Bottom end rebuild, basic questions

[thereisnoyun]

if I were to rebuild a bottom end with new rod bearing, main bearing and rings.

1.) do I need to rehone the cylinders? if they look good do I just get them to clean it and keep it the way it is?

2.) does the crank need to be polished?

3.) should I balance the rod?

4.) freeze plugs?

ofcourse I want to spend as little as possible, but at hte same time I want it to be complete, but not overkill.

anyone with experience want to enlighten me on what to replace?

[jlevie]

If you are going to replace the rings, the cylinders should be honed.

Polishing the crank is recommend, but not always essential.

The rods will probably need to have new wrist pin bearings fitted, but don't need to be balanced.

Whether the freeze plugs need to be replaced depends on their condition, which in turn depends on how well the engine was maintained in the past. If coolant was always and changed every other year the freeze plugs should be fine. Otherwise they might be rather badly corroded, which would mean they should be replaced.

You should also replace the oil pump and make sure that all oil galleries are completely clean.

[e30this]

Hmm This should answer most of your questions on the right way to rebuild a motor.

http://www.e30tech.com/forum/showthread.php?t=59017

And if you dont do it right you could end up like this.

http://www.e30tech.com/forum/showthread.php?t=77470

And spending double if not triple what you did the first time.

[thereisnoyun]

thanks guys, any more info welcomed. this is exactly what I needed.