4.0L SOHC Metal Reinforced Timing Chain Guides Possible?

[swshawaii]

Reviving a copied and pasted thread from EF on January 27, 2017

Novice question. Must be a reason an aftermarket manufacturer hasn't made them. "If" the engine wasn't destroyed when the plastic tensioner guide(s) failed, seems like it would be a very lucrative business for those choosing to rebuild rather than replace their engine.

In my opinion the main deficiency with the Ford SOHC V6 4.0L design is not the use of plastic tensioner to chain wear surfaces but the use of plastic as a structural element. Due to heat cycles and mechanical stress cycles the plastic eventually fractures and then breaks. The cassette guide assemblies should have been built of metal with plastic only used for chain to guide wear surfaces.

https://www.explorerforum.com/forum...inforced-timing-chain-guides-possible.458231/

 

[swshawaii]

SportTrac.org 1/31/17

Original title read "4.0L SOHC All Metal Timing Chain Guides Possible?"
https://sporttrac.org/threads/4-0l-sohc-all-metal-timing-chain-guides-possible.119151/

 

[DILLARD000]

20 years ago, if Cloyes or Fords factory supplier
had chosen to make+sell MetalReinforced TimingGuides with CeramicCoatedSlides
to replace for the original\notorious brittle plastic FordMotorCraft TimingGuides,
that might have kept the V6~4.0L~SOHC & SportTrac in production much longer.

 

[curtis james]

i agree with your analogy but if ya know ford they stop production of vehicles way to soon and even there best line ups, i have a excursion, and a flex and love them along with my tracs. never could understand there reasons but all seem to have a short production run. my ex worked at ford for 20 years and they sold like hot cakes even at the end of there run. i still have the stock cam assembly in my 04s and i do think maintenance is key. although one only has 60k miles its still a 04 and been pushing 33x 12.5 20 from day one and no issues my other 235k miles and stock.

 

[Evox]

It's ironic that the timing cassettes are problematic on several different engines Ford designed or manufactured. The timing cassettes on the Range Rover L322's produced through 2012 are problematic as well. They are also problematic in some of the Jaguares using the same V-8 engine of the same era. (An engine Ford designed and manufactured with Jaguara and Range Rover).

Their problem isn't with the disintegrating plastic guides. It's with a small aluminum button on the guide rails themselves, which are met with steel spring-loaded tensioners. Obviously, over time the aluminum buttons lose out to the steel tension pins wearing away the aluminum buttons and causing slack and then failure. If driven to failure, it's catastrophic for those engines, and most of the time, there little or no warning. They typically wear out between 80k-125k miles on the clock. While the procedure to replace them isn't an engine-out operation, it's a bit of a pain in the ass. The manual says it's a 29-hour job and requires specialized tools to accomplish. The dealership will charge you around 10k to replace them, but you might get an independent to do it for $7k-8k. It's fairly labor-intensive and typically other components have to be replaced as well making it an expensive job.

In the first few years of the Sport Trac, Ford used some really crappy plastic on its timing guide rails that break apart over time. So same component but a different problem as the Range Rovers and Jaguars.

In the Sport Tracs, if the rail fragments don't block and starve off any oil ports inside the engine, a lot of time those engines can be saved without a rebuild if the owner catches it fast enough. Sometimes pieces will turn up in the oil pan. Mine is an '04; it's still running fine with over 300k miles on the clock. Sometime in late '03 or early '04, they changed the plastic they use for the guide rails.

The problem with the 4.0L SOHC engine is there is absolutely no way to replace the passenger side timing cassette without taking the engine out. Since the problem is with the plastic chemistry itself, I'm not sure a metal reinforcement would have done much good. ...maybe.

 

[Lester Durst]

Dillardooo. Thanks for the pictures. Could youtell us which one is for which side of the engine please?
Wife has a '02 S/T which we bought new, now has 245K on it. Lost the D/S cassette when the engine had 134k around the year 2009/2010. Had to decide what to do with then engine and made the call to replace the it with a Ford "reman" (Dealer did the work) as I was concerned about the rear (Pass side) cassette failing being it had 134k on it.

