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Author Topic:   alcohol carb maintenance
posted January 01, 2001 07:57 PM
I'm just now switching to alcohol and would like to hear about some maintenance tips. Is there anything different you do in the off season or in between races? Do you like to run top end lube? Also how often do you change your oil if your using synthetic? Oh another thing these fragrances seem to make the alcohol a little easier to tolerate out of the exhaust, do they hurt performance or anything?

Hammer 1
posted January 01, 2001 08:48 PM
We have run both Cam 2 Alky and clear alcohol treated with Klotz additive. I suggest you run some type of lube to keep the corrosion problem to a minimum. At the end of a race evening we drain both fuel bowls on the carb and fill each with gas. Actuate both the primary and secondary linkage to clear all alcohol. I also suggest running a fuel filter with the stainless steel element. I've been told that because the alcohol absorbs moisture,the paper elements are more prone to blockage. As far as oil changes, I change mine after every 3 runs, but I run mineral base oil (old school) Hope this helps.

posted January 01, 2001 08:49 PM
A little info regarding oils. I worked for an oil additive company at one time and the following is based on testing we conducted at NASA.
Petroleum based oils do the best job as far as lubrication is concerned. Any good name brand oil will do the job. Synthetic based oils do the job when trying to control heat. Synthetics were developed due to the tremendous amount of heat produced by todays modern automotive engines. The best of both worlds is a synthetic blend.
Additives can be of tremendous benefit when used properly in a racing engine to control piston scuff and bearing damage as well as helping to keep an oil clean and useful. Engine oil actually can last longer than you'd think. The problem is dirt that contaminates the oil.
Due to the fact that racing engines consume large amounts of dust and grit, engine oil needs to be serviced often in-order to flush the engine of outside contaminents(this includes filter replacement). There are actually some new type filter systems being used on semi's that allow the engine oil to be used for 100,000 miles and more! Thus proving the fact that contaminents are the key factor regarding engine wear and failure, NOT the oil itself.
Also if engine oil becomes diluted from the use of alcohol, it needs to be replaced more often to remove this contaminent.
Once engine oil reaches a certain temperature, the alcohol in the oil should actually evaporate into the atmosphere unless there was an extreme amount present.
Alcohol contaminated engine oil will not only smell like alcohol, but will also turn a yellowish color as well. Remember, the engine oil will carry the alcohol suspended in the engine oil to bearing surfaces and cylinder walls causing damage if left in for extended periods of time. Even the best engine oil will only carry about 9 to 10% of alcohol in suspension carrying it away from vital engine parts, this allows 90% of the remaining alcohol to wreak havoc on engine bearings and other vital components.
My advise is to keep an eye on your oil to detect any type of contamination and replace it as soon as possible. If all looks good, consult your engine builder for his recommendation or as soon as the oil starts to discolor(this shows oil contamination).
The main objective here is to remove contaminents and help provide clean lubrication for a healthy engine.

I hope this has helped.

Racer 111
posted January 02, 2001 07:40 PM
Be careful with syn oils, they sometimes dont mix with alky.

posted January 02, 2001 09:02 PM
20-50 is my choice always. This gives the proper lubrication needed at both ends of the heat range. And I dont care if you gotta miss hotlaps, make sure you get the engine oil temp to a desirable level before you subject your engine to high RPM's.

posted January 03, 2001 06:41 PM
Be very carefull on your fuel filter selection. I don't know the amount of fuel
your engine requires, but filters are rated
by gallons per hour. You can have the best of
everything and the filter can cause a melt
down on the big end. If you have to run the
stock type pump, be sure you get the alcohol
version. Bo Laws helped me out after I melted
pistons twice. Alcohol is nice but EVERYTHING
must be right in order work properly.

Artie Perilloux

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