[Benno]

Im after a bit of advice on my 96 SWB zook. In the mornings on start up im getting thick black smoke, and the vibe that its only running on 3 cylinders roughly. Also poor fuel economy and fumes on back off of throttle while driving that just..um...get me a little high in transit. lol. I have a bit of an idea that the the choke may be sticking or mixture is incorrect. Any advice on fixing up carb greatly appreciated...cough...

[royce]

1st up is it a soft top? if so the exhaust needs to exit at east 5cm behind the bumper or out the side of the bumper like factory or it will fill with fumes

the smoke sounds like you have a lot more choke than you need, this can be adjusted by a little 8mm nut and screw on the wax pelet on the carb, if you look where the 2 water hoses go into the carby its on the other end of that chamber, unscrewing it will reduce the tension on the chke therby making it turn off earlier as well.

while we are there, does it have a working thermostat? too cold and it wont turn the choke off, none at all wont let the coolant up there to turn off the choke

I would go for an oil change, a good squirt of carb cleaner and new plugs and air filter too, the filter could be clogged and the the others will be buggered from running rich as well

fumes on back off giving you a headache I know only too well, your valve guides are stufed and I would look very hard for a leaky exhaust and unplugged holes in your firewall

[Sneakyzook]

Hey Benno

Take your car to a carb place and get it Overhauled.

SZ

[royce]

Sneakyzook wrote:

Hey Benno

Take your car to a carb place and get it Overhauled.

SZ

awwwww cmon sneakes, wheres yur sense of adventure

[Sneakyzook]

royce wrote:

Sneakyzook wrote:

Hey Benno

Take your car to a carb place and get it Overhauled.

SZ

awwwww cmon sneakes, wheres yur sense of adventure

Yes I think youre right I should have a go at doing some of the carb stuff one day, i think its a bit scary

[royce]

just dont turn it upside down with the top plate off

spose I should link up them manuals ey, make life easy

[Benno]

It is a soft top sierra. I bought the car a couple of years ago. It came with a straight exhaust, but have changed it so it has an elbow that shoots exhaust out to the l/h side similar to original. Recent new soft top. It also helped replacing tailgate rubber fume wise. The thermostat appears to be ok i guess cause it reaches and maintains half on Temperature gauge. Have also tried carb cleaner but to no avail after full service (air cleaner, oil change, plugs,etc). I have made sure all firewall plugs are well sealed. I should have a look at the choke adjustment on the wax pellety thingie you were talking bout, sounds like a good start. What sort of life are expected from the cylinder heads? It has around 180,000km, which i spose would be getting on for a smallish hard working 1.3 engine.

[royce]

yeah your getting to that sorta stage

when its up to temp feel the coolant lines *careful hot* and make sure they are the same temp, the carb can get blocked up and the coolant doesnt get through so choke doesnt turn off

[Benno]

I have felt the coolant lines and they seem to be the same temperature running through the choke.

[royce]

ok so now you know the lines arent blocked (common), next would be to take the intake of the carb (10mm nut in the middle) and see if the choke flap is fully closed when cold and if it fully opens when hot

chances are if its adjusted too tight when cold it wont open up fully when hot

[The_Pope]

th

[Benno]

hey royce, got the car up to temp today while observing choke butterfly. It opened almost completely veritical, wasnt far off. It did seem to have a bit of play though both ways, not sure if this is normal or not. Return spring is not broken. grrr.....anyone know how easy it is to fit a weber 32/36......

[royce]

o next one (yes chokes do suck to check out) see from cold a, how long it takes for the choke to open and b, how far the needle has moved.

or you can adjsut it fully open when cold and see how it goes for smoke, then work your way back again

[Benno]

Wooohooo, worked out the black smoke probs. The problem was within the vacuum linkage to the choke. The shaft had a bit of freeplay, and turned inside the diaphragm too freely, therefore it didnt allow the tang on the shaft to come into contact with the choke tang, allowing it to choke up to excess while running. To ensure proper location of the shaft, i decided to araldite it in a fixed position to line up with the choke on the diagphragm end so it wouldnt turn. Thanks Royce for your help, i tried this just before de adjusting the choke and working from there. Cheers!

[royce]

good to hear you got it going

see carbys arent that bad if you take the time to understand how they work