Do you all think that the "new" style cassettes were more than likely used in the Ford "reman" engines...at the year/time frame of 2009/2010 ?

Wife still loves "her" S/T and its in great condition (except the roof paint). I do regular maintenance/ repairs on the vehicle.

 

[DILLARD000]

Below are Left+Right TimingCassette pics denoted.
Sorry can't vouch for what revision of the Cassettes were used in your Reman Engine;
I'd hope the latest component versions available at the time it was assembled\rebuilt.
Many FoMoCo components have date stamps; the only real way to answer your question.

Recommend changing the two OilPressurized TimingTensioners every 75k~100kMiles;
while the Cassettes are the usual broken casualties,
the Tensioners are the root cause, as they gum up & weaken with Mileage\Time.

Left TimingCassette=Chain+Guides+Sprockets, Ford# 7u3z-6a257-a

Right TimingCassette=Chain+Guides+Sprockets, Ford# 4L2z-6m290-aa

 

[swshawaii]

Not to stray from the discussion above, but here's a common failure point for the REAR tensioner guide. Not an engineer, but looking at this pic believe metal reinforcement "may" have prevented failure. Interesting thread linked below, good reading.
https://www.explorerforum.com/forum...ic-guides-on-timing-chain.399121/post-3768685
EDIT- added "GUIDE" to avoid confusion. (Not hydraulic tensioners)

@DILLARD000
Thanks for adding the REAR "plastic tensioner guide from hell" pic in the following post. (#9)

Here's another. Oil looks VERY sludgy. Instead of low maintenance, call this NO maintenance. Pathetic.

And another from this interesting thread.
https://www.explorerforum.com/forum...rt-trac-250k-and-counting.478260/post-3753750

 

[DILLARD000]

Yep,
seems a little metal replacing plastic between the two sides of that guide,
would have prevented the break.

 

[Evox]

On the topic of timing chains, here is an interesting article from 2013:

"The redesigned Ford primary timing chain service kit includes an improved chain tensioner and chain guide, chain, jackshaft, and sprockets. Kit number 2U3Z-6D256-AA is for balance shaft engines in 1999 to 2001 4×4 Explorer/Mountaineer, 2001 to 2002 4×4 Sport/Sport Trac and all 2002 Explorer/Mountaineer (except engine codes 2G-960-AA and 2G-964-AA). Kit number 2U3Z-6D256-BA is for non-balance shaft engines in 1999 to 2001 2WD Explorer/Mountaineer and 2001 to 2002 2WD Sport/Sport Trac, and all 2001 to 2002 Ranger."

https://www.underhoodservice.com/exploring-service-needs-on-the-ford-4-0l-v6-engine/

 

[swshawaii]

^ Good article above with one glaring mistake.

"Fortunately, the 4.0L SOHC is not an interference engine so a timing chain failure won’t bend the valves."

Messaged them several times YEARS ago to correct or delete it. Ignored or just didn't care.

 

[swshawaii]

I wasn't the first. See "comments" in article.

 

[Lester Durst]

On the topic of timing chains, here is an interesting article from 2013:

"The redesigned Ford primary timing chain service kit includes an improved chain tensioner and chain guide, chain, jackshaft, and sprockets. Kit number 2U3Z-6D256-AA is for balance shaft engines in 1999 to 2001 4×4 Explorer/Mountaineer, 2001 to 2002 4×4 Sport/Sport Trac and all 2002 Explorer/Mountaineer (except engine codes 2G-960-AA and 2G-964-AA). Kit number 2U3Z-6D256-BA is for non-balance shaft engines in 1999 to 2001 2WD Explorer/Mountaineer and 2001 to 2002 2WD Sport/Sport Trac, and all 2001 to 2002 Ranger."

https://www.underhoodservice.com/exploring-service-needs-on-the-ford-4-0l-v6-engine/

Fellows... Any idea what year Ford introduced this "fix" with the "improved" parts?

