Help with timing chain parts for v6 SOHC 4.0L

[Addicted]

Hello, I'm next in line for that dreaded timing chain replacement. I spent a great deal of time watching videos and reviewing some helpful posts including the helpful engine removal guide posted by 2000StreetRod some years back.


I would like to slowly start ordering the parts necessary to get this engine back on the road. I saw a few kits being offered online and wanted to steer clear from any cheap parts. I want this to be a one time job.

I found this Melling Timing Chain and component kit on RockAuto

MELLING 3398S Timing Chain Kit


I'm not sure if this is a good option? From what I have been reading, it seems like it's been highly suggested that using original Motorcraft parts would be best.

Is Motorcraft still making all these parts?

Does anybody happen to have Motorcraft part numbers and or links to where I can find the parts required to replace all timing components?

I'm looking to replace both front and rear timing chain cassettes, tensioners, guides sprockets, chains, jackshaft bolts, etc.

I'm almost tempted to replace the rings and bearings while I'm in there.


The vehicle specs are noted below;

1999 Mercury Mountaineer (xerox copy of the Ford Explorer)
V6 4.0L SOHC AWD 4X4
176063 Miles

I presume I have the balancer since this is a 4x4. Is this correct?


I included some photos showing both sides of the engine with the valve covers off. The front chain is still tight despite the broken piece on top. That broken piece must have fallen inside the engine.

The rear chain cassette was totally broken apart. The third photo shows the amount of slack I had on that rear chain. That rear upper cassette bolt is also a bit dinged up from the belt slapping on it. Again, the broken pieces are inside the engine.

Any help, recommendations, suggestions would greatly be appreciated. This will be the first time I attempt to do anything like this in this car. I have rebuilt a few Chevy small block single cam V8 engines back in the days but the timing replacement procedures were nothing like this. This is seriously ridiculous.

 

[C420sailor]

We have some guys on here who like Melling, I think.

Me? Ford OEM or nothing. This isn’t a job you want to do twice. But once cry once. They aren’t Motorcraft parts, they’re Ford OEM (blue/white box)—dealer parts.

Avoid Cloyes unless you want to grenade your engine.

 

[donalds]

I like Melling
But only ford hydraulic tensioners

 

[Addicted]

They aren’t Motorcraft parts, they’re Ford OEM (blue/white box)—dealer parts.

Thanks for clarifying the parts. I thought Motorcraft produced OEM parts for Ford. If Motorcraft was to have produced these parts would they also have been considered OEM?

I came across a helpful post on here by 2kstreetrod who listed the Ford OEM timing chain related part numbers. I spent the past few days going over all the parts and understanding what I need to get this done.

I did find all the original parts I needed and notice that the parts seem to be all Ford OEM parts (blue/white) box as you mentioned.

Avoid Cloyes unless you want to grenade your engine.

Thanks for the tip.

 

[Addicted]

I like Melling
But only ford hydraulic tensioners

I decided that it's probably best if we stick to Ford OEM for all our parts.

Looks like I can get all the Ford OEM parts needed (purchased individually) for about $500 before tax. Close to the same pricing I saw offered for the Melling Kit.

That price also included a few other pieces not included in the Melling Kit.

 

[Addicted]

I have a question, I saw some complete aftermarket kit's that offered a part called "volume reducing plug (looks like a plastic rod) and the oil galley plug. Should I replace this?

Looks like ford has a kit for this also, YL2Z-9E473-AA

It also includes the front tensioner.


Also is it a good idea to replace any of these sprockets while I'm in there?

inner and outer crankshaft sprockets
front jackshaft sprocket
balance shaft sprocket

 

[C420sailor]

That rod, as far as I know, became standard in later job SOHC engines. I got my SOHC out of a 2010 ranger, and it already had that rod installed in it. With 36k on it, I doubt it was added by someone.

The idea is that it allows the tensioners to pressurize more rapidly. If you plan to use hydraulic tensioners, I’d install it.

If you decide to go with mechanical tensioners, it isn’t necessary.

 

[sehaare]

I decided that it's probably best if we stick to Ford OEM for all our parts.

Looks like I can get all the Ford OEM parts needed (purchased individually) for about $500 before tax. Close to the same pricing I saw offered for the Melling Kit.

That price also included a few other pieces not included in the Melling Kit.

That really is the way to go, something this big you don't want to always be second guessing yourself if you had went cheap. Peace of mind is worth the extra price and it looks like it isn't even going to be costing you anything extra.

 

[Addicted]

That rod, as far as I know, became standard in later job SOHC engines. I got my SOHC out of a 2010 ranger, and it already had that rod installed in it. With 36k on it, I doubt it was added by someone.

I went to check my engine to confirm and it does look like I have that "oil galley plug". It's at this location besides the front tensioner (as shown in the photo).

Without yet removing the plug I'm guessing the rod should be in there?

This engine did come equipped with hydraulic tensioners mounted on the heads. Which i presumed are standard? I'm not familiar or aware of any mechanical tensioners except for the ones that are used for the jackshaft chain and the balance shaft chain.

 

[Addicted]

That really is the way to go, something this big you don't want to always be second guessing yourself if you had went cheap. Peace of mind is worth the extra price and it looks like it isn't even going to be costing you anything extra.

