Timing chain tensioner the true story.....

[sport trac jr.]

I got the ...Oh for 2001 Ford ST bottom.....Ford part 6K254B... Well got it off and no washer.....Also so it
was super stiff......but how many miles that would be is why I put a new bottom tensioner on.

Question: I did not get the new one to pump up as hard as the old with pre-oiling it.....Is that OK
it will fill up when it runs????

Second: It did not have a crush washer.....and I could not find one...when to Ford place parts and ask for a
crush washer for the bottom tensioner part 6K254B and was given the Ford diagram of that area and it showed no
crush washer on the bottom one 6K254B no crush washer.... 6K254A the top tensioner had the washer....

Third: So it took a black marker and marked where the oil tensioner engine port is and then took painters tape and put
that on top on the tensioner part 6K254B and marked it on top with black line, so after I put in I could see it the 2 marks
lined up....and well they did....

So my main question if I did not get enough oil in the new tensioner part 6K254B it will pump itself up full
oil pressure in the tensioner......when installed.....please say YES....

 

[swshawaii]

The rattle usually begins at cold startup, but there are 2 different issues to think about. The hydraulic tensioners may become weak with age, but they're a crappy design needing oil pressure to do their job. I've taken to putting my foot to the floor on the gas pedal (which turns off the fuel injectors) and cranking the engine for 10 seconds or so before starting the engine when it's cold. This stops the noise at startup, because oil gets pumped into the tensioners.

4.0l Engine Timing Chain Tensioners, Replacement Schedule

Several years ago we lost the engine in our '02 S/T due to the timing chain tensioners failing (134K on the engine at the time). I'm wondering if I should schedule the tensioners for replacement at a specific time? Just as a preventive maintenance item. At the time of the engine...

www.explorerforum.com

 

[donalds]

did not get the new one to pump up as hard as the old with pre-oiling it.....Is that OK

Its fine

It did not have a crush washer.....and I could not find one...

I've seen people use no washer
I don't recommend that but it will work fine
Whatever you do don't put ANY kind of gasket maker/ sealant on It

 

[sport trac jr.]

Its fine


I've seen people use no washer
I don't recommend that but it will work fine
Whatever you do don't put ANY kind of gasket maker/ sealant on It

Donald....You're send out negative physic waves......again...Last time you did that I got a
ear ache.......See the attached Ford diagram.....no washer.....only top one has washer....
you put a washer on a non washer item is why I check to make sure
the ports lined up, with the washer ports might not line up..... This is a
Ford parts diagram.....See in the pdf 6K254B no crush washer.....
See 6K254A top shows crush washer.

 

[donalds]

I believe it needs a washer

Its a crush washer it is there to crush instead of the threads crushing
The gasket also had a rubber coating as well
sorry for the negative physic waves

 

[sport trac jr.]

I believe it needs a washer

Its a crush washer it is there to crush instead of the threads crushing
The gasket also had a rubber coating as well
sorry for the negative physic waves

View attachment 331988

View attachment 331989

What I posted was from the Ford dealer the PDF, was yours a act. Ford diagram. After I looked at the bottom
tensioner it looked like it did not have enough room for the washer because the port on the tensioner was right
on the rim of it. As I said I marked the block and tensioner and the lines matched when tighten.....The question
would the crush washer when tighten would it compress inline with the port???? Im going on the Ford diagram...
no crush washer shown.....I would like to know....which is right....??? on pdf part 6K254B no washer.

Thank Donald......

 

[sport trac jr.]

What I posted was from the Ford dealer the PDF, was yours a act. Ford diagram. After I looked at the bottom
tensioner it looked like it did not have enough room for the washer because the port on the tensioner was right
on the rim of it. As I said I marked the block and tensioner and the lines matched when tighten.....The question
would the crush washer when tighten would it compress inline with the port???? Im going on the Ford diagram...
no crush washer shown.....I would like to know....which is right....??? on pdf part 6K254B no washer.

Thank Donald......

The red arrow identifies the hole that allows pressurized oil to enter the threaded cylindrical housing. The oil pressure forces the plunger against a projection on the guide resulting in chain tension. The blue arrow emphasizes the short distance between the under face (idenitified by the green arrow) of the hexagon head and the start of the hole. Installing a thick compression O ring will partially (if not totally) reduce the internally exposed oil passage and restrict oil flow to the plunger. Only install the very thin metal seal designed for the tensioner. It is important not to score the under face and the mating face on the head where the metal fits. Potential leaks can be prevented by keeping the tensioner installed when working on the engine except when the tensioner is being replaced. The metal seal can easily slip out of position when screwing in the tensioner. Grease can be applied to the metal seal to keep it in position.

