I decided to put a HS50 on my Rupp R2 while I get the 10 HP vibration issues worked out. I partially freshened up a low use 50 I have cleaned and lapped the valves, put in new points, condenser, coil and carburetor, when I tried to start the 50 it was difficult to get going and when I dialed in the carb I noticed it didn't want to rev like my Tec engines do then it stalled at idle and would not start again. I found fuel puddling in the intake and below the valve but the spark plug was dry, the 50 didn't want to fire on Ether. After a couple of hours I had enough and changed that 50 out for another 50 I was running last year and when the second engine was all setup it did the same thing would not run had gas puddling in the intake and a dry spark plug, after some evaluation the only part that was different than last years 50 or any other 50 I have run was the drop slant intake with a level carb, I had been running a regular HS50 straight intake with the carb at a 20 degree angle before with no issues so I changed the intake back to 20 degree angle it fired right up and runs fine, the carb has the float set properly for a level carb. The only thing I could find that was off is the intake floor where it mounts to the block is .1" lower than the block creating a step up maybe that step creates excess air deflection enough to mess up the intake flow? Tomorrow I will add some epoxy to the intake floor on that end and blend the manifold to the block the way it should be then try it again, anyone else experience this issue? Below is the intake gasket shown how it goes on the HS50 block with the drop slant intake I marked where the step impression is.
Tony

Tony

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