Carburetor adjustment

Various, various and more various!
Post Reply
bender_cl
Posts: 5
Joined: 14 Jun 2010 09:06 pm

Carburetor adjustment

Post by bender_cl » 15 Jun 2010 09:06 pm

how is optimal value for Carburetor adjustment in a volvo 360GL?

User avatar
bogbasic
Posts: 1861
Joined: 21 Nov 2004 10:12 pm
Location: New Malden, Surrey.
Contact:

Re: Carburetor adjustment

Post by bogbasic » 15 Jun 2010 11:17 pm

I tried to do this with a 'Colortune' but I had no luck - couldn't see the flame.... so I had to do it by listening.... when the engine sounds like its running best, stop turning the screw. Cheers, bogbasic.
1988 340 1.4 GL, 218k, 5 door (Grey Bess). Gone to CBA.
1991 340 1.7 GL, 64k, 5 door, petrol blue (Deep Blue).
1988 360 2.0 GLE, 140k, 5 door, ocean blue metallic (Blue Bess).
1989 340 1.7 GL, 108k, 3 door (Red Ness).
More info here!

Ride_on
Posts: 2262
Joined: 26 May 2009 05:34 pm
Location: Belfast, N. Ireland

Re: Carburetor adjustment

Post by Ride_on » 15 Jun 2010 11:38 pm

The proper home way is using a gas 'anaylser', like Gunson, but they are temperamental and use the thermal properties of the exhaust to compare to air. They are very sensitive to wind and need left to sit for ages to settle depending on how accurate you want it.

Real professional kit uses proper gas sensors.

Most 360s you are looking for around 1.5%. (1% to 2.5% in haynes for B200K)
1980 345 DL_______1987 360 GLE (project car restored to GLT spec and B230FT'd)
1984 360 GLT______1987 360 GLT
1983 360 GLS______1989 360 GLE
1985 340 GL_______1986 340 1.4
1985 360 GLS______1995 940 SE 2.3 Turbo Estate (daily)
1987 340 GL 1.7

User avatar
jtbo
Posts: 5805
Joined: 23 Jul 2004 03:50 am
Location: Finland, middle of nowhere
Contact:

Re: Carburetor adjustment

Post by jtbo » 16 Jun 2010 10:28 am

For older car often bit rich is better, for 240 I have heard setting it around 2.0% would work best.

Anyway few have access to analyzer, in old days even fewer had access to such, so there is method to adjust idle mixture into proper zone without any analyzer.

Hanynes book of Carburettors instruct procedure as follows:
1 Run engine 3000rpm for 30 seconds to clear the manifold of fuel vapours, then allow engine to idle.

2 Use the idle speed adjustment screw to set the correct idle speed at the upper limit of the of the tolerance given in specifications.

3 Remove tamper proof plug and adjust the idle mixture control screw until the highest engine speed is recorded.

Repeat 2&3 until highest highest steady idle speed is reached (using correct idle speed as starting point)

Clear the manifold every 30 seconds during the setting operation by running the engine at 3000rpm for 30 seconds

Screw in idle mixture control screw until the engine speed is reduced by 25rpm
Highest steady idle means that engine runs smooth and not shaking.

With those adjustments it is enough close, will pass mot if there are no other problems, like for example air leaks, which will cause idle to be set wrong, but it is same with gas analyzer, if there are air leaks, no matter how tiny they are, carb will be off, very hard to adjust and very hard to make car run properly, so checking that carb base is not warped and that there are no air leaks is a must before making adjustments.
Volvo 360GL -88 -under restoration-
Volvo 343DL vario -81 -running- Image
Volvo 240 Diesel -83 -undecided-
Citroen ZX Dturbo -97 -daily- ImageImage

Post Reply