 

[curtis james]

this is why i like this forum, great advise. evox you said 300k miles first off wow second what issues have you had and did you do your timing chain.

 

[Brett H]

My rear one broke like that on my job 1 2001. Had the engine pulled and a new complete cloyes timing kit put in it about 10k miles ago. Nice and quiet now. Now have about 155k on the truck.

 

[Fordtruckfan89]

The 03 I have had the updated parts, the front chain was fine, rear was broke to hell as was the spring tensioner on the front.

 

[Evox]

this is why i like this forum, great advise. evox you said 300k miles first off wow second what issues have you had and did you do your timing chain.

Over 17 years of ownership, I've had no issues with the engine or transmission. But of course, I've had to deal with maintenance items.

I've completely rebuilt the suspension twice. I replaced all the body bushings. Which whatever rubber Ford used for the B and C body bushing disintegrated fast. A and D were good, but I went ahead replaced them as well at the same time.

-replaced the instrument cluster once -- but currently experiencing some strange electrical problems
-replaced the ignition switch
-replaced the ignition key cylinder
-replaced the plastic thermostat housing once (I'd probably go with the aftermarket aluminum one had I to do it over again)
-replaced the AC compressor clutch once.
-replaced lower pan gasket, valve cover gaskets once or twice. I hate oil leaks.
-replaced the timing chain tensioners two or three times, I can't remember.
-replaced the alternator 2 or 3 times (I suggest spending the extra money for a Motorcraft alternator, my problems all came from cheap ones from Advanced Auto with "lifetime warranty, which was two in one year once)
-replaced other wear items, plugs, wires, bearings, brake pads, rotors, filters, fluids, etc.
-I had to replace the caliper pins once, but the calipers are still going strong with no leaks. Ford puts this rubber sheath on the caliper pin, and over time that loses grip slips off at the bottom of the caliper pin hole and can cause some weird braking shuttering. I had to dig mine out with a pick.

I do oil changes every 3k miles and replace the PCV valve annually (probably overkill I've never replaced one where the ball was stuck). I'm a stickler for fluid changes and have never bought into the long intervals some manufacturers recommend.

This is a southeastern rural truck. So no road salt and not a lot of city driving. It's been a good truck, except for my current electrical problem. I hate electrical problems worse than oil leaks, mainly because I feel like a blind man in a dark room when dealing with them.

-

 

[curtis james]

a lot of good info. i agree with the oil changes, i change way earlier then recomendations. when you can get 300 k miles out of vehicle thats amazing. so sounds like your maintenance has paid off. and good luck on that electrical issue, and i agree its a nightmare tracking down the cause or causes.

 

[Evox]

a lot of good info. i agree with the oil changes, i change way earlier then recomendations. when you can get 300 k miles out of vehicle thats amazing. so sounds like your maintenance has paid off. and good luck on that electrical issue, and i agree its a nightmare tracking down the cause or causes.

I'm at my wit's end on this electrical problem. With all their expensive diagnostic equipment and specialized training, when the Ford Dealership Techs couldn't replicate it or find anything wrong, how in the hell am I going to do it. Maybe the truck really is haunted.

At this point, I've installed quick-release battery terminals so I can disconnect the battery easily every time I park it. Not a fix. I'm not sure what I'm going to do.

 

[Todd Z]

Good old sport trac gremlins....
Synthetic oil goes along way too.... Warming up the engine, replacing hydraulic tensioners also "helps"
Planned obsolesce is a bitch....

As for the electrical, do a drain test until you find the circuit and diagnose. Easy really. Hell you could just unplug things over night and see.

Its normally the Rear amplifier staying on, Light in the glove box, Bad diodes int he alternator, bad battery, bad body module or the instrument cluster failure...… Also just because you replaced it doesn't mean its not bad again..

Fuse pull or unplug over night is the easiest trick.