[suzibob]

Hi fellow auszookers..

Over the last nearly 3 months I've had issues with my carby on the Sierra. I know the carby just about inside out but obviously not enough to fix my problems.

So again I ask for assistance. My current issue is rough idle or no idle when cold. It starts, runs for 5 secs then "chokes" and stalls. You have to wait for the thing to warm up, then it is driveable. On hot idle, it will idle but very low and rough (sometimes 100-200rpm). It's not a clean idle. So you adjust mixture and idling to suit. It will then run fine until it gets cold again and then you have to repeat the whole procedure.
I had this "professionally" tuned the other day and the guy told me that it kept adjusting it's miture ratio by itself (between 0.7 - 2.5 I think he said). So he tried selling a webber to me which I don't want. I've rebuilt the carby so many times now it's not funny. Replaced and been around all vac lines and gaskets with carby cleaner to find a leak but nothing.. I've checked the choke , blocked off the egr, checked wiring and earth points, replaced leads, plugs, rotor, dizzy cap - and possibly other stuff I'm forgetting about right now.

Just out of ideas now...

Also, if this helps, I swapped my main and sec jets over on last rebuild and it ran fine, just no real power up top. I didn't want to keep it this way just incase it was to rich. - although I did lean it out.

If anyone has any other ideas, please tell. Thanks.

[suzukilwb]

adjust the accelerator cable so it pulls the thingy back till it idles when worm or idles to high when it worms up done it onetime before i rebuilt my carby would a different carby fix it? and ur auto chock might be fucked so rev it till it will idle ok then drive it all i do with mine then when it worms up a bit then its fine few ideas not good one but might help

[Brenton87]

I would take your fuel tank off and clean it out. There may be shit in the bottom that keeps getting stirred up and getting into the carby. Also try increasing the idle speed and run it for a bit like that to try clean the jets out. And failing that take the mixture screw out and blow compressed air through it. If you have a vitara motor take the sensor out and blow through that with compressed air. And if it is a sierra carby, there should be a couple of bolts for the bowl you can undo and blow through that too. I have had the same problem many times and it has pretty much always worked. Also, if there is a poosbility of water in the fuel, put a bottle of metho in the tank.

[suzibob]

Hey guys, yeah I have had the tank off, infact I've been through the whole fuel system. Changed fuel filters, installed another inline filter right before carby. Yes it's the sierra motor (G13BA - 94 model). The choke seems to work as it should. It was running sweet before I swapped the jets back to normal, and then it started playing up again. Surely the jets aren't the issue. - no damage or blockages.

The fault seems to be as if it's sucking unmetered air from somewhere, but I can't seem to find it. I've stripped the carb back to basics but it still plays up when cold. Another thing to note is it won't rev by the choke idle up adjustment as it runs really rough. It will free rev ok by the accelerator but as soon as you put load on it (ie: takeoff), it stalls. It is gutless as all hell if you don't sit there and rev it for at least 5 mins to warm it up...

Really thinking of swapping the jets back to opposite... Just concerned about engine damage...

[joeblow]

i'm trying to resist.....









i really am.......

[atari4x4]

V

[joeblow]

i

[suzibob]

Vitara carb??

[joeblow]

[atari4x4]

[suzibob]

Yeah not exactly the answer I was lookin for but if there is an advantage of doin it (except for the obvious) then I guess that's what I got to do. What model vitara will bolt on?? Same year? What's the difference between the original and vitara carbs??

[Fmoss3]

sell the car, buy a different one

at the rate your going it sounds like less trouble

[royce]

have you adjusted the choke properly? are your throttle spindles worn?
if you have 'rebuilt' it 4 times already obviously you are doing something wrong

might I suggest teh carby bloke at Kippa Ring Redcliffe, apparently does good stuff with them, I have never tried him cause I simply cleaned mine up when I bought my sierra and set it up per the manual and had more troubles for 4 years after

[suzibob]

4 times... More like 44 times. Its at that stage that I wil have to get another kit to put through it from wear and tear just from disassembling it all the time. What I don't get, is it was fine before I swapped the jets back to normal. Might swap them back to bigger (105) in primary, smaller (98 I think) in secondary and retune. Surely the brass jet ain't the cause... Doesn't add up. I have the 72mb old service manual PDF file that I've been sticking to aswell..

In the back of my head I knew that when I swapped the jets back to normal, it was going to start to play up... Should of left it. - least I could takeoff in 2nd gear...

[Brenton87]

hmmm... it sounds like no end of trouble. Barry Mac, who is 'Mac Tuned' at Morayfield is the best guy to see. He has helped me with all my carb and other mecahnical problems. Good luck with it mate. Let us know how you go.