I got my 83 brat runnin again, had a bad axle, but it now makes a really bad knocking noise on the driver's side when accelerating. Also it seems that the carb or soemthing may have gotten water in it, it seems like it doesn't get fuel and does this whooop whoop thing. The same thing happened to my other Brat and I sprayed carb cleaner in it and it fixed that one, tried it with this one, and it still does the same thing. I let this one sit for a while before I drove it though so maybe that has something to do with it? Any ideas? Could the engine have hydro-locked? Problems started after driving through lots of water.

Fuel filters?

Fuel filters?

 

replaced the one under the hood, along with the air filter, have one ready to go in before the pump.

Did you change the oil? Hows the oil pressure. Brat has been sitting for some time without running right? Thats really no good for an engine. Change the fluids, hope it's not a rod knock.