Thats All She Wrote

[Lazzman]

Thats it for my 1998 Explorer Sport :roll:.

Engine is Fried due to Timing chain tensioner issue and I was about 600mi short of 200k mi.

I went to change out the spark plugs yesterday and the left side cylinder bank came out no problem and they all looked to be in excellent condition with no fouling or oil build up. The right side however were in bad shape, covered with oil and fouling marks.

The right front spark plug closest to the timing chain tensioner was loose in its hole and when I pulled it out the top electrode was sheared clean off and the threads were stripped on one side. Dark black fouling all over the ceramic and some oil. Well I was puzzled but still replaced the plug, I new it was not going to be good when the plug would not tighten down but just kept spinning.

When I went to start the truck I heard serious knocking coming from that Piston and then a lower end rap and compression was way down. Truck could not hold idle either. I did not drive it on the street just moved it around my driveway a bit.

About two years back I found pieces of the plastic timing chain tensioner in my oil pan and new what was up, but the truck still ran great. Funny thing as it also did about 10 minutes before I changed out the plugs.

Still don't know what really happened but I can tell you that the piston and valves must be really damaged in that cylinder.

My Thanks to the site for all of the great advice I was given over the years A used or rebuilt engine would cost $$$$ way more than I want to invest in this truck and would rather put that towards a down payment on a new Explorer.

Without the help of this site and its members my X would have been ready for the Bone yard many years back and heck with a rebuilt engine it would still be kickin ass.

Still kind of stunned as I am without transportation and my good friend for the past 12 years.

 

[MrQ]

Dang that sucks. Is that 200k on an original SOHC without a timing chain fix?

Good luck in search for a new Ex. What gen you looking at?

 

[celly]

Sorry to hear Lazz. I hope you re-join the Explorer ownership ranks again soon.

 

[Glen4X4]

Sorry to hear of your misfortune with your truck but you've accomplished quite a few miles with your explorer. Maybe we will see ya around here again.

 

[2000StreetRod]

What a shame!

Thats it for my 1998 Explorer Sport :roll:.
. . . The right front spark plug closest to the timing chain tensioner was loose in its hole and when I pulled it out the top electrode was sheared clean off and the threads were stripped on one side. . . . When I went to start the truck I heard serious knocking coming from that Piston and then a lower end rap and compression was way down. . . . Still don't know what really happened but I can tell you that the piston and valves must be really damaged in that cylinder. . .

The right front spark plug (#1) is farthest from the right bank tensioner near the firewall. Were you referring to the left front tensioner?

My first thought is that the right bank timing chain slipped enough for the piston to collide with one of the valves enough to bend over to strike the spark plug. The spark plugs are angled toward the exhaust valves as shown in the photo below by shelbygt.

However, if that happened I supsect there would be zero compression for that cylinder. Are you sure there aren't just spark plug fragments laying on top of the piston?

 

[hotkarl]

Just throw a junkyard motor in it. Cheaper than buying a new car, and at least you know "your" vehicle as opposed to buying another used vehicle with god only knows what's been done to it, or how it's been treated.
I came pretty close to ditchin' my Explorer on a few occassions, but screw it, I know this baby inside and out and the thought of buying something else for a few grand and having something major go wrong just isn't worth the gamble, and a monthly payment is totally out of the question. My vote is to get her running again.

 

[97xlt4.0]

I vote to get her running again too....I'm not far behind you mileage-wise, and that's what I'm doing when the time comes!

 

[hotkarl]

I'd love to know how I can find out if my ex took advantage of the death rattle recall.
Got stickers all over the damn thing for various recall replacement parts/repairs.
I'm at 135K with no death rattle, so I'm wondering if maybe it was addressed already. I'm ready, willing, and able to go to 200k, actually looking foward to it. Bring it!

200k is a milestone. You don't put down an ex if it's gone that far. You wipe off your shirt and keep going...
If ya shop around you can get her up and running for in or around a grand with a used engine. I think that's far less a gamble than buying something else unless you have the financial means to go new. Ya know the old saying about the "devil you know"...

 

[Lazzman]

Thanks for all of the sympathy & helpful comments, very much appreciated, that is why I love this site so much- great board members

I went out again tonight and started it up, not a bad rattle it does sound like some spark plug fragments are rattling around in the cylinder. The other problem is that the spark plug threads on the engine block for that cylinder are stripped out by the Piston valve collision- so the plug is in there only loosely it would not get tight. I am definately loosing compression in that piston.

