4.0 SOHC. Replace timing or Not?

[4.0SOHCTX]

I have a RWD, 2001 ford explorer sport, with the 4.0 SOHC engine, that has about 195k miles on what I assume is the original trans and engine. I inherited the truck from my late mother. I have put the last 15-20k miles on it with minor issues but now I have a nice clear rattle at cold start from the timing chains and don't know whether to keep driving it as is or replace it. Love the truck but I'm unsure so I need some advice.
Question 1. Is it worth fixing?
Question 2. Do I get the best or cheapest Kit if I choose to fix it?

Also, I have a mechanic willing to pull out the engine and replace the chains, guides, and tensioners for $500 labor.
Thank you, any advice is greatly appreciated!

 

[koda2000]

This job requires a huge amount of labor, as the engine must be removed to replace the passenger side components. With parts you looking at about $2000+ to have this job done. If I were to do this job, I'd only buy the best parts available.

I'd be suspicious of anyone willing to do this job for $500 labor. It's a lot of work and many mechanics won't touch a SOHC.

Is it worth doing? That's up to you, but what if the transmission is next to need rebuilding? That's another $2000 plus job. I'm assuming the truck cost you nothing, so to keep it maybe $4000 isn't too much to put into it. Does it have sentimental value to you? How's the body and frame rust-wise? How's the interior?

I have a very nice, clean, rust-free 2001 V8 Eddie Bauer. It has almost 200k on it now. The interior is perfect, the paint is near perfect. if the trans or engine quit on me I just might spend the money to keep driving it. It's one of the best vehicles I've ever owned.

 

[Paul Fithian]

Use Koda's cold start up procedure to pressurize the hydraulic chain tensioners so that you don't get chain slap on cold starts:

1) Press the accelerator all the way to the floor
2) Crank the engine until oil pressure registers on the idiot gauge. Keep the engine cranking
3) Lift your foot off of the accelerator, the engine will start normally

Once it it warmed up, you don't need to use this procedure on restarts.

You may find that it runs a very long time this way. Mine has ~265,000 miles on it, still runs great. No abnormal oil consumption and great power. As far as I can tell, it is the original engine.

 

[koda2000]

Use the cold start up procedure to pressurize the hydraulic chain tensioners so that you don't get chain slap on cold starts:

1) Press the accelerator all the way to the floor
2) Crank the engine until oil pressure registers on the idiot gauge. Keep the engine cranking
3) Lift your foot off of the accelerator, the engine will start normally

Once it it warmed up, you don't need to use this procedure on restarts.

You may find that it runs a very long time this way. Mine has ~265,000 miles on it, still runs great. No abnormal oil consumption and great power. As far as I can tell, it is the original engine.

Yep, I kinda started this procedure (poor mans pre-oiler) on my '01 Sport Trac 4.0L SOHC. I do it every time I cold-start the engine. 212K+ and still gets me around town. I'm planning to drive it this way until it finally dies. Then I have to decide what to do with it. Who knows? It might outlive me, LOL.

 

[4.0SOHCTX]

This job requires a huge amount of labor, as the engine must be removed to replace the passenger side components. With parts you looking at about $2000+ to have this job done. If I were to do this job, I'd only buy the best parts available.

I'd be suspicious of anyone willing to do this job for $500 labor. It's a lot of work and many mechanics won't touch a SOHC.

Is it worth doing? That's up to you, but what if the transmission is next to need rebuilding? That's another $2000 plus job. I'm assuming the truck cost you nothing, so to keep it maybe $4000 isn't too much to put into it. Does it have sentimental value to you? How's the body and frame rust-wise? How's the interior?

I have a very nice, clean, rust-free 2001 V8 Eddie Bauer. It has almost 200k on it now. The interior is perfect, the paint is near perfect. if the trans or engine quit on me I just might spend the money to keep driving it. It's one of the best vehicles I've ever owned.

The mechanic is a great friend, is reputable, and is willing to do the work for $500, since he asked me to get quotes and said he'd do it for half that's the price we came to. His answer was "I guess" lol. 1-2k is about what I was getting quoted around town.

So far the transmission is seemingly running smooth, sometimes it'll give a light bump/kick when I give it hard gas and then let off the gas right when it's shifting.

The truck does have some sentimental value to me, it has had major hail damage to the roof and hood, basically all over since it was in an East Texas tornado. Minor rust on the rooftop and by one wheel well, but no frame rust. The interior is good, not great, minor things like the driver power seat only half work and passenger seat won't lean because the steel wire snapped under the handle, I also removed the rear door panel because there was no handle to open the hatch.