I recommend that the rear timing chain tensioner be replaced every 75,000 miles or whenever chain rattle is detected at the rear of the right head. Chain rattle usually is first detected at engine cold start because the oil has had time to drain from the timing chain components. As the tensioners age the internal spring pressure weakens and the plunger exerts less force on the timing chain. This allows chain slap until oil pressure builds in the tensioner. Chain slap accelerates guide wear. As the guides wear eventually the chain comes into contact with metal surfaces resulting in chain wear and metallic particle contamination of the oil. The metallic particles in the oil accelerate oil pump wear and can accelerate wear in engine bearing surfaces unless a high quality filter traps them. Typically the rear chain cassette lasts longer than the front cassette because upon engine start the rear cassette receives oil sooner than the front cassette.

 

[donalds]

Its not the spring that weakens
Its the one way valve and rubber seals that cause tensioner failure

If only someone made a video or a cutaway of the tensioners

Btw I got the diagram above from the ford service manual
It should have a gasket IMO take it or leave it
I would follow the fsm

Ford Timing Chain Tensioner Cutaway

Thought I'd post this. Thought it'd help someone. Any thoughts?

www.explorerforum.com

 

[sport trac jr.]

Its not the spring that weakens
Its the one way valve and rubber seals that cause tensioner failure

If only someone made a video or a cutaway of the tensioners

Btw I got the diagram above from the ford service manual
It should have a gasket IMO take it or leave it
I would follow the fsm

Ford Timing Chain Tensioner Cutaway

Thought I'd post this. Thought it'd help someone. Any thoughts?

www.explorerforum.com

I forgot, this all got started when I removed the bottom ten. and their was not a washer on it....then went to
Ford place and their diagram showed no tensioner in the Ford diagram, now that was for the 2001 matched
with VIn no. ford diagram.

I think it should have one, you cant order a crush seal for it you have to get one for the top tensioners and use on
the bottom one...I posted that cut away....You are right was the seal that gives out...and the ball valve...


thanks Don...

 

[swshawaii]

What I posted was from the Ford dealer the PDF, was yours a act. Ford diagram. After I looked at the bottom
tensioner it looked like it did not have enough room for the washer because the port on the tensioner was right
on the rim of it. As I said I marked the block and tensioner and the lines matched when tighten.....The question
would the crush washer when tighten would it compress inline with the port???? Im going on the Ford diagram...
no crush washer shown.....I would like to know....which is right....??? on pdf part 6K254B no washer.

Thank Donald......

the tensioner oil groove around the circumference allows oil to flow no matter what the orientation of the tensioner port relative to the head port.

97 SOHC Hydraulic Tensioner Failure?

Hey guys, First thanks to everyone who posts to these boards as you have saved me a lot of time and money. Now for my problem: I recently decided to go ahead and put a new hydraulic tensioner in the left head due to increased chain noise. Well, after installing it, the noise was much...

www.explorerforum.com

Front and rear tensioner gasket/crush washer/seal are the same part. XU2Z-6M252-AA

 

[sport trac jr.]

Front and rear tensioner gasket/crush washer/seal are the same part. XU2Z-6M252-AA

I actually think their should be a crush washer......just look at this removal of the bottom
one at 2:31 where their is no washer.....and why my Ford diagram did not show that bottom
crush washer?? weird.....dont get it.....this guy seems to think the bottom one seal without
a washer....not that he is a expert......Good point on flow around the tensioner...I did
mark block and tensioner port and when threaded back in they matched...??? just saying...

thanks SW.....Good point on flow around.....how did you come up with that..

 

[swshawaii]

"Oil groove" machined in the block came from one of 2000StreetRod's excellent threads. Definitely the resident guru of the 4.0L SOHC on EF.

2000StreetRod's Helpful thread list

Listed below are threads I've generated to try to help other Explorer owners: Starter No crank procedure Engine No Start Procedure PCM Power Procedure Lean condition procedure Engine misfire procedure TPS Test Procedure What's that on the fuel rail? Fuel Pump Electrical Procedure Fuel...

www.explorerforum.com

I replaced both hydraulic tensioners proactively at 78,000 miles that led to very different issues. Like yours, my rear tensioner did not have a gasket installed from the factory. Leaked until I torqued to a scary 65 ft/lbs. Got VERY lucky. In hindsight I should have been patient and ordered a gasket.

Front tensioner was a huge ordeal after inside threads were stripped when it was being removed. Intake interference skewing the 27mm deep well socket was the cause. Loosening the intake bolts 1/4" would have prevented the fear and grief of possible cylinder head replacement. M22 x 1.5 Heli-coil was a thought, but didn't find anyone who had done it. Luckily the front tensioner sealed with a new gasket at 50 ft/lbs, with compromised threads.

