look what I found in my oil pan! what is it?

[Austin Healey]

Removed the oil pan from my 1997 Explorer w/ OHC V-6 because it was leaking and discovered a piece of plastic in there! Pix are attached (I hope) -- top and side views. It's about 2" long.

I'm guessing that it's a piece of broken chain tensioner that somehow got down there. Any other guesses?

And assuming that is the tensioner (I've only owned the truck a few months, and probably covered less than 100 miles because I've been fixing stuff), is the fact that it's broken a bad sign for the engine? When driving, I thought the engine was kinda noisy -- could that be from a loose chain?

All comments, advice appreciated.

 

[colintrax]

Chain tensioner, sorry for the bad news.

 

[Tech By Trade]

Hey, thats the top of the passenger side guide. Its not really that important. Usually the first part that brakes off as they disintegrate. Search "Death Rattle"

 

[koda2000]

Yes, that's a piece of your chain tensioner. Sorry you bought a SOHC V6. We all learn the hard way (including me).

 

[Austin Healey]

I was all excited about finally buying a vehicle with a timing CHAIN, instead of a belt. Sigh.

How hard is it to get at the passenger side tensioner -- and if I'm replacing, assume I should do the driver's side as well? Are there any uprated tensioner components, or is plastic the only choice?

 

[koda2000]

I was all excited about finally buying a vehicle with a timing CHAIN, instead of a belt. Sigh.

How hard is it to get at the passenger side tensioner -- and if I'm replacing, assume I should do the driver's side as well? Are there any uprated tensioner components, or is plastic the only choice?

The tensioner or the timing chain cassette? For the cassette and chains the engine must be removed from the vehicle to do the passenger side. Big job.

The rear/passenger side tensioner is a hydrualic unit which works off engine oil pressure. The passenger side tensioner is fairly easy to change, but I doubt changing it will help you.

 

[Austin Healey]

I found a writeup for timing chain replacement -- http://www.explorerforum.com/forums/index.php?threads/sohc-v6-timing-chain-parts-removal-procedure.316471/ -- which had the photo below of the chain setup. Is my broken part likely the tensioner/guide for the balance-shaft chain at lower left? Does it matter if I don't replace it?

 

[Mr. Alligator]

I never could get a definitive answer regarding the deletion of the balancer shaft chain in a four-wheel-drive vehicle. The best estimate was that deletion would not be a problem, but I did not have the nerve. I just get thinking that the Ford engineers must have had a good reason to include the balancer.

If you do not delete or replace the balancer shaft chain, and the balancer shaft chain breaks or gets in trouble with the gearing, I doubt the engine would survive.

With the timing chain cover removed, it is fairly simple to replace the primary ("jack shaft") tensioner. However, balancer chain tensioner replacement requires removal of the upper oil pan, which seems to be somewhat difficult with the engine in the vehicle.

Good luck.

 

[CDW6212R]

That's part of the timing chain cassette, there are two, one for each camshaft/head. If the plastic is breaking, it's past time to replace them. The front one is a big job, and the special timing tool kit is required($150+).

Below shows the rear of the right head, the cassette which can only be changed with the engine or transmission out.
The next pictures show the front cassette, which runs between the left cam/head, and the jackshaft.

 

[Mazior R.]

Looks like a time chain guide(tensionor). Ours has been broken for years and is still driving. Our's has a rattle but isnt to loud. I wouldn't worry about it in my opinion but it's up to you if you want to fix it or maybe my guess is wrong, idk.

 

[boominXplorer]

If that's all you found you'll be just fine. It looks like the balance shaft tensioner or the very bottom of the drivers side timing cassette. Did you look in the pickup for debris?

 

[Austin Healey]

If that's all you found you'll be just fine. It looks like the balance shaft tensioner or the very bottom of the drivers side timing cassette. Did you look in the pickup for debris?

I didn't see any other debris in the pickup, but will doublecheck. If I hadn't needed to remove the oil pan, I never would have known there was an issue -- the engine sounds fine. This will be a relatively low-mileage vehicle, maybe a few thousand miles a year, and the truck has less than 70k miles (documented) and was ridiculously over-maintained (the stealer charged the PO (female) a ridiculous amount for everything, included service she didn't need, etc.)

My inclination is to do nothing. If the engine blows, then I would buy a rebuilt engine and install it myself (I'm a very experienced shade-tree mechanic.) Yes, I could pull the engine now and replace all the timing stuff, but the parts are expensive, I hate the idea of buying a $150 tool for one-time use, it's a lot of work, and it also sounds like it's easy to screw up the job.

I used to own a Saab turbo with much higher mileage that had also pretty much eaten its chain tensioner (you could hear the chain slapping around), and those things would go forever with loose chains (common problem). Admittedly, the chain layout was more straightforward than the Rube Goldberg setup with the Explorer engine.

Comments?

 

[CDW6212R]

Do the external tensioners at the least. Those cost maybe $100 tops, OEM only. Do not remove the temp sensors from the T'Stat, ever, they usually leak and cannot be resealed. The rear one is easy, just be sure the sealing washers are perfectly centered when installing. Those should be done every 75k, or sooner due to rattling.

 

[koda2000]

If it's not rattling yet, I won't do anything, other than maybe the external hydraulic tensioners. You'll get plenty of warning (it usually starts with rattling at start-up) before you'll need to replace timing chain components. As you don't plan on driving the vehicle much, I just suggest you get oil pressure up before allowing the engine to start. You can accomplish this by holding the accelerator pedal to the floor while cranking the engine (this turns off the fuel injectors). Crank the engine for around 5-8 seconds for the first start of the day before lifting your foot. That will build enough oil pressure to fill the tensioners and will also eliminate the annoying SOHC starting flare (high RPM immediately after starting). I've been doing this on my '01 ST for the past 3 years and the start-up rattle hasn't gotten any worse. I drive it around 5K a year.

As said, be very careful to center the washers on the new tensioners (I use a little grease to hold them in place) and torque them to spec or you'll end up with huge oil leaks and don't mess with the coolant temp sensors.

 

[boominXplorer]

I wouldn't touch the timing components at all, you could open up a can of worms just doing the external tensioners at this age.

 

[koda2000]

I wouldn't touch the timing components at all, you could open up a can of worms just doing the external tensioners at this age.

Actually I have to agree with you. The extra tension of a new tensioner might cause something to break. Probably best just leave them alone.

 

[CDW6212R]

That is like leaving old fluid in a transmission, being afraid to change anything. No, maintenance is more important than fear.

 

[Austin Healey]

Thanks for all the comments. I'm usually a member of the "when in doubt, replace it" school of auto maintenance, but in this situation I'm inclined to leave well enough alone -- at least until I start to hear more alarming noises (or the engine blows up, of course!).

 

[Austin Healey]

I checked oil pickup screen again before replacing new oil pan, and it was clean. Also, wasn't any debris in pan.

Still trying to figure out exactly what broke -- the left-side (as viewed from front) tensioner for the main timing chain, or the guide for the balance shaft chain.

If the part that is broken is what is shown below, that's available separately and also appears it's not activated by tensioners -- it's just a guide. Is it worth replacing? Also, is it possible to replace it without having to remove the tensioners, etc., for the main timing chain?

As usual, thanks for any advice.