Help! Engine Died

Ill post pics when I get home. Thanks for you help and thoughts...I think I'll hold off on the 360.

 

Here's the broken rod. If you look at the crankshaft you can see a small hole...can this be fixed or do I need a new crankshaft?

 

The crankshaft has an oil gallery in the middle of it. The hole in the journal delivers oil to the bearing.

How much do you know about engines? I suggest you do some reading to get up to speed on the issues involved in rebuilding. The factory manual is a good place to start. This book http://www.amazon.com/Engine-Builders-Handbook-Tom-Monroe/dp/1557882452/ref=ntt_at_ep_dpi_2 has a lot of good information and is inexpensive.

Typically if the bottom end of the connecting rod breaks, it will flop around and damage the crankshaft. It may be cheaper to find a good used core, and rebuild that, rather than to rebuild this block. The procedure will be the same, but it may be more economical to start with a different core.

I'd also suggest you start shopping around for a machine shop now. You can do the assembly yourself, but not the machining operations.

 

Thanks for the book suggestion...I'm not talking about the hole for the oil. Like you said, when the bottom of the rod broke it broke a separate hole in the crankshaft (its the black part on the shaft in the pic. I'm picking up a 304 this weekend that I'm gonna rebuild. I just didn't know if the crank can be fixed or should be scraped.

 

Well, wrt the crank, it's a cast crank, and they are seldom reused without machining. A forged steel crank sometimes survives a bearing failure, but not cast. Most engines have a cast crank today, because forging is more expensive.

Typically you would have turned in your crank for a "crank kit" which includes a crank turned undersize and the proper bearings. However, if there is a gouge in the crank, it's unlikely the shop will accept it as a core. You can still get the crank kit, but you'd have to pay a core charge. These cranks are common, since the 304 and 360 use the same crank, and there were lots of 360s made. It could be welded, but it's unlikely the rebuilder would bother to fix it - so, they'll scrap it.

With your replacement 304, you may be fit new bearings without grinding the crank. If you take it to a shop, they'll probably suggest you exchange it for a crank kit. If they tell you you can use the crank, then they are at least a little bit liable if there is something wrong with it ... but you can measure the new crank yourself, and see if it needs turning.