And yes, @donalds was a HUGE help with advice via PM's for my front tensioner dilemma. Also, his tensioner cutaway video ROCKS!!!

 

[sport trac jr.]

"Oil groove" machined in the block came from one of 2000StreetRod's excellent threads. Definitely the resident guru of the 4.0L SOHC on EF.

2000StreetRod's Helpful thread list

Listed below are threads I've generated to try to help other Explorer owners: Starter No crank procedure Engine No Start Procedure PCM Power Procedure Lean condition procedure Engine misfire procedure TPS Test Procedure What's that on the fuel rail? Fuel Pump Electrical Procedure Fuel...

www.explorerforum.com

I replaced both hydraulic tensioners proactively at 78,000 miles that both led to different issues. Like yours, my rear tensioner did not have a gasket installed from the factory. Leaked until I torqued to a scary 65 ft/lbs. Got VERY lucky. In hindsight I should have been patient and ordered a gasket. Front tensioner was a huge ordeal after inside threads were stripped when it was being removed. Intake interference skewing the 27mm deep well socket was the cause. Loosening the intake bolts 1/4" would have prevented the fear and grief of possible cylinder head replacement. M22 Heli-coil was a thought, but didn't find anyone who had done it. Luckily the front tensioner sealed with a new gasket at 50 ft/lbs, with compromised threads.

And yes, @donalds was a HUGE help with advice via PM's for my front tensioner dilemma. His tensioner cutaway video ROCKS!!!

View attachment 332101
View attachment 332102
View attachment 332103
View attachment 332104

Damn that's getting deep.....Question, so are factory first time replacements tensioners coming without crush washers????

Wow I just caught in your response......as follows "Like yours, my rear tensioner did not have a gasket installed from the factory"....This is weird.....so if you had put on the crush washer this over tightening thread issue
would not have happen...???

Im not fighting putting a crush washer on.....because Donald threaten me...possible doing
2 years "Ford Time"......in Detroit ......So Im chilling.....Im OK.....I can handle it......Did I say how
nice Donald's hair looks.......

thanks SW.............................Gray

 

[swshawaii]

Not deep, just info to prevent possible issues for the next guy. No reason NOT to use a crush washer. Even though the threads are somewhat large being M22x1.5, there is always a chance of stripping. Think spark plug threads and how often it happens in aluminum heads. As you've read, and should you decide to use a crush washer, perfect centering and a flat, clean sealing surface is the key to a good seal.

 

[sport trac jr.]

Not deep, just info to prevent possible issues for the next guy. No reason NOT to use a crush washer. Even though the threads are somewhat large (M22x1.5) there is always a chance of stripping. Think spark plug threads and how often it happens. As you've read, and should you decide to use a crush washer, perfect centering is the key to a good seal.

What the heck does that mean.....centering the washer on the tensioner, like whats that about and how is that
done....with grease as a bond and what keeps it from moving as its tighten??? Not really allot of room
to see up in their......Any time I have ever tried to center a washer that never works....in a tight spot.
Thanks......SW

 

[swshawaii]

Be patient and have good lighting. Also doesn't help that the tensioner's angled downward. Crush washer inside diameter is quite a bit larger than the flange on the tensioner. Use just enough heavy grease to keep the washer in place while tightening. If you look at my last pic above you can see what it looks like when sealed.

 

[sport trac jr.]

It is easier said than done. Be patient and have good lighting. Also doesn't help that the tensioner's angled downward. Crush washer inside diameter is quite a bit larger than the flange on the tensioner. Use just enough heavy grease to keep the washer in place while tightening. If you look at my last pic above you can see what it looks like when sealed.

So I was going to put the bottom washer on ......now...If its not leaking soon with out ....will it
leak right off the bat or later or never with out washer...
thanks SW

 

[swshawaii]

Huh? Please don't overthink this. It almost always starts leaking immediately after starting. Also, if you see leaking above the tensioner you have the all too common valve cover leak.

IF YOU HAVE THE REAR TENSIONER INSTALLED WITHOUT A LEAK LEAVE IT ALONE.

 

[sport trac jr.]

Huh? Please don't overthink this. It almost always starts leaking immediately after starting. Also, if you see leaking above the tensioner you have the all too common valve cover leak.

IF YOU HAVE THE REAR TENSIONER INSTALLED WITHOUT A LEAK LEAVE IT ALONE.

Right on SW.......thanks for that ......will check and see how it does......Gray

 

[sport trac jr.]

Right on SW.......thanks for that ......will check and see how it does......Gray

Donald ...thought you might want this for a "key chain or Ford necklace" Ebay selling a "used tensioner".....I hope
thats not for being installed......Get this its 33.00....bought a new one for 39.00