Since acquiring the truck I have done the following maintenance/upgrades to get it in decent mechanical shape:
(All new)
1. Radiator
2. Alternator
3. Shocks
4. Brakes (front and back pads+rear rotors)
5. Spark plugs
6. Spark plug wires
7. Ignition Coil pack
8. Valve Cover Gaskets
9. All 6 injectors
10.Thermostat housing
11. Fuel pump
12. Fuel filter
13. High mileage oil change (k&n filter+lucas)
14. Aftermarket Cold air intake (cheap ebay)
15. Sway bar links
16. 4 new tires
17. Tinted all around

The timing job can be done for $500 guaranteed, I just need to decide on the kit to order if I choose to do so.
Love the truck and still has good power and gets me around town no problem.

She also has a misfire/rough idle that I have been trying to get rid of hence all the ignition and injectors being replaced. I was told the timing slack could possibly cause a misfire, then I heard the so-called "death rattle" this winter when cold starting, in the front and back, so I'm sure the guides and tensioners are worn out.

 

[koda2000]

The front timing chain components can be replaced with the engine still in the truck. So if that's where you noise is you might start there. The hydraulic tensioners can be replaced fairly easily, but will more than likely not offer any improvement.

I wouldn't buy any other brand of timing chain components/kits other than OE Ford (Motorcraft). Some here have used Cloyes kits but I'd stay away from any inexpensive Chinese kits as I've read too many horror stories about problems encountered when these kits have been used.

Personally, if you hadn't already spent considerable money on this vehicle I would advise you not to put any more money into it. With dents, rust, not so great interior, rough idle, a miss, a questionable transmission and timing chain rattle it isn't worth much, maybe $1000 where I live, assuming you could even find a buyer at that price.

Try cranking it w/out starting the engine for 5-8 seconds and see if it starts quietly. If so, just drive it until the wheels fall off.

 

[4.0SOHCTX]

The front timing chain components can be replaced with the engine still in the truck. So if that's where you noise is you might start there. The hydraulic tensioners can be replaced fairly easily, but will more than likely not offer any improvement.

I wouldn't buy any other brand of timing chain components/kits other than OE Ford (Motorcraft). Some here have used Cloyes kits but I'd stay away from any inexpensive Chinese kits as I've read too many horror stories about problems encountered when these kits have been used.

Personally, if you hadn't already spent considerable money on this vehicle I would advise you not to put any more money into it. With dents, rust, not so great interior, rough idle, a miss, a questionable transmission and timing chain rattle it isn't worth much, maybe $1000 where I live, assuming you could even find a buyer at that price.

Try cranking it w/out starting the engine for 5-8 seconds and see if it starts quietly. If so, just drive it until the wheels fall off.

It will crank quietly after the first start of the day, I'm gonna try that pre-oil technique in order to take it easy on the cold starts from now on too.

Would you say $800 for the timing job, cloyes parts+labor, is worth it now with the work I've already put into it?

Honestly, with the cosmetic damage, I wouldn't even expect to sell for 1k. I don't mind the cosmetics as long as she runs good, how much of a difference do you think new timing components can make in terms of drivability and reliability? could that fix my miss and rough idle?

 

[koda2000]

It will crank quietly after the first start of the day, I'm gonna try that pre-oil technique in order to take it easy on the cold starts from now on too.

Would you say $800 for the timing job, cloyes parts+labor, is worth it now with the work I've already put into it?

Honestly, with the cosmetic damage, I wouldn't even expect to sell for 1k. I don't mind the cosmetics as long as she runs good, how much of a difference do you think new timing components can make in terms of drivability and reliability? could that fix my miss and rough idle?

I sometimes get a miss on #4, but only right after starting. It's pretty rare for it to happen. When it does it will set the CEL (which I then reset). IDK that it has anything to do with the timing chains and it's always the #4 cylinder.

I have the Job 2 engine which has much better intake O-rings, but I've replaced them with no improvement. Have you replaced your intake manifold O-rings? They are a common cause of rough idle and miss especially with the Job 1 engine upon a cold start in colder weather. The O-rings get brittle and shrink, allowing air leaks. As the engine warms, parts expand and can stop/reduce the un-monitored air from leaking in. You should also do a compression test to make sure you don't have any cylinder leaks.

Is it worth putting another $800 into it? That's up to you. In for a penny, in for a pound. As I said, I wouldn't do it.

