1970 Cheetah jet with a 455 olds

[stdutcher]

Hello to all I'm new here, I just bought my 1st jet boat its in great shape runs great but It has a tapping in the oil pan more like a banging, the guy i got it from says its the crank hitting the oil pan has anyone heard of this? he claims the motor is rebuilt he had some receipts for parts so I'm just not sure whats going on , I only gave the guy 200 bucks for the boat so I'm not out much the trailer is worth that, any advice would be great .. thanks

[rasorinc]

Can you reach under the engine and feel the bottom of the pan? You want to find if it is dented in or pressed in at all. If your crank is hitting the pan it would wear a hole very quickly. Unless there is a dent inward then that is not the problem.

[stdutcher]

I don't feel a dent but when its running you can feel it hit the pan

[drmiller100]

2 choices. run it until it blows up, or pull the engine, pull the pan and see.

very likely it is a rod caused by cavitation when the guy jumped a wake, overreved the engine, and stretched a rod.

buy a rev limiter.

[stdutcher]

well I'm happy to report that after 2 long days and a lot of headache the motor is out and the pan was dropped you could see where it was hitting the pan so i took my fix all tool (hammer) and beat the stuffing out of the pan put it back on and took it out to the water and no more noise yahoo thanks for all your help