It is the piston that is on the drivers side to the front of the engine directly behind the EGR Valve. Seems to be near where the part for the 00M12 tensioner goes.

I had the 00M12 done back in 2002.

The engine is so strong and in such good shape, as is the interior. I have decided to take it to my mechanic and let him have a go over it, as the knocking is intermittent & not that bad. It could be just a bent valve or the piece of the spark plug that broke off. Though loosing compression in that cylinder through the spark plug hole is not helping matters.

I have attached a pick for reference, plugs are lined up exactly how they came out of the engine if you're facing the engine bay with the drivers side on your right.

 

[2000StreetRod]

aluminum foil

While attending college I owned a 1958 Jaguar XK-150 with inline 6 cylinder DOHC engine with magnesium alloy head. The previous owner had overtightened one spark plug and partially stripped the threads in the head. The spark plug would blow out and hit the bonnet when the engine revved above 3500 rpm. Until I could afford to pull the head and insert a heli-coil I just inserted a strip of aluminum foil in the hole before inserting the plug. Then the plug would hold until about 4500 rpm. Now I would not even consider doing such an irresponsible act.

I suggest that you get a worst case estimate from your mechanic before authorizing repair. You could end of paying for rebuilding the head, replacing the left timing chain cassette, and replacing the primary tensioner and guide which requires pulling the front timing cover. Make sure your mechanic has the SOHC V6 timing tool set and has successfully timed an engine with the set before.

 

[Rudy602]

It always sucks when "stuff happens" but don't let it be a deal breaker, at least do an autopsy and find out for sure what's up - you might be surprised. If it's time to upgrade and you can swing it, good for you - If you have something else to drive and have the time, you could fix your's for cheap money compared to buying something new. The stealerships are still acting like the economy is doing fine and a car is worth as much as a house. Good luck with whatever you decide.

 

[Paraphoe]

Wishing you luck, Lazz. Don't want to see another good truck go to the heap.

 

[eoliva]

Man I hope mine makes it atleast 200k I would be happy considering what I bought it for. With that said could this have been avoided by having the tensioners replaced before mishap occurs? I have read all about the timing chain problems (or more like tensioner problems rather). I currently have 134k on my 98 XLT. Are there any precautions we can take to prevent this from happening - obviously replacing he tensioners / chain - but what about inspecting for damage early on?

 

[GRNMACHINE]

Wishing you luck, Lazz. Don't want to see another good truck go to the heap.

x2.

Good time for a V8 swap!

 

[Lazzman]

It would be awesome to drop a V8 in there, especially with the 4.10 gears.

Thanks for all of the positive advice, will keep everyone updated.

 

[Lazzman]

Anyone know of a good engine repair shop in Massachusetts? One familiar with the timing chain set up of the 4.0 Sohc Ford Engine?

 

[Glen4X4]

Lazz if you take it to a reputable shop they should have the engine tear down manual to the engine and know the exact procedure for repairing the engine.

 

[Lazzman]

I was able to drive the truck around today for about 10mi with no real issues just a little tick in the cylinder with the bent valve. The Spark plug is very loose in the engine block on this cylinder and causing a lot of blow by.

It seems that the timing in Cylinder 4 I believe, was off and the piston collided with the valve which bent and smashed into the spark plug end. As seen in the photo it sheared off the side electrode and must have striped some of the threads on the spark plug block.

When I put the new E3 Spark plug in it did not have enough clearance, as an E3 plug has a huge Diamond fire Electrode and I believe it was this that caused the extra noise and chatter- until the valve bent enough to get around it.

The good news is the truck is still driveable and will be going to a repair shop soon.

So it was Cylinder #4 not cylinder #1, so now we know it was the left side timing tensioner that broke.

 

[Joe Dirt]

So do you think the length of the E3 plug caused this horrible mess?

 

[2000StreetRod]

Slipped timing chain?

I'm not convinced that the timing chain has slipped. If it had slipped, all of the valves on the left bank would be out of time by the same amount. A simple compression test could verify if the chain has slipped. If the compression on all of the left bank cylinders is low then the chain has probably slipped.

How many miles did you have on the bad spark plug in #4 cylinder? From the photo it almost looks like it failed from corrosion or detonation.