URGENT! - ID this part - timing chain tensioner

[Russ in CT]

These bits were recovered from my oil pan. 4.0 SOHC, '99 Explorer. Which tensioner are they from, jackshaft or balancer? Who pays for my new engine hangs in the balance.

I had a local shop do the TSB kits to replace the jackshaft tensioner (whatever else comes in that kit, chain and gears?), front tensioner (tensioner, restrictor, intake o-rings), plus the rear tensioner. First few days, quiet engine, third day I get a LOUD clanking sound around 3K rpm's. Can't hear much at idle, but crank up the revs and it sounds ugly.

So the shop drops the pan and finds these bits, some lodged in oil pickup blocking the flow, certainly damaging the engine. They are saying the noise is the rear chain (plus some preexisting rod knock), and its just my bad luck that it went right after spending the bucks on these unrelated repairs. They are saying the parts pictured are either from some part of the rear guide, or the jackshaft tensioner.

I disagree, I think its from the balance tensioner, that an errant tool knocked it during the jackshaft repair, and it let go a few days later. They say no way. Bear in mind they never test drove it before the repair, so they have no reason to state any problem existed before, but they did test drive it right after, and didn’t note any problem. Yet they insist the noise must have been preexisting.

Since we can’t be sure who is right without an expensive tear down, I offered to split the cost of installing a used replacement engine. Shop instead says they want to tear down engine, if the parts are the balance tensioner, they’ll pay for the used replacement engine, otherwise I pay, plus their time for tearing down engine.

Before I agree to that I want to have a better idea of what these pieces are. The spring steel pieces measure 3 3/8” in length, 9/16” wide. The small plastic piece is just a tick over ½” wide.

Does anyone have an old jackshaft and/or balance tensioner they could take some close-ups of? (or even just measurements) Something that shows the tip, the head of the plastic ‘bow’ that tensions the chain? (to compare with the plastic piece shown here).

From looking at all the posted photos I could find, I'm pretty sure my piece is shaped differently the comparable piece of the jackshaft tensioner, but I just can’t be sure.

I need your help!

 

[Silver X]

Here's a pic of the primary tensioner. That plastic piece looks like the tip of the this tensioner, but has a couple of minor differences. Can't find a pic of the rear tensioner.

 

[Russ in CT]

Saw that pic, its what made me think its either jackshaft or balancer. But this closeup of jackshaft shows the tip is a bit different than my piece. That could just be production differences, but I think the key is the width. The jackshaft chain is much widere than the balance chain, so the plastic tensioner that presses against the chains would be different widths.

What I'd really like to see is those measurements. My piece is just over 1/2" wide (side that presses against chain). How wide is balance chain tensioner and jackshaft tensioner (plastic parts, side that presses against chain)?

Anybody know?

 

[donaldthacker]

you have a broken balance shaft tensioner. I have the exact same one, in pieces sitting on my work bench right now. I found mine laying in the pan as well. the jackshaft tensioner is much larger than the pc you have.
I ordered the tensioner from ford it was less than $30. the problem is putting it in is a real pain

 

[Russ in CT]

THANKS!

If its the balance tensioner, I get a free engine, so I'm not worried about how hard it is to replace. Some of these peices were lodged in the oil pickup, some of them still are lodged in there and won't come out. Oil flow was restricted, so the concern is bearing damage, etc.

The shop says if new engine noise is a result of their work (they replaced jackshaft tensioner and other parts), they'll pay for a replacement engine, if not, I pay for engine, their work to swap, plus their work to tear down old engine to see what happened.

My theory all along was that in replacing jackshaft they messed up the balance tensioner (errant tool, old, fragile plastic), but they say that isn't possible.

But I really, REALLY need to be sure this piece is from the balance tensioner, as I just paid $1700 for the jackshaft (and other stuff) repair, and can't afford to buy an engine, plus a ton of labor on top of that.

Can you take some closeup photos of your tensioner pieces? Maybe a measurement of how wide it is (side that presses against chain)?

 

[CDW6212R]

you have a broken balance shaft tensioner. I have the exact same one, in pieces sitting on my work bench right now. I found mine laying in the pan as well. the jackshaft tensioner is much larger than the pc you have.
I ordered the tensioner from ford it was less than $30. the problem is putting it in is a real pain

Are you sure about it? I have not seen my parts in over two years, but it looks too wide for the balance shaft tensioner.

I hope you can get some help with the repairs.

FYI, the balance shaft tensioner is extremely fragile. Mine was not broken when I first did my engine work, but before doing the timing chain it broke. I don't know what did that, but it likely didn't take much force. The parts are small, and being a combination of plastic molded around steel, they cannot take much force. Good luck,

 

[Russ in CT]

OK, so one vote for balance tensioner, one for too wide, must be the jackshaft tensioner.

HELP! Can someone measure how wide either the balance tensioner or jackshaft tensioner is (part that presses against chain)!

I really, REALLY need to know...

 

[BubbaFL]

Here are a couple pics of a primary chain tensioner - hope this helps.

 

[Russ in CT]

Thanks! That helps a lot! It would appear the jackshaft tensioner is as wide as a dime, which it turns out is about 11/16". My piece is about 1/2".

Of course, that is a photo of a new tensioner, and presumably they beefed it up over the original, but I wouldn't think the part that presses on the chain would be any different sized.

A lot hangs in the balance for me, so if anyone else has any other info to weigh in with, please don’t hold back!

Thanks guys!

 

[Russ in CT]

Still looking for photos or measurements of 'old' parts, jackshaft tensioner & balance tensioner, to compare to pieces recovered from my oil pan. Not yet willing to make a ~$2,500 gamble that my parts are certainly from the balance tensioner (shop pays or I pay).

The most helpful photo was of a new jackshaft tensioner. It clearly is wider than my recovered part. But this is an 'improved' design part. Still uneasy about absolute certainty that an 'old' design jackshaft tensioner isn't different, that my part couldn't still be from a jackshaft tensioner.

Any help appreciated!

 

[CDW6212R]

My new parts looked almost identical to the old ones. They were the same in basic dimensions.