 

[4.0SOHCTX]

I sometimes get a miss on #4, but only right after starting. It's pretty rare for it to happen. When it does it will set the CEL (which I then reset). IDK that it has anything to do with the timing chains and it's always the #4 cylinder.

I have the Job 2 engine which has much better intake O-rings, but I've replaced them with no improvement. Have you replaced your intake manifold O-rings? They are a common cause of rough idle and miss especially with the Job 1 engine upon a cold start in colder weather. The O-rings get brittle and shrink, allowing air leaks. As the engine warms, parts expand and can stop/reduce the un-monitored air from leaking in. You should also do a compression test to make sure you don't have any cylinder leaks.

Is it worth putting another $800 into it? That's up to you. In for a penny, in for a pound. As I said, I wouldn't do it.

I do believe I replaced all the O rings when I did the intake manifold gasket because they came together. left that off the list.
maybe a compression test might be more useful than just replacing the timing. I know that since its a non-interference engine the failure of a timing component isn't catastrophic.
Might as well just run it into the ground slowly and start saving for the next truck.

 

[koda2000]

I do believe I replaced all the O rings when I did the intake manifold gasket because they came together. left that off the list.
maybe a compression test might be more useful than just replacing the timing. I know that since its a non-interference engine the failure of a timing component isn't catastrophic.
Might as well just run it into the ground slowly and start saving for the next truck.

Oh, no no no! It is an interference engine and a timing chain failure will absolutely be catastrophic.

 

[swshawaii]

FALSE

I know that since its a non-interference engine the failure of a timing component isn't catastrophic.

TRUE

Oh, no no no! It is an interference engine and a timing chain failure will absolutely be catastrophic.

--------------------------------------------------------------------------------------------------------------------------------------------------------------------------
FALSE

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

^ Good article other than this glaring mistake. I believe this is where the misinformation is coming from. Article was linked in the MyST forum years ago, and the "not an interference engine" statement came up. Messaged them back then, and it STILL hasn't been corrected.

Ford 4.0L V6 Engine - Explorer, SOHC, Timing Chain

 

[koda2000]

Trust me, if you break or jump a timing chain your pistons will hit the valves. This is typical death of a 4.0L SOHC engine.

 

[swshawaii]

Agree Phil, Plenty of Ford (Found-On-Road-Dead) 4.0L SOHC's everywhere to prove it.

 

[4.0SOHCTX]

Oh, no no no! It is an interference engine and a timing chain failure will absolutely be catastrophic.

Oh damn lol, I read that somewhere, glad to be corrected. if thats the case i might replace the timing in order to avoid being in a time bomb.

 

[Tech By Trade]

Theres a pretty good chance it will give you notice before the chains go. The guides shattered on mine, and the chains were running on the tensioners while we were out deer hunting. It sounded like a diesel in the parking lot at the bar idling away. I drove it home another 50 miles like that without the chains snapping. on a side note, at RPM the traction side of the chain creates tension and the engine didn't even rattle the whole way home until the RPM dropped rolling into the garage.

 

[koda2000]

My first experience with the 4.0L SOHC engine was our 2001 XLT. Like Tech By Trade's, it rattled like a diesel at start-up and idle. It also rattled at around 2700 RPM. It went about 40K before it finally jumped time and we junked it. Another problem is that, as the guides disintegrate, broken pieces of curved tan plastic fall into the oil pan and surround the oil pickup. When oil pressure drops below 5 PSI the oil pressure gauge will start going nuts and can even get the needle stuck under the low pressure peg.

As your rattle is currently only at cold-start, you should have quite a ways to go before you reach the rattle at idle stage. As long as you get some oil pressure up before cold starting, you may have many miles left before it grenades. It's not the noise that does the damage, it's the loose chains.

My '01 Sport Trac didn't rattle at all when I first got it, then started rattling from the front chain at cold-start unless I pre-oiled it. I replaced the front tensioner, which didn't help. I dropped my lower oil pan, looking broken pieces of guide, and found it to be clean (aside from a lot of sludge and a sandy grit, which is an indication of the timing chains sawing their way through the engine). About 10K later I had a slight rattle at idle and dropped the oil pan a second time to find a small piece of spring steel, which I believe is from a broken jack-shaft guide/tensioner. I just use this truck around town and plan to run it into the ground before deciding what to do with it. I bought this truck cheap, but I've put a lot of time and effort into it to get it road worthy again (at least a full page worth of parts/repairs, single spaced). If I put any more money into it at this point I'll be upside-down. I'll have had it for 3 years this May, so good enough for now.