Hey guys can anyone tell me if the 4.0l sohc engine is an interference or non interference engine. well driving my truck today i think the timing jump a tooth. the motor still runs but very ruff and no pickup will not idle. what i'm wondering is it still worth doing the timing chain and guides or drop a engine from wrecked truck.

any help would be great
steve

 

It is an interference engine, but if you only skipped a tooth the pistons and valves should be OK.. Do not continue to run it in that condition..

A p&p engine is an unknown, not my first choice....

I would pull the engine and do a tear down.... Philip

 

If you are running a 4.6 engine I highly recomend doing the timming but only do it yourself if you are comfortable with the process cause you can destroy the engine if it is miss timmed. I just went through this exact issue on my expedition and the process will be virtually the same as longe as yours is the 4.6. As for the six banger I didnt research that but it still will have the same principals. Check out my forum that covers this. Alot of people gave me ideas, and links on how to accomplish this...Not to mention I was quoted at 1700$+ and got it all done after returning rental tools for around 320$ and it purrs like a kitten.

https://www.ford-trucks.com/forums/1...xpedition.html

This link comes with pics of my damaged timing set, and special tools I made. Hope this helps.

 

One more thing, I dont recomend one of those dirt cheap ebay timing set knock offs! They are poorly rated and I have heard stories about the chains breaking which again will mean its more then likley you will be buying a new engine or a complete rebuild with alot of new parts from smashing the valves with the pistons. I used Cloyes, as I understand they are top notch, or get it piece by piece from fordparts.com for official oem.

Just noticed yours is 4.0... I still would not replace the engine and the principals are the same to time engines. Haynes shows how to do this also.

 

If it still runs, that's unusual in the event of a timing chain issue. The repair of the passenger side chain (which runs at the back of the engine) requires engine removal.

Be prepared, this is not a fun engine to fool with.

If you do decide on a junkyard motor, go through it first and make sure it has the new chain tensioners and guides.