Hi, When the car is idling, and i press down throttle it goes down in rpm and then up, its like it is having to much gas. Can this be a mixture problem? Its a rebuild Nikki carb.

/Torben

 

More likely a problem with the accel pump or it's linkage, which is letting the engine starve slightly on throttle-up. That, or a plugged transition circuit.

 

Did you rebuild it yourself, or have someone else do it?

Things that will cause this (not all-inclusive by any means):

Missing ball or weight in the Accellerator Pump circuit
Fuel jets reversed (with large in primary and small in secondary)
Vacuum advance not hooked up, or hooked up incorrectly
Idle mixture not set


Good luck!


.

 

Yes i did rebuild it myself.
I will check the things on your list kentetsu, thanks.

Thanks for fast input.

/Torben

 

Update.
I have checked everything on the list.
Nothing was missing, but the jets was not looking good, so i changed them with the ones from my donor car. I check the, what do you call it, the flodd or the ones i plastic, 16mm and 51mm is ok. So i put i back together again, and it starts fine and the problem with the gas i gone, but now it floods istead..... anyone have some ideaes? Please

 

Check your fuel filter! I had this problem with under-delivery, and when I took the filter out to check it it was full of gunk... Then, when that cleared up, my pressure was too high, so, flooding occoured. If you have an aftermarket pump, look into a regulator.

 

Did you get the jets in the right locations? The smaller number goes in the small (primary) barrels. Get them backwards, and the car gets very unhappy...