin fodder.

Once passed through the Adjuster you simply have to connect it to the actuating arm the waxstat operated, in my case a small ID washer and trunion was all that was required. You should secure this when the cable is taut against the arm but not actually operating it.

Image

Then pull the knob to check you get sufficient operation and use the adjuster to correct if required. When complete, securely tighten the Adjusters nuts. Jobbed.

Now that's enough talk of knobs and nuts for one day! ;)
I have zero patience for your tedium.

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Re: DIY Manual Choke Conversion

Post by kiwi » Thu Dec 27, 2012 7:31 pm

NOw I have seen this I feel some cosmetic surgery coming on.
1991 BX19 TZS 04/01/91 (Deceased)
1990 BX19 TRS 27/10/89 (Reborn)
1992 BX19 TXD (Ex UK - K 744 SDF) 15/06/92
1990 BX19 TZS Auto 06/11/1989
1992 BX TZD Turbo Estate (Ex UK) 1/07/91

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Tim Leech
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My Cars: 1963 VW BEETLE 1200 KGJ413A
1972 Morris Marina 1.8 SDL BFA720L
1979 Rover SD1 3.5 V8-S ERC742T
1980 Morris Marina 1.7HL DBV468W
1985 CITROEN BX 19GT C1TBX
1991 CITROEN BX 19TZI AUTO A/C TAL91S
1994 CITROEN XANTIA 1.8 SXi M908HRY
1998 Rover 75 V6 Connoisseur Auto S392DEH
2002 Rover 75 CDT Connossieur SE Nav R40TSL
2003 Rover 25 1.6i XL L33CHT
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Re: DIY Manual Choke Conversion

Post by Tim Leech » Fri Dec 28, 2012 10:11 am

Excellent Jay, how is it running? much better I hope?
1985 BX 19GT Mk1
1991 BX 19TZI Auto A/C
1994 Xantia 1.8i SX
1972 Morris Marina 1.8 SDL
1979 Rover SD1 V8-S
1980 Morris Marina 1.7HL
1998 Rover 75 2.0V6 Connoisseur Auto
2002 Rover 75 CDT Connossieur SE Nav
2002 Rover 45 1.6i Spirit S Special
2003 Rover 25 1.6i XL 5 DR

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Tim Leech
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Joined: Tue Apr 15, 2008 11:12 am
Location: Burton on Trent
My Cars: 1963 VW BEETLE 1200 KGJ413A
1972 Morris Marina 1.8 SDL BFA720L
1979 Rover SD1 3.5 V8-S ERC742T
1980 Morris Marina 1.7HL DBV468W
1985 CITROEN BX 19GT C1TBX
1991 CITROEN BX 19TZI AUTO A/C TAL91S
1994 CITROEN XANTIA 1.8 SXi M908HRY
1998 Rover 75 V6 Connoisseur Auto S392DEH
2002 Rover 75 CDT Connossieur SE Nav R40TSL
2003 Rover 25 1.6i XL L33CHT
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Re: DIY Manual Choke Conversion

Post by Tim Leech » Fri Dec 28, 2012 10:13 am

Parts bought off fleabay, will get stuck in asap!
1985 BX 19GT Mk1
1991 BX 19TZI Auto A/C
1994 Xantia 1.8i SX
1972 Morris Marina 1.8 SDL
1979 Rover SD1 V8-S
1980 Morris Marina 1.7HL
1998 Rover 75 2.0V6 Connoisseur Auto
2002 Rover 75 CDT Connossieur SE Nav
2002 Rover 45 1.6i Spirit S Special
2003 Rover 25 1.6i XL 5 DR

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JayW
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Re: DIY Manual Choke Conversion

Post by JayW » Fri Dec 28, 2012 1:33 pm

Certainly better being controlable!
I have zero patience for your tedium.

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Tim Leech
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Joined: Tue Apr 15, 2008 11:12 am
Location: Burton on Trent
My Cars: 1963 VW BEETLE 1200 KGJ413A
1972 Morris Marina 1.8 SDL BFA720L
1979 Rover SD1 3.5 V8-S ERC742T
1980 Morris Marina 1.7HL DBV468W
1985 CITROEN BX 19GT C1TBX
1991 CITROEN BX 19TZI AUTO A/C TAL91S
1994 CITROEN XANTIA 1.8 SXi M908HRY
1998 Rover 75 V6 Connoisseur Auto S392DEH
2002 Rover 75 CDT Connossieur SE Nav R40TSL
2003 Rover 25 1.6i XL L33CHT
x 45

Re: DIY Manual Choke Conversion

Post by Tim Leech » Fri Dec 28, 2012 1:57 pm

Well if I can sort the starting and overfuelling issue for £15 then 2013 will be off to a good start!

