Engine Knock / Tap

[martinctb]

I have a 1997 Explorer 4.0Lt and its developed a noise the noise it not that noisey from the engine compartment just a slight tapping noise, but inder the car its have put a steposcope on the cats they don't sound to bad the noise seems to be coming from the bell housing area (but engine noises always travel) when i rev the car up the noise seems to stay concent and loud, the car has only done 80000 miles,no smoke drives great, has anyone come across this before. If it is the rear cartridge can they be replaced with the engine in the car, waste of time asking the garages in UK as i was quoted $4000 to do the timing chains, if anyone has the route and could email how to do it that would be great otherwise a bit of advise of what to check and how. martin in UK

 

[Howard]

I'm afraid you have to take the engine out to do the rear timing chain (if that is the problem). I use a large screwdriver to track noises and it might be worth a try. Good luck.

 

[Russ in CT]

I had a similar type of issue with a car once, and it turned out to simply be loose bolts connecting the flywheel to the TC. It was a deep down knocking noise. It was surprisingly loud and 'forceful', and sounded expensive (main bearing or a rod bearing, etc.)

I torqued the flywheel bolts back down, and haven't a problem since (60K miles+)

Something to check for before you spend the big $$$

 

[lramos3]

Just recently had a tapping noise from the engine in my '99. It ended up being the spark plugs I had installed (Bosch Platinum+4). When I removed the plugs it looked like the valve was hitting the tip of the plug. Went back to Motorcraft plugs and now I have no tapping noise.

 

[Aussie Explorer]

Is it a 4.0Ltr s.o.h.c

The noise you describe, the car sounds a little like a diesel engine when idling?
If so> Probably the timing chains or tensioner.
$4000 for the chains is the cost down hear as well, as the motor has to come out and it is a basted of a job. Do the tensioner first, that generally shuts them up for a wile around $650.
80% of the time you will have to do the chains sooner or later as they are weak.

The good news is that we have never herd of the chains parting ways and the motor going bang, but if they do you are looking at a big repair bill.

If it is a constant noise that dose not go away and everything else checks out.
BAD news you chains are probably stuffed.

 

[inkedbull]

I have the same problem. I can hear the noise in the engine compartment but it is much louder underneath. It kinda comes and goes, though, doesn't get any louder when I rev it. I'm way too broke to have it checked out right now.

 

[monkeydude3]

I assume we are talking about the OHC engine? I have the 4.0L OHV and I certainly don't hope these happen to me.