BX 19GT PROBLEM NO MORE!

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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 TSL 982
1980 Morris Marina 1.7HL DBV468W
1985 CITROEN BX 19GT C1TBX
1991 CITROEN BX 19TZI AUTO A/C BXi 19
1994 CITROEN XANTIA 1.8 SXi M908HRY
2002 Rover 75 CDT Connossieur SE Nav Auto R40TSL
2003 Rover 25 1.6i XL L33CHT
x 70

BX 19GT PROBLEM NO MORE!

Post by Tim Leech » Sun Feb 14, 2016 2:45 pm

Hi Guys

The normally totally reliable MK1 GT had developed an issue whilst being in storage

It starts ok from cold as usual but when it warms up and the auto choke comes off it dies the minute I touch the throttle, if I don't touch the throttle it will idle ok.

It then wont start although tries to fire and blows back and spits flames out of the carb! If I leave it overnight to cool it starts up ok.

I've replaced the fuel filter, it has plenty of petrol.

Carb or ignition problem?
Last edited by Tim Leech on Sun Apr 17, 2016 7:57 pm, edited 1 time in total.
1963 VW BEETLE 1200
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
2002 Rover 75 CDTi Connossieur SE AUTO Nav
2003 Rover 25 1.6i XL 5 DR

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Kitch
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Re: BX 19GT PROBLEMS

Post by Kitch » Sun Feb 14, 2016 2:52 pm

Carb problem. Possible the main jets are blocked up slightly. Best thing is to strip it and rebuild it (or get someone to do it for you).

I'm no expert on carbs, but I know it's easier to just rebuild the thing then to faff around trying to work out what's wrong. Solex Z1 kits are easily available, I've just done one on the AX GT (pretty much the same carb).

mds141
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Re: BX 19GT PROBLEMS

Post by mds141 » Sun Feb 14, 2016 3:25 pm

Is it still running the Solex carb? A Weber replacement is available and they tend to be more reliable.
Mark Smith

Is it just me or is everything shit?

1989 BX GTi 16 valve. Blanc Alpine. Completed the Citroen Classic Challenge Ecosse and 1337 miles without a hitch.
2000 XM VSX 2.1 td Auto. Rouge Magenta.
TGD saloon many years ago.

1990 Swift 'Corniche' 12/2 aka BXClub HQ.
Honda Firestorm. Gone, but not forgotten.
2015 Triumph Tiger Explorer XC.

mds141
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Re: BX 19GT PROBLEMS

Post by mds141 » Sun Feb 14, 2016 3:27 pm

The fuel will have gone off from being in storage and the jets might have become gummed up. When modern petrol evaporates it leaves behind a kind of varnish which causes umpteen problems with carbs. You can buy fuel stabilisers for vehicles which are used infrequently.
Mark Smith

Is it just me or is everything shit?

1989 BX GTi 16 valve. Blanc Alpine. Completed the Citroen Classic Challenge Ecosse and 1337 miles without a hitch.
2000 XM VSX 2.1 td Auto. Rouge Magenta.
TGD saloon many years ago.

1990 Swift 'Corniche' 12/2 aka BXClub HQ.
Honda Firestorm. Gone, but not forgotten.
2015 Triumph Tiger Explorer XC.

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Kitch
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Re: BX 19GT PROBLEMS

Post by Kitch » Sun Feb 14, 2016 3:58 pm

Solexes are fine if they're set up properly, to be fair.

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Tim Leech
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Posts: 15201
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 TSL 982
1980 Morris Marina 1.7HL DBV468W
1985 CITROEN BX 19GT C1TBX
1991 CITROEN BX 19TZI AUTO A/C BXi 19
1994 CITROEN XANTIA 1.8 SXi M908HRY
2002 Rover 75 CDT Connossieur SE Nav Auto R40TSL
2003 Rover 25 1.6i XL L33CHT
x 70

Re: BX 19GT PROBLEMS

Post by Tim Leech » Sun Feb 14, 2016 5:05 pm

The carb on this has been spot on for 8 years and starts well, I do have a spare weber but would prefer to stick with the original,

Is it worth giving it a good blast with Sold carb cleaner? A rebuild is not a problem,
1963 VW BEETLE 1200
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
2002 Rover 75 CDTi Connossieur SE AUTO Nav
2003 Rover 25 1.6i XL 5 DR

mds141
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Re: BX 19GT PROBLEMS

Post by mds141 » Sun Feb 14, 2016 8:59 pm

How much fuel is in the tank Tim? Might be worth chucking some Millers Ecomax fuel treatment in the tank and going for a longish run out. If that doesn't improve matters then a carb rebuild and set up. Cheaper option first.
Mark Smith

Is it just me or is everything shit?

1989 BX GTi 16 valve. Blanc Alpine. Completed the Citroen Classic Challenge Ecosse and 1337 miles without a hitch.
2000 XM VSX 2.1 td Auto. Rouge Magenta.
TGD saloon many years ago.

1990 Swift 'Corniche' 12/2 aka BXClub HQ.
Honda Firestorm. Gone, but not forgotten.
2015 Triumph Tiger Explorer XC.

mds141
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Re: BX 19GT PROBLEMS

Post by mds141 » Sun Feb 14, 2016 9:00 pm

Is the auto choke disengaging I wonder? If it's staying on, then over fuelling could be causing it to cut out when the throttle is applied.
Mark Smith

Is it just me or is everything shit?

1989 BX GTi 16 valve. Blanc Alpine. Completed the Citroen Classic Challenge Ecosse and 1337 miles without a hitch.
2000 XM VSX 2.1 td Auto. Rouge Magenta.
TGD saloon many years ago.

