Q: New SBC first start

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Newly built SBC first time starting. Comp cam, headers, intake/carb etc etc. Started up instantly fast an easy and I brought RPMs up to 2300ish for 20 minutes for break in like Comp papers said. All was well but 15 minutes in I noticed some smoke and it was getting hotter than normal. The smoke was just a minor oil leak on valve cover dripping on header. The heat was cause I was in a garage and needed more air flow. I got a big box fan on high in front of radiator now. When I went to restart it, it wont. Just cranks and spits a bit. Waited until it cooled a little and still just cranks and cranks with a pop or two. I know it has gas and spark. Timing shouldnt of moved and it was just running fine. I dont get it.

Pull one of the spark plugs to see if they are fuel fouled. The carburetor may have flooded the engine. If plugs are wet then try to hold the carburetor wide open to try and get it to crank over. You may be getting spark and too much fuel. Once it starts then it runs at normal speeds for the cam break in again. Have a certified technician from YourMechanic diagnose your vehicle’s hard starting issue in order to have the correct repairs done.

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