Timing Chain question

[bizzs]

I have an 03 Explorer with 97,000 miles. I am the original owner and serviced it routinely. It runs great and has no problems. Recently, when I start the engine when its cold, I hear a slight rattle on start, and a rattle sound when I accelerate the engine from a dead start when its warm. The rattle is very slight and I suspect its the timing chain adjuster. I have read there are two timing chains in the V6 and I was wondering how I can analyze which one it could be. It is not a problem right now but I know it could led into one in the near future. Any comments would be appreciated.

Thanks
bizzs

 

[Number4]

Get an automotive stethoscope, they're $9 at most stores.
Wear safety glasses, place it against the front or rear cover and have someone start the engine.
Do this on a cold start.

Every day you drive in this condition, you're a day closer to dropping $3500 on an engine install. The 4.0's are known to just let go.

 

[2000StreetRod]

Timing chain rattle resolution process - SOHC V6

I wrote the following thread for 2nd Gen Explorers but it may be useful for your 3rd Gen: Timing chain rattle resolution process - SOHC V6

Using a mechanic's stethoscope and a length of flexible tube I thought I had isolated my rattle to the left (front) cassette. Upon visual inspection I found that the right (rear) cassette was broken. Sounds internal to the engine echo off the walls making it difficult to determine the source.