There's a noise....

[Mike_exploder]

Okay, sorry if theres a ticking noise subforum, lol new here and dont mean to mess anythig up... okay for starters I just recently became an owner of a 97 ford explorer... It is sitting at 139,999 miles, and got it monday at 139,975... The engine is the 4.0 v6 sohc, and it is the 4x4 automatic tranny.... Now to the problem... It starts and runs fine and strong, but there is a clicking/bolt tapping, noise coming from the rear of the engine... you cant hear it when you rev it, but it does speed up it seems with the increased rpm... It also sounds the worst on startup... I have a few diff oppinions and ideas on what it could be... but not really sure... i could post a sound link tomorrow if that'll help... Im just looking for ideas as to what it could possibly be... ask questions if ive been to vague lol...

 

[Snowboi]

You sure its from the back of the engine? Those engines do have the timing chain issue, which sounds like your problem, but your saying its coming from the rear of the motor.

Maybe get a foot of heater hose (or a automotive stethoscope), and go around the obvious parts of the engine, and try to figure out where the noise is coming from.

Good luck.

 

[RobWilJas]

Sounds like the rear timing chain tensioner. I only know what I've read here since I don't have that motor, but it seems to be a very common problem on the 4.0 SOHC.

 

[RobWilJas]

You sure its from the back of the engine? Those engines do have the timing chain issue, which sounds like your problem, but your saying its coming from the rear of the motor.

Maybe get a foot of heater hose (or a automotive stethoscope), and go around the obvious parts of the engine, and try to figure out where the noise is coming from.

Good luck.

Those engines have three timing chains, one of which is on the rear of the engine.

 

[ragajungle]

I had a 4.0L OHV in my 99 and it had a "dry start" issue. A severe "clattering" sound that lasted no more than 2-3 seconds at start up. As the crank journals wore out with more driving the clatter at start up stayed. Eventually the bearings in the motor could no longer sustain oil pressure engine began knocking and ultimately quit.

A "bolt" tapping sound could be something as minor as a collapsed valve stem or a sever as a connecting rod wrist pin getting ready to let go. If it is the SOHC motor more than likely the rear timing chain guide is clattering. (Also bad).