For sure, I'm strongly leaning in that direction now. Ford OEM it is. I want this to be a one time job and never look back again.

I'm now contemplating if I should just change the rings and crank bearings as well while I have the engine pulled.

 

[C420sailor]

I wouldn’t, unless you have numbers showing your compression going. These engines have solid bottom ends. If you had 300-400k then that would be a diff story.

Yeah hyd tensioners are normal. Mechanicals are an upgrade guys do here. Yes, you can pull that oil plug easily to check for the rod if you want.

 

[Addicted]

I wouldn’t, unless you have numbers showing your compression going.

I might be overthinking it, but I wouldn't mind doing the job, especially being that the engine will be on the stand. A little more driving and we'll be at 200k in no time.

I have two more cars to keep us moving. So the downtime wouldn't be so disruptive.

I'll pull a compression test and check what numbers I get back. For this 4.0L SOHC, were should the numbers be? Around 150psi?

Yeah hyd tensioners are normal. Mechanicals are an upgrade guys do here. Yes, you can pull that oil plug easily to check for the rod if you want.

Thanks for letting me know about this. I don't know much about the mechanical tensioners.

So it's not unusual to have the oil plug and not have had the rod (on the 99 year)?

 

[C420sailor]

My ‘98 engine didn’t have the rod from the factory. My ‘10 did. So it was added sometime after ‘98.

It comes in the 00M12 kit, so it is designed to be added to engines without it.

If you don’t have the rod installed, I’d recommend installing it if you want to run hydraulic tensioners.

That said…if you’re doing all this work, I’d seriously consider going mechanical. Then you never have to worry about it again….

 

[Addicted]

It comes in the 00M12 kit, so it is designed to be added to engines without it.

Is the 00M12 Kit the same as the YL-2Z-9E473-AA? Is this what the 00M12 Kit is referring to?

if you’re doing all this work, I’d seriously consider going mechanical. Then you never have to worry about it again….

Not familiar with the mechanical tensioner at all. Is there any performance gain? I don't understand what the benefits would be if any?

Does the mechanical also screw in place of the existing hydraulic tensioners onto the heads? This would be for both front and rear?

 

[Fix4Dirt]

Solved - SOHC V6 Timing Chain Related PNs

Listed below are Ford part numbers for SOHC V6 timing chain related components. I try to keep this list current. Two possible discount online Ford OEM suppliers are tousleyfordparts.com and tascaparts.com Jackshaft/primary timing chain kit 2U3Z6D256CA includes: Crankshaft bolt harmonic balancer...

www.explorerforum.com

 

[Fix4Dirt]

Is the 00M12 Kit the same as the YL-2Z-9E473-AA? Is this what the 00M12 Kit is referring to?



Not familiar with the mechanical tensioner at all. Is there any performance gain? I don't understand what the benefits would be if any?

Does the mechanical also screw in place of the existing hydraulic tensioners onto the heads? This would be for both front and rear?

hydraulic tensioners when they run out of oil (to hold pressure on the chain) become loose and until you have oil pressure you have chains slapping around which is what breaks guides. with mechanical tensioner its set and forget, pressure on the chain will be the same, reducing (or elimination?) chain slap. the 00m12 rod does a similar thing by trying to keep oil from draining back, but mechanical is one step above. they bolt in the exact same spot and theres an install procedure that i dont know off hand @410Fortune is the knowledge on this subject. afaik there are tensioners for a polaris that bolt in.

 

[Fix4Dirt]

I wouldn’t, unless you have numbers showing your compression going. These engines have solid bottom ends. If you had 300-400k then that would be a diff story.

Yeah hyd tensioners are normal. Mechanicals are an upgrade guys do here. Yes, you can pull that oil plug easily to check for the rod if you want.

ditto. these motors are really strong on the bottom. at 330k and as of 310k the cylinder still had crosshatching... havent taken bearings off for wear scars... since the motor hasnt ever been pulled!

 

[C420sailor]

yeah, hyd tensioners rely on springs to take up slack on start, until oil pressure builds. That’s when chain slap tends to occur, eventually shattering the old cassettes and guides.

The mechanical tensioner mod ensures the chains are ALWAYS properly tensioned.

 

[Addicted]

Thanks for that posting Fix4Dirt. I did find that here shortly after my initial post. 2000StreetRod provided some immensely helpful posts on this forum. That post was about 13 years ago. Looks like he hasn't be on here in a while. Hope he's OK.


And thank you for explaining how the hydraulic tensioners work. So if my engine is using hydraulic tensioners and I don't have that rod under the oil galley plug, I could be stressing out my guides.

What an inferior design those hydraulic tensioners can be. I haven't opened the oil galley plug in my engine yet but that would be ridiculous to not have the rod in there from the factory to help prevent or minimize the impacts of the chain slapping onto the guides. Like why would the factory have the oil galley plug on this engine and not bothered to include the rod.

Would love to learn more about this. Sounds like otherwise we could stand a chance of encountering this all over again (even if using Ford OEM).

 

[Addicted]

The mechanical tensioner mod ensures the chains are ALWAYS properly tensioned.

This is so interesting to learn about. Is there a write up about this? How can learn more?

Were do I get the mechanical tensioner from and what's the process of getting this to properly work in my engine?