Hello, My engine overheated due to lack of oil causing engine knock. Tore apart the engine and noticed that cylinder walls and piston #4 were scored. My mechanic recommended boring the cylinder to smooth out the scoring and put in an oversized (.25) honda oem piston. The pistons for the other 3 cylinders are fine, however my mechanic recommended replacing all 4 pistons though. Would this be necessary? Would it be ok to have one oversized piston or would this cause an imbalance in the engine?

 

yes it will cause an imbalance your car revs up to 8500 rpms to 9000rpms i would say replace them all rather then find out later you have to have engine ripped apart and spend twice as much no way around it spend the extra money so you know you wont have to worry in the future

 

You can do this if you balance all 4 pistons so they are the same weight. Try to get them within 1/2 gram of each, or closer if you have some really accurate scales.

 

The oversized piston would also have a larger displacement, wouldn't it?
In theory at least.

Would'n that cause imbalance?
Just curious.


hippos2k: did your MY'00 engine have the updated oil jet bolts?
If not, now is a good time to do that.

 

thanks for the input everyone, sounds like it would cause an imbalance and all 4 pistons should be replaced.

why do the oil jets need to be replaced?

 

A set of 4 pistons is going to cost you 1K. Then add the machine work costs and the cost to build the shortblock. The cost of a new shortblock is around 2500. So balance the cost and value. I think it may be cheaper in the long run to install a shortblock then to fix the motor you have.

 

x2!!!!! plus you can sell your damaged shortblock and recoup some of the costs. some people on s2ki are just looking for a block to have sleeved and built.

thats what i would do if i was you.

 

Been there, done that!

That is why I brought it up.

 

where would i find a new short block for $2500, i thought a new one would cost much more?

 

what is involved in sleeving and the purpose for doing that?