Straight Talk on Timing Chain

[MrEvilPirate]

2002 4.0 in a 4x4 Edge Ranger with 152k.

I've read tons of threads about the timing chain rattle from bad tensioners and worn guides. Having a bit of trouble sorting it out. This was before I bought the truck. Now that I've lived with it a bit I'm starting to hear what I think is timing chain rattle JUST at startup, after sitting overnight, for about 1/2 second. No noise at mid RPMs or at a warm start.

I'm hoping replacing timing chain tensioners will fix this.

My understanding is there are 3 on the motor, 2 of which are accessible without pulling the motor, and luckily those are the most likely culprits.

I went to Ford and guy at the parts counter was unable to give me part numbers (??) for the tensioners. I know there was a TSB on the issue and a kit with a new tensioner and cassette was issued, but I think that kit was recalled and no longer produced, and I don't think Ford even uses the term 'cassette' anymore.

I want to fix it before it gets bad. Can someone give me part numbers for the two tensioners I can replace, and advise other things to replace without pulling the motor? I heard some talk about a pre oiler that I assume would pressurize the tensioners before startup. Since I'm catching this soon do you think my chain guides are still ok?

Also heard about a "flooded engine start" where you hold down the gas and crank, supposedly engine won't start and this lets you prime the tensioners. Is this for real?

Have had good luck on this site getting help in the past maybe I'll be 3 for 3 now. Thanks guys.

 

[gw33gp]

I bought mine many years ago from Tasca Ford online. I looked at their website and they don't show them under engines. I went to Rock Auto and they do list them but I don't know if they are quality parts. They are branded as Cloyes. I got the Ford part numbers from them and went back to Tasca. They did show up under a search. They are listed as timing belt tensioners at Tasca. They look like the same thing I installed. They are listed as timing chain tensioners at Rock Auto. They are a lot less expensive a Rock Auto but I am concerned about quality.

The Ford part numbers I found are 7U3Z-6K254-A (right) and 7U3Z-6K254-B (left). I can't confirm they are correct but look to be the right parts.

 

[alwaysFlOoReD]

Cloyes is a well known high performance timing chain manufacturer and has been around for decades. It's my go to for hi-po chains for my 429/460. I've bought and installed 2 sets in two different motors in the last six months. That said, lots of high end brands have out sourced manufacturing to off shore and quality can drop drastically, look at Sears. AFAIK Cloyes is still made in USA.

 

[MrEvilPirate]

GW - Thanks for part numbers. I googled them and got taken to Amazon as a first hit. They are the same I was looking at but unsure, your response makes me more confident. Funny- Amazon has them as "Timing Belt Chain Tensioners".

AF - Appreciate the input, but I think I will stick with Ford parts this time around... heard too many stories about aftermarket tensioners not working out. The outsourcing is real. I have a VW powered sand rail and it is unbelievable how many crap Chinese parts there are out there... OE German parts that are 45 years old outperform the new stuff by a large margin.

Anybody have torque specs for installing these?

Thanks fellas.

 

[RonD]

Yes, "Clear Flooded engine" mode works, prevents engine from starting so oil can be pumped through engine before start up.
I use it all the time on high mile engines, always good to get the oil circulating before startup.

As adsm08 has explained the original 4.0l SOHC engine timing chain tensioner design had flaws
Weak springs caused less tension on startup, before oil pressure took over
And oil pressure tension also lessens over time
Newer design is suppose to eliminate both issues.

The timing chain and guides were not the problem, per se, but as tension on the chain lessened it would start to beat on the Guides, damaging them, until they couldn't hold chains in place so you heard a Rattle.
Usually the rattle means some damage has already happened.

But you need the newer design tensioners in any case, so still worth while replacing the 2 on the longer chains.

Torque specs
Timing chain tensioner (hydraulic/spring):
...Thru 1998: Left: 35 to 39 ft-lbs, Right: 31 to 33 ft-lbs (Haynes)
...1999 & later: Left & Right: 49 lb-ft if reusing O ring, 32 lb-ft if new O ring (E/MWM)

 

[85_Ranger4x4]

Everything is totally different but I have had 0 issues with the Cloyes double roller timing chain in my 302.

They are a really old brand, chain was US made, I wouldn't be afraid of them for my 5.4 if I needed to go down that road.

 

[AllanD]

GUYS, PLEASE!!! He is discussing the timing chains on a 4.0 SOHC which it a completely discussion from the simple timing chain on a 302!

 

[MrEvilPirate]

Allan - I think he was speaking to the overall quality of Cloyes parts, not specific application... at least that's the way I took it. BTW love the Muslim/Gun Owner double standard in your signature right there with you.

You guys really think I've got damage? The rattle is barely noticeable at startup. I'm doing flooded engine trick every morning at cold start now until I get the replacement tensioners. I'm hoping the rattle goes away and I can get another 100k out of this truck. Is cassette replacement difficult or just time consuming? I wanted to do water pump and change coolant as preventative maintenance anyway, maybe I'll do it all at once. I think I need to pull (almost) water pump to do one of the tensioners anyway.

Appreciate all the good advice here. Thanks guys.

 

[alwaysFlOoReD]

speaking to the overall quality of Cloyes parts

yes.

 

[RonD]

The damage may or may not be "too far along", doesn't matter really since you can't do anything about it at this point in time, what's done is done.

Installing the new tensioners should make the rattle stop, and that may be the end of it for 200k+ miles, no crystal ball here

My comment was meant to reinforce the idea of changing the tensioners sooner than later.

Noise is "wear", parts are banging together to make that noise, how much "wear" a part can take is an unknown