Could be the end of the line... :(

[lobo411]

Edited: problem solved. Severe front timing cover coolant leak was resolved w/ K-Seal.

Temp gauge was showing erratic overheating and the problem proved to be a failed, 2 year old Motorcraft radiator cap w/ only 4000 miles on it. Can't trust nothin' these days!

--


1996 Explorer 4.0 OHV 172k. Salvage title. Some drunk chick plowed into the rear while it was parked on the street one night, and pushed it 30 feet up the street and into two more cars. The cops were amazed. Her car was destroyed. Mine just needed to have the bumper attachment points on the frame straightened, which I accomplished with a sledgehammer and a makeshift anvil. Love that about these Explorers!

Pretty clean body for a 22 y/o truck, clean interior except for the usual driver's side seat leather wear, lots of recently replaced parts in the last 2 years (fan, fan clutch, a/c low pressure valve, blend door, both driver and passenger tail window seals, new headlamp and turn signal plastic housings, radiator overflow tank, