failed (aftermarket) tensioners

[NightmareMoon]

Put in some aftermarket one-piece timing chain tensioners while the motor was out and we were upgrading some other things. Well, it didn't work out. ~200 miles and we've got a mess to clean up. Stringyplastic fiber crap, mostly contained to the timing cover area.

Did a pretty good job clogging the up the oil filter, but I noticed it wasn't making the right pressure and parked it until we could investigate. Hopefully we might have caught it in time? Will see how it goes.

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[Cobra Jet]

Care to mention the brand of aftermarket tensioners so others can sway away from them?

 

[robvas]

Don't the modular techs on YouTube that do all the timing replacements say not to use any aftermarket stuff?

 

[NGOT8R]

This timing chain tensioner business is getting scarier and scarier! I‘ll say that is has caused me to make a hard pass on any of them at this point. Needless to say, I’m gonna stick with OEM and if anything, maybe only upgrade to Boss tensioner arms and tensioners.

Any plan on how you might go about flushing all of the oil passages to make sure they’re free of debris? I wish you the best coming out of this. It could have happened to any of us that upgraded. Those things obviously don’t like the heat very well.

 

[NightmareMoon]

Care to mention the brand of aftermarket tensioners so others can sway away from them?

Li Tuning. I wanted to gather more information, and to ensure it was not a problem with the install or with the Ford tensioners we swapped in at the same time, but I have enough confirmation now to share.

Don't the modular techs on YouTube that do all the timing replacements say not to use any aftermarket stuff?

IDK, do they? Sounds like good advice. These were supposed to be a durable option. They were not. Got a link to that video?

 

[SheepDog]

Care to mention the brand of aftermarket tensioners so others can sway away from them?

Sai Li Tuning

 

[NGOT8R]

@NightmareMoon the chain is almost buried into the arm, when it should be riding on top of it. I found this info as well to show temperature tolerances on polymer and materials.

Thermal

Because Delrin does not use plasticizing to attain its toughness, it does not suffer from brittleness at low temperatures. Its impact resistance at temperatures as low as -40° F is only 20% less than its resistance at room temperature.

For elevated temperatures, Delrin retains excellent strength at temperatures as high as 200° F with a tensile strength of 2,000 psi and flexural modulus at 180,000. Delrin’s upper service temperatures are 180° F in open air and 150° F in water and can withstand brief temperature peaks of 250° F.

 

[WItoTX]

Ugh man, I hadn't seen much posting from you lately, sorry to hear this! Brutal after all the other work put into that car the last 6 months or so.

 

[robvas]

IDK, do they? Sounds like good advice. These were supposed to be a durable option. They were not. Got a link to that video?

https://www.youtube.com/@FordTechMakuloco

He's 5.4 focused but I'm sure a lot of that applies to aftermarket Coyote parts as well

 

[SheepDog]

JPC racing and TKM performance also sell these guides without liners.

RGR- Coyote Primary Guides High Temp Street Tensioner Arms - Justin's Performance Center

Coyote Upgraded Primary Tensioner Guides | TKM Performance

 

[NightmareMoon]

This timing chain tensioner business is getting scarier and scarier! I‘ll say that is has caused me to make a hard pass on any of them at this point. Needless to say, I’m gonna stick with OEM and if anything, maybe only upgrade to Boss tensioner arms and tensioners.

Any plan on how you might go about flushing all of the oil passages to make sure they’re free of debris? I wish you the best coming out of this. It could have happened to any of us that upgraded. Those things obviously don’t like the heat very well.

Well, the stringy slime stuff was generated on the front timing area. Most of it which wasn't wrapped around the timing gear seemed to have gotten caught at the oil pickup screen.. Boy that oil pan pickup was clogged up worse than a toilet after a taco bell dinner. I think the oil filter caught the rest.

The oil pump looked ok, but its getting a new Ford pump and pan just in case. The passageway from the pump to the oil filter will get cleaned. We think the rest of the oil passageways are clear (timing chain mess->pan->pickup/screen->pump->filter adapter->filter->oil cooler->engine passageways)

Some glitter in the pan. None of it magnetic (so probably bearing material). We found minor wear on most main bearings but one rod bearing was pretty bad. Unsure if the glitter pre-dated this issue (the motor was a used 38k mile motor out of a wrecked car) or if the bearing damage was caused in part by oil starvation from it, but the motor is getting new bearings now too.

 

[NGOT8R]

Haha! I like that Taco Bell analogy.

Dang man! Way to go on your examination though. While you’re at it, are you gonna deglaze the cylinders and install new rings? You’re basically rebuilding that mofo. A lot of heat made short work of those tensioners.

 

[NightmareMoon]

Haha! I like that Taco Bell analogy.

Dang man! Way to go on your examination though. While you’re at it, are you gonna deglaze the cylinders and install new rings? You’re basically rebuilding that mofo. A lot of heat made short work of those tensioners.

This whole thing started with a spun bearing on my coyote, and I went down a rabbit hole trying to take an opportunity to upgrade to the 5.2 & Tremec and now we end up back at replacing bearings which is basically where we started.

A lot of upgrades to every other part of the car though between then and now, so its not exactly ending where I started, but this irony isnt lost on me.

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