Worth making this thread a sticky mods?
1985 BX 19GT Mk1
1991 BX 19TZI Auto A/C
1994 Xantia 1.8i SX
1972 Morris Marina 1.8 SDL
1979 Rover SD1 V8-S
1980 Morris Marina 1.7HL
1998 Rover 75 2.0V6 Connoisseur Auto
2002 Rover 75 CDT Connossieur SE Nav
2002 Rover 45 1.6i Spirit S Special
2003 Rover 25 1.6i XL 5 DR

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Re: DIY Manual Choke Conversion

Post by citsncycles » Fri Dec 28, 2012 2:48 pm

Nice installation, particularly as the choke knob is fitted where they are installed by Citroen on the 14's. All I'll say is that if the choke gets stiff, of you pull on it too enthusiastically the whole surround it's attached to can pop out of the dash!
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electrokid
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Re: DIY Manual Choke Conversion

Post by electrokid » Sat Dec 29, 2012 9:32 pm

IMHO when an auto choke starts playing up it's often not a problem with the auto choke itself - it's usually a symptom of something else starting to go wrong - so it's worth investigating. Converting to a manual choke gives one a sense of control over the situation but it may be covering up a developing problem.
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Re: DIY Manual Choke Conversion

Post by citronut » Sun Dec 30, 2012 12:52 pm

the usual failing of the auto choke used to be people/owners twiddling with the adjustment/settings,

the choke knob Jay has used looks like to old BMC style, you need to pop the lens out and replace the design for chevrons,

cant be having BMC bits on a citroen :roll: :wink:

regards malcolm
curent ride
K reg BX 17TD TZD est
also own
K reg D special

no longer have
H reg CX saffari 2.5 TRI (now gone to Malaysia)
R reg xantia 1.9TD est (gone to meet its maker)

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barry badger
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Re: DIY Manual Choke Conversion

Post by barry badger » Sun Dec 30, 2012 7:05 pm

I have to say i would regard fitting a manual choke as going backwards, i would sooner fix/adjust the auto choke.
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Re: DIY Manual Choke Conversion

Post by Mickey taker » Sun Dec 30, 2012 7:20 pm

If I still had the meteor I would be doing this as from personal experience, the solex autochoke is a worthless pile of poo imho
1991 BX Meteor 1.6

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JayW
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Re: DIY Manual Choke Conversion

Post by JayW » Sun Dec 30, 2012 7:47 pm

barry badger wrote:i would sooner fix/adjust the auto choke.
In my case, there's nothing wrong with the autochoke, it operates perfectly. The problem is with the waxstat & linkage.

One of the previous owners of my car changed the carb to a similar (but not identical) Weber. This came with a different linkage and although for the purposes of the throttle cable it is identical, the autochoke linkage is different.

Where many waxstats are physically identical, the "throw" of the wax cartridge and length of the pin are different. In this case, the pin is too long and operates the choke too far (2500rpm) at it's minimum adjustment. I removed the pin to cut it down and lost it on the gravel driveway. :?

My manual choke is fitted while I wait to bother to find a suitable replacement. And as a 20 minute job it was hardly a massive undertaking.

My driving is mostly short commutes and now i have manual control I find i can turn the choke off much sooner than the auto choke with no detrimental effect as the start of most of my journey are long downhill gradients. This means less fuel for approximately 10% of my daily mileage. Which has got to be worth a 2 mpg saving off my (remarkably) consistent weekly MPG.

I gained 3mpg in the week the choke was completely disconnected after losing the pin. But as we all know, cold and lean is mean :wink: Hence i had to fit the manual.

Time will tell.
I have zero patience for your tedium.

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Tim Leech
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Joined: Tue Apr 15, 2008 11:12 am
Location: Burton on Trent
My Cars: 1963 VW BEETLE 1200 KGJ413A
1972 Morris Marina 1.8 SDL BFA720L
1979 Rover SD1 3.5 V8-S ERC742T
1980 Morris Marina 1.7HL DBV468W
1985 CITROEN BX 19GT C1TBX
1991 CITROEN BX 19TZI AUTO A/C TAL91S
1994 CITROEN XANTIA 1.8 SXi M908HRY
1998 Rover 75 V6 Connoisseur Auto S392DEH
2002 Rover 75 CDT Connossieur SE Nav R40TSL
2003 Rover 25 1.6i XL L33CHT
x 45

Re: DIY Manual Choke Conversion

Post by Tim Leech » Mon Dec 31, 2012 4:07 pm

Mickey taker wrote:If I still had the meteor I would be doing this as from personal experience, the solex autochoke is a worthless pile of poo imho

I've got a solex on WTF, which is a pain, strangely the GT is fine
1985 BX 19GT Mk1
1991 BX 19TZI Auto A/C
1994 Xantia 1.8i SX
1972 Morris Marina 1.8 SDL
1979 Rover SD1 V8-S
1980 Morris Marina 1.7HL
1998 Rover 75 2.0V6 Connoisseur Auto
2002 Rover 75 CDT Connossieur SE Nav
2002 Rover 45 1.6i Spirit S Special
2003 Rover 25 1.6i XL 5 DR