Carb running rich!!

[CableSrv]

Hi guys, new to this board been a long time reader tho. I've got a problem but no money and need help diagnosing this.

I bought a color tune and decided to check my carbs rich/lean ratio..

after fully closing the mixture valve the front carb still burned yellow(rich) so this leads me to believe something isn't right. I can't adjust the mixture needle anymore The rear carb burns blue(perfect ratio per colortune diagram)

I have round top SU's on a l28e engine and n42 head in a 240z. I can only assume the person that put this together setup the carbs for the extra cc's of the l28. I've attempted to tear the carbs apart and clean them with b12 cemtool carb cleaner. I saw no wear in the needles... didn't see much on the nozzle and didn't check the float really to much.

When I put the synco tester on the front carb the engine doesn't raise or lower in rpms AT ALL, but when I put it on the rear carb the rpms drop and engine starts to stumble. Both carbs measure the right airflow so they are synced just front is pig rich and fowling my plugs!!!

If I had the cash I would order the ztheropy video and probably new needles and nozzles but alas i'm broke

Can anyone help me diagnose this issue ?

[Bruce Palmer]

The next thing I'd do is try lowering the float in the rich carb. Bend the tang on the float lever "up" to lower the float level. Be careful removing the float bowl lid to not damage the gasket. Just a little adjustment at a time until you find the right level. Get the fuel level about a 1/16" below the top of the nozzle tube.

You'll need to re-set the mixture on the fuel nozzle when you're done.

The JUST SUs video for $15 is one of the best bang for the buck resources you'll ever find for your toys.

[CableSrv]

Yea I did some search on google for tuning su's and read alot about the floats, so this sunday i'll be doing that plus my float bowls had no gasket on them... so I put them back with no gasket.. I'm assuming this was bad then... so i'll be gettings new gaskets soon then.

appreciate the info, and yea I agree if I had the money for the video i'd buy it but i'll be putting a 280zxt engine in soon anyway so no point in buying it right now