14 replies to this topic

[Fiadmin]

Hello Miniacs,

 

I try to tune my carburetor on a car fitted with standard stage 1 kit from minispares - on the Haynes manual it's written to start settings with the jet bearing flush with the bridge - engine doesn't start there, so going deep and deep the engine seems to run ok (can't do a road test so far as no insurance and MOT)

 

but now I'm around 3 or 4mm under the bridge and from the smell of the exhaust It's quite rich mixture... not sure I can get a MOT with this...

 

what about your settings ? do you go so far unscrewing the jet ?

Edited by Fiadmin, 06 June 2022 - 03:53 PM.

[cal844]

3mm maximum down from the bridge

[sonscar]

I always thought it was 1.73 mm or thereabouts.Long while since I read Haynes but does it not say two turns down from the bridge to start?Steve..

[cal844]

I always thought it was 1.73 mm or thereabouts.Long while since I read Haynes but does it not say two turns down from the bridge to start?Steve..

Two turns as a starting point, then go from there, ideally you want the jet to be less than 3mm down from the bridge

[timmy850]

Are you using the choke to start the engine from cold? Are you having issues with it starting once warmed up?

[Fiadmin]

Hello timmy850, with actual setting (3-4mm under bridge) I can start engine without starter but it seems the engine is running rough but I didn't let it warm up to see if it runs better so far.

 

At this point I have another question for all users :

 

Do you start your engines fiited with carburetors without starter when the weather is warm, or do you use starter whatever it's winter or summer ?

Edited by Fiadmin, 07 June 2022 - 10:30 AM.

[cal844]

My minis always need choke to run when cold

[sonscar]

Do not adjust the carb until the engine is at full operating temperature.Use choke to start it and until it will run by itself without it,Steve..

[timmy850]

Yes you need to use the choke

If you make it rich enough by adjusting the jet down to start then it’ll be much too rich when it warms up

[LD_Framework]

Hi guys, I'll make this topic alive again because what I need is related to the carb setting and don't want to start a new topic.
Ho do you use to set the right mixture? I was looking online for a Gunson Colortune, is there any other option to this one?

How do you set all up? tightening and loosing the jet screw and then check the spark colour or use a different system? Use just your experience?  The gunson looks more easy and fast method but is it accurate?

Also, is there any trick to set the idle? I have a cooper rover 91 with the filter box original, and the idle screw is under the box, so every time I need to disassembly all the filter box, tight or loose the screw and then do it again and again. 
Any suggestion much appreciated!

[68+86auto]

Hi guys, I'll make this topic alive again because what I need is related to the carb setting and don't want to start a new topic.
Ho do you use to set the right mixture? I was looking online for a Gunson Colortune, is there any other option to this one?

How do you set all up? tightening and loosing the jet screw and then check the spark colour or use a different system? Use just your experience?  The gunson looks more easy and fast method but is it accurate?

Also, is there any trick to set the idle? I have a cooper rover 91 with the filter box original, and the idle screw is under the box, so every time I need to disassembly all the filter box, tight or loose the screw and then do it again and again. 
Any suggestion much appreciated!

 

The gunson gastester would be better.

[coopertaz]

have used colourtune and then road tesing with success but depends on your start point. if you have chucked loads of things on may not get anywhere near without needle change or modification aswell. Are you just doing a tune up or fitting stage one kit and recommended needle? for idle speed fitting standard airbox and filter shouldn't cause enough restriction to reduce engine idle speed

[LD_Framework]

have used colourtune and then road tesing with success but depends on your start point. if you have chucked loads of things on may not get anywhere near without needle change or modification aswell. Are you just doing a tune up or fitting stage one kit and recommended needle? for idle speed fitting standard airbox and filter shouldn't cause enough restriction to reduce engine idle speed

fitting stage one kit with recommended needle, just want to be sure to use the best options.

what you mean about the idle restriction? the screw is under the box so... need to disassemble every time. 

[timmy850]

have used colourtune and then road tesing with success but depends on your start point. if you have chucked loads of things on may not get anywhere near without needle change or modification aswell. Are you just doing a tune up or fitting stage one kit and recommended needle? for idle speed fitting standard airbox and filter shouldn't cause enough restriction to reduce engine idle speed

fitting stage one kit with recommended needle, just want to be sure to use the best options.
what you mean about the idle restriction? the screw is under the box so... need to disassemble every time.

What carb have you got? What air filter?

[coopertaz]

 

have used colourtune and then road tesing with success but depends on your start point. if you have chucked loads of things on may not get anywhere near without needle change or modification aswell. Are you just doing a tune up or fitting stage one kit and recommended needle? for idle speed fitting standard airbox and filter shouldn't cause enough restriction to reduce engine idle speed

fitting stage one kit with recommended needle, just want to be sure to use the best options.

what you mean about the idle restriction? the screw is under the box so... need to disassemble every time. 

 

the kit will usually come with free flow air filter and even if this is in the atsndard airbox fitting this after setting up the carb shouldn't drop the idle speed by enough to require removing air filter to adjust again. Just make sure engine is up to normal temp. before adjusting carb. would also suggest holes at front of standard airbox if using that