1990 Swift 'Corniche' 12/2 aka BXClub HQ.
Honda Firestorm. Gone, but not forgotten.
2015 Triumph Tiger Explorer XC.

Tinkley
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Re: BX 19GT PROBLEMS

Post by Tinkley » Sun Feb 14, 2016 9:01 pm

The Solex is OK. However when they are old some things deteriorate, namely the rubber/polymer parts in the carb. Best thing is the full seal kit which are stil available. You will NOT be able to change one part of the autochoke mechanism without breaking it, (not seen a replacement for this part btw), so leave this bit alone, however the diaghram withe the long L shaped metal rod is fairly critcal to getting the autochoke to work properly. I'd put money on yours being mighty stiff compared to a new part. Often this is most likely the only part you'll need to change.
Properly stripping the carb is pretty easy and all the passageways will blow clean with carb cleaner. Be careful with the diaghram in the accelerator pump ie note orientation, which face is the inner and don't lose the spring inside... so take off carefully. It may also be worth squeezing out the autocjoke waxstat working it to and fro and refitting. There is considerable spring pressure on this btw so be careful.. :wink:

Check the float weight it should be as per the manual 7 grams I think. If it is more chaneg the float, they become marginally heavy over time and don't work right if over 7.5 grams. Note you won't see petrol inside probably but it can still mean the plastic has started to absorb petrol in it's own grain structure.

Personally I'd also check the coil by substitution and maybe the ignition module, main earth, plus the exhaust manifold to down pipe gasket and spring strength after my recent experience with the auto. I'm assuming plugs, leads dizzy etc are all OK, sometimes a little corrosion on one of the contacts in the dizzy can be a big problem as can the main coil to dizzy HT lead. Pull all leads gently and inspect ends for corrosion.

You'll nail it Tim. Most of this stuff is pretty simple tbh, though really getting the carb fine tuned is a bit more tricky. Also you are right what seems like a carb problem often can be something else but at least if you go through it, generally you can eliminate each possible cause.

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ken newbold
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Re: BX 19GT PROBLEMS

Post by ken newbold » Sun Feb 14, 2016 10:30 pm

Only problem we ever had with our petrol BX was the distribution cap, the contacts on the underside got a build up of nasty crud, especially in the winter. A quick clean up and it was fine. Might be worth having a look in there
They think it's all over, it is now!

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Tim Leech
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Posts: 15201
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 TSL 982
1980 Morris Marina 1.7HL DBV468W
1985 CITROEN BX 19GT C1TBX
1991 CITROEN BX 19TZI AUTO A/C BXi 19
1994 CITROEN XANTIA 1.8 SXi M908HRY
2002 Rover 75 CDT Connossieur SE Nav Auto R40TSL
2003 Rover 25 1.6i XL L33CHT
x 70

Re: BX 19GT PROBLEMS

Post by Tim Leech » Mon Feb 15, 2016 1:15 pm

The auto choke is disengaging but I cant drive the car as when I touch the throttle it dies, I doubt its ignition related or surely it would do it all the time.
1963 VW BEETLE 1200
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
2002 Rover 75 CDTi Connossieur SE AUTO Nav
2003 Rover 25 1.6i XL 5 DR

Tinkley
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Re: BX 19GT PROBLEMS

Post by Tinkley » Mon Feb 15, 2016 5:05 pm

Not if the coil is failing, it will stall just as you try to pull away....ie max load. Had 2 go on the 14 and one on the 16. Our C4 has also just done the coilpack.... :wink: The 16/19 type will carry on working, though to be irritating if you let it get cold it will fire straight away!. If you have the gear it can be tested but you will find it may be out of range - capacitors tend to do this, or fail utterly.
But most likely the bottom of hte float is cruddy and a good clean will sort it. If there is a lot of rust in the float debris, suspect the steel fuel pipes, these also can leave a light petrol vapour a little above what you might expect if they are beginning to weep slightly.

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ken newbold
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Re: BX 19GT PROBLEMS

Post by ken newbold » Mon Feb 15, 2016 7:48 pm

Tim Leech wrote:The auto choke is disengaging but I cant drive the car as when I touch the throttle it dies, I doubt its ignition related or surely it would do it all the time.
Not necessarily, when it's ticking over there is very little load on it. So easy to check it out, have a look and see!
They think it's all over, it is now!

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Tim Leech
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Posts: 15201
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 TSL 982
1980 Morris Marina 1.7HL DBV468W
1985 CITROEN BX 19GT C1TBX
1991 CITROEN BX 19TZI AUTO A/C BXi 19
1994 CITROEN XANTIA 1.8 SXi M908HRY
2002 Rover 75 CDT Connossieur SE Nav Auto R40TSL
2003 Rover 25 1.6i XL L33CHT
x 70

Re: BX 19GT PROBLEMS

Post by Tim Leech » Mon Feb 15, 2016 8:22 pm

New coil ordered! Just in case.

I've spent very little on the GT mechanically so she's due some TLC. Plugs, fuel pump and filter, lhm change and some fresh oil.....ready for Holland!
1963 VW BEETLE 1200
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
2002 Rover 75 CDTi Connossieur SE AUTO Nav
2003 Rover 25 1.6i XL 5 DR

Tinkley
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Re: BX 19GT PROBLEMS

Post by Tinkley » Mon Feb 15, 2016 10:19 pm

If it is the coil, you will notice instantly the change in exhaust note. Helps the fuel consumption a lot too... :wink: