I've got 2003 F-150 Supercrew with 4.6 windsor. Has been great truck has 230,000 miles. Was driving down the road and it quit running. Took home removed timing chain cover and found drivers side tensioner broke into pieces. I've got plugs out and of course fan belt off. Motor won't turn over. Was good on oil never heard any knocking. Can anyone tell me why my motor is now locked up. Is it an interference engine. How do I fix it. Any help greatly appreciated.

 

U may simply have broken parts lodged. Carefully continue to look for them. Fords 4 cylinder and Timing belt motors were considered interference engines. The Timing chain engines are close but not a Cigar usually. It would be more like a valve broke or keeper popped off, broke valve spring sort of problem probly.

 

i assume you towed it home, if the motor is locked up? You are saying you can't turn over your engine??? That can't be good. When it shut off the first time what did it do when you tried to crank it over again? Was it just dead, no turning over?

If your guides are broken, it's possible they are in pieces in your oil pan (mine were) and have clogged your oil pump. Thus, you have a full pan of oil but no oil in the motor, and the motor seized (I hope that is not the case).

 

It's an interference engine according to the service manual, this is straight from the timing set procedure.

"NOTICE: Since the engine is not free-wheeling, timing procedures must be followed exactly or piston and valve damage can occur."

Odds are it's going to get expensive.

-Steve

 

It sounds like his motor was running, stopped running (failed), and now is not turning.

Was the motor free turning prior to you removing timing chains? If so then I think Steve is probably correct.

 

Don't know exactly what U R doing right now. When the adjuster broke off the slack chain would shut off the motor. The cam would not advance. Look for broke parts in the front caught locking it up, carefully before deciding on the motor. If U find a broken valve U probably have a broken piston and bent rod too. These would have made bad sound.