Need 18R Carby Help Please! Not Idling/running Properly...

[polaegame]

G'day Starski here! I know this isn't corolla specific, but I always get the best help from this forum.

Bought my new 1981 Hilux over the summer, and has been running great, please check out the picture attached.

Anyhow... now it doesn't idle properly after running for a while, it's fine at start up but then won't accelerate properly and conks out at idle when I'm stopped at the lights.

I've tried adjusting the float level, timing, idle and idle mixture, and blocking off vacuum hoses for all the emissions rubbish, but all to no avail! My dad reckons a vaccuum leak somewhere but I can't find it...

 

Just yesterday it start running even worse, now when I apply partial throttle it craps out, I have to rev it heaps just to get it going, but it stalls itself constantly, and it back fires when it's running constantly.

Any help or suggestions appreciated, it's a Nikki carb if thats of any help

Thanks

Starski

[polaegame]

 

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[altezzaclub]

Either a vac leak or a blocked jet.

 

Strip the carby and blow out the jets and passages with compressed air, or flush them out with petrol in a syringe. Not hard to do, takes half an hour.

 

Does the carb have the window in the side with a line for float level??

[polaegame]

it does, it was very high, but i've adjusted it now it sits just above half way. I will try that, should I buy new gaskets and that? A rebuild kit is 70 bucks plus I gotta wait for it, would rather fix the problem tomorrow if possible of course.

[Banjo]

Hi Starski,

Nice looking Hilux. Feel at home here. Lots of us pinch bits off Hilux utes and upgrade our Corollas. Calipers, MC etc.

 

I reckon your Dad's on the right track. Sounds like it's running very lean. The other place you can get a vaccum leak is between the carby bottom flange & the manifold. Another culprit is the inlet flange between manifold & the head. Just check to see if all the nuts & bolts between manifold & head are tight. Sometimes if there is a leak there, you can just tighten the manifold bolts & nuts up, but if it has been leaking for a while, you are better unbolting the manifold, cleaning both surfaces & installing a new gasket.

 

Cheers Banjo

[polaegame]

Thanks for the advice everyone, I'll let yous know how I go tomorrow :)

Edited May 14, 2013 by polaegame

[altezzaclub]

should I buy new gaskets and that

 

I didn't- I have a Datsun 1600 sitting in the shed for .. um.. close to 10years now, and I fire it up a few times a year. The carb dries out and when it wouldn't run last time I pulled it apart and hosed it through with petrol to clear the tar out. Its a Nikki too.

[you_nes]

now it doesn't idle properly after running for a while

 

So its fine cold? then gets worse as it warms up? sounds a bit like the symptoms of a coil braking down, or bad points.

Might pay to check over the ignition system before you pull the carb to bits.

[polaegame]

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  So its fine cold? then gets worse as it warms up? sounds a bit like the symptoms of a coil braking down, or bad points.
  Might pay to check over the ignition system before you pull the carb to bits.
  

  
   
   
  I suspect because of the choke though, because it appears to idle and run better when I choke it with my hand.
  
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[you_nes]

well that probably rules out a vacuum problem then. Given that you have already adjusted float hight etc, I'd still check the ignition side of things, most of the time when there is a fault I can't find, its usually the damn electrons!