2.5L ('98-'01) Engine locks up

[pard]

2000 Ranger 2.5 manual transmission, 252,000 miles.
Driving at 35 MPH crossing RR and engine locked up. has new starter, fly wheel a little buggered. Push started it and came unlocked. ran for a couple of days, put in garage and next day tried to start but was locked up. took all plugs out and spins great. put plugs back in and locked. What do i need to do?

 

[RonD]

Welcome to TRS

Assuming no mechanical noises your timing belt may have slipped
2.5l used a timing belt that needs to be changed every 100k miles

Starter motor may not have enough torque to spin engine with incorrect valve timing, so push start can work but not starter motor
OR
It could be battery or battery cables can not supply enough amps to turn over engine
Test battery volts, 12.3-12.8volts is expected

 

[Dirtman]

Seized motor won't care if plugs are in or not. Definitely sounds like a weak battery, weak starter, or timing issue like Ron said.

Plus it takes an act of god to seize a Lima engine. The guys at the race track run them in demolition derby cars without coolant, just fill the block with concrete and they still run forever.

 

[scotts90ranger]

Yeah, from my experience to lock one up takes doing something stupid like not tightening the rod nuts properly or whatever happened on my old 2.3L turbo (RIP, it ran better than my current one, but I just threw the current one together...), all I know is one of the rod nuts fell off then the block and oil pan windowed and made a heck of a noise...