Setting carb up after rebuild
Turbo Mini Forums

How shall I set the carb up?

It starts with the choke fully out but runs really rough, hunting alot, then dies(any throttle makes it cut out) or starts up revs to about 2800rpm and dies straight away.

The car is a standard metro turbo shall I blocked off the anti-run on valve or just leave it?

thanks

Edit: Also the car has no exhaust past the downpipe, will this have any affect or will the turbo being creating the back pressure needed?

Edited by mayoturbo on 4th Apr, 2008.

1st of all i would check that you have all the pipes on the right way round and correctly and that there are no air leaks or fuel leaks and that the dashpot oil is topped up. then set up.

pipe order shown here:
http://www.turbo-mini.com/59247/index.html

The exhaust wont be helping but it should still run. To roughly set the mixture start it up let it warm up as much as you can then wind the screw in as far as you can before it dies, then wind it out untill the revs are at there highest. Then take it for a long run and set it to about 3.5-4.5% co on an emissions tester, they run well at about that, though the legal limit is 3.5%

When i rebuilt my carb i had a similar problem to what your describing, when i wound the mixture screw all the way in, it was still running lean. i took the carb apart again and found that i had been supplied the wrong main jet sleeve (bit with plastic bit on) it was about 1mm longer than the old one. Put the old one back in and it was fine.

These pics may be of use:









cheers

just thought also make sure your advance and retard pipe is connected to the carb and dizzy or this could cause this problem!

i use this to set the float level accurately.
( a computer slot cover, a blade from my feeler gauge set and a small vice grip)

use a extra 1mm blade to set the depth , then clamp the loose blade with the vice grip

there are two (probably more it being an SU) kinds of jets :0.090 an 0.100. the larger one should be fitted and has a white plastic plastic thingie that can be a tad yellowish brown if old.

basic setting would be flush with the bridge, then two full turns down. i have been having all kind of trouble with a NA engine and i think that can be traced by running the jet too far down in the bridge.

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Edited by Sir Yun on 6th Apr, 2008.

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

Have you checked the jet? It might be sticking. I rebuilt mine recently and got symptons like yours. Simply whip the jet out and give a small wipe with 1500 paper. Dip in some lube and refit.

It's all fun and games until someone gets hurt... Then it's hilarious!

PS - the exhaust will make a little extra back pressure but mines running with nothing beyond the downpipe at the moment with no issues.

It's all fun and games until someone gets hurt... Then it's hilarious!

Thanks for the replies!

When I take the carb apart again will I need to replace the seals(again) or will it be ok

gently gently and it will be ok.

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

the seals will be fine, remember to put abit of loctite or some silicone on the dashpot screw at the front of the carb as it screws into the carb body and you can get boost leak there

Finally going to try sort this out... Had a knee op so cant do much apart from strip back a carb and have a look on forums...

I'll let you know how it goes

The new main jet sleeve is longer than the old one, but the old one looks to crap to re-use.

What do I need to adjust to fit the slightly longer jet sleeve? thanks

personally if it were me id buy a new seal kit and replace them whilst carbs off/in bits.

no longer a series, but still 1.3 turbo.

Aye, do as carl says, only took me about 2 hours fiddling with springs.
Just cross your fingers before you use it that it seals.

Back once again like a renegade master

Just got it running again thanks for the help everyone. Got another jet kit from burlen which came with the seal so thats been replaced too!