2000 jeep Cherokee 4.0 4WD:

my ticking noise i thought was a wrist pin ended in a cracked off piston skirt.
cylinder wall looks amazingly fine. when the break actually happened i herd a change in the noise and immediately parked the truck.

so i have the piston out.. motor is still in car with head and oil plan removed.... can i just replace the bad piston and rod and call it a day? im on a budget, and a time limit...
i rebuilt the head and put all new lifters in.... so the top is good....

 

That's a tough call to make. I had the same problem tho (see my avatar). Broke the number 6 piston skirt at the back of the motor. I pulled mine and rebuilt it. My cylinder wall was fine as well. Did'nt send the block to have it bored over. Did send the head to a machine shop tho. I actually thought about just replacing that one piston that was broken. In the end i just could'nt... But i can say that you'll have around $1000 in a rebuild considering your head is ok. You could try to replace that one piston and hope for the best and if that does'nt work you could get a whole junkyard engine cheaper than rebuilding the one you have.

 

Droping one in would seem like a temp fix to me. I would get a used motor. Around here its cheeper then a new set of pistions. Then put the old one up for sale. Allt of people going stroker like to have another block to do it on to minimize down time

 

That's a good idea. New pistons are expensive. That's where alot of my rebuild money went.

 

Ive put spare piston and rod laying around into a hydro-locked motor with only a seal kit and 1 bearing then tried to kill it out wheeling just messing around. Also left the block in the jeep and just had the head and pan off like you. It burned oil due to another connecting rod that was all bent up and valve seals where blown out from the water (found during stroker build for friend) but would never die.

 

I'd say go for it. But I would start saving for a rebuild.

 

With my chevy pickup (5.3L vortec) po dropped a screw driver bit down the intake port and forgot about it (he was replacing intake gaskets due to faulty knock sensors), he started it up and ping ping ping, he then let it sit and sold the truck to me. When I took the head off the piston had a hole through it, took the oil pan off and pieces of the piston were in the pan. I was also under the budget curse and got one piston and one new set of rings, honed out the cylinder (no wall damage), connecting rod was fine, reassembled engine after checking bearing clearances and new ring clearances, engine ran fine for another year until I sold it. I had people telling me that doing just one piston would throw the crank off balance, but I had no new noises or anything. So with my experience, just one new piston worked fine for me. Granted it wasn't the 4.0.

 

If I was on a tight budget. I hone and measure for rings. New piston and old rod and bearing. Drive gently and save for fresher motor.