what's the "knocking" sound in my 72 VW Bus?

[busbugghia]

You may remember me, I had a 74 Porsche motor put my 72 VW Bus. Now, this motor was a 2.0 that was built up to a 2.8. While driving to work, on Jan. 1st '09 I ran outa gas, on the off ramp. Luckily I had a gas can with a couple of gallons in it, so I ran around, got the can, poured most of it into my tank... like a chinese fire drill, I ran back up and jumped in the drivers seat (traffic light was still red), tried to start my engine, but the gas wasn't there yet, ya know? and my battery was losing power, so I turned the key to on, which starts my electric fuel pump, and let my bus coast backward down the off ramp and attempted to kick start the motor. No go either, but now gas is getting to the carb. so I pump it, pray a little, turn the key and she starts up, but she sounds really rough and loud, I got less than a quarter mile to go, most of it down hill, so I go for it, my ole bus is backfiring and then starts to make a terrible knocking sound... have I killed her? Is it a bent valve? broken piston? Is it fixable? and at what cost for parts, do ya think? any help would be greatly appreciated. thanks again.

 

[Hellraizer]

It is most likely the gas that you put in it. I have a friend had the same problem. He owns a '91 nissan 300zx and he filled up his gas a started having the same problem.

He asked me what the problem was, because it started happening right after he filled it up. we thought that there was water in the gas and so added a little bit of antifreeze to the gas tank to evaporate the water, and it fixed the problem.

Ofcourse, if the noise is really loud it could be caused by some problem relating to the engine! The car is really old you know!!! the best thing is to take it to a mechanic, or someone who has worked on cars extensively!!!