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ALCOHOL CARBURETORS

1. How much fuel pressure does my C&S alcohol carburetor require?

   2-3 PSI at idle with 8-1/2 to 9-1/2 PSI at wide-open throttle under load is adequate for up to 600 horsepower. And for 600 to 900 horsepower, 1-2 PSI at idle and 9-1/2 to 10-1/2 at wide-open throttle under loads, in most cases.

2. No matter what size jet I put in my carburetor the engine still runs hot. What’s wrong?

   In most cases this is due to inadequate fuel delivery to the carburetor or the alcohol you are using has too high a water content. Water content is tested with a hydrometer and should be .788 or lighter on specific gravity at 75 degrees F. Alcohol that is labeled 99.9% pure is preferred. Be cautious of buying fuel from bulk tank distributors. Fuel additive will not fix bad alcohol. Alcohol should be stored in a cool, dry place and remain sealed.

3. What is the preferred fuel delivery for alcohol?

   C&S recommends: Belt Driven Fuel Pump 4000 series, -10 line kit P8020, Fuel Filter 2150, Fuel Log 4604, Carburetor to log fitting P8010 and Return line kit P8025.

4. How can I tell if my alcohol carburetor is running lean?

   There are several indicators, one of which is damaged parts such as spark plugs (ground strap, porcelain areas) and pistons. In most cases, on small block Chevy engines, our leanest cylinders are usually 3 and 5. Another indicator is excessive engine temperature. C&S offers a carburetor modification that fixes this. It is called a 6 Jet Modification that allows the user to richen 3 and 5 cylinders separately from the rest of the engine.

5. My alcohol carburetor is milking the oil. Why is that?

   Generally caused by an over-rich condition. Sometimes in base adjustment or float settings or trying to use excessive fuel amounts to control engine temperature when a cooling system problem needs to be addressed.

6. Do I need a Crankcase Evacuation Pump Kit?

   Almost every engine could benefit from a Crankcase Evacuation System (4330AK, 4335AK, 4340AK or 4335AK, depending on your application). The benefits are improved oil control, increased horsepower, removal of water/alcohol contaminants, reduced oil wind age and may be used with wet or dry sump.

7. I am converting from gas to alcohol. What heat range plug should I use?

   Usually the same heat range or one step colder is sufficient.

8. How do I read spark plugs on alcohol?

   Due to the fact that alcohol is a clean burning fuel and leaves very little carbon residue, it is very difficult to read plugs on alcohol. C&S recommends use of a Rich/Lean Indicator 70194-1.

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