dochtwincam

okay im having a slight problem with my honda civic shes the 16 vavle duel carb and she started with running on 3 cylinders and now has gone to firing oil and petrol out of the exhaust and putting out a thick cloud of white smoke , she sounds worse than before and the carb where removed and cleaned down and ever since she is over revving herself and the trys to cut off and goes back upto high revs, please help thanks

Jimi Hondrix

Why is it only running on three cylinders? Dry and wet compression test performed? If one of the cylinders is low on compression and is still being inected with fuel it's not combusting the fuel in that cylinder is probably causing a rich fuel condition. A rich running condition can cause black exhaust fumes and other symptoms:
https://www.bellperformance.com/blog...running-engine
http://automedicsafrica.com/car-runn...t-fuel-supply/
http://injectorswhse.com/fuelmixture.php

Pull spark plugs and check for fouling? Do a power balance (drop) test. COmpression test if not performed already.

TomCat39

Dual Carbs, removed and what?

You have to balance dual carb motors and it's a process to do that. I'm assuming the carbs were rebuilt which definitely means they need tuning.

And since it wasn't tuned, I wouldn't be surprised if you ended up cylinder washing a cylinder by waaay too much fuel and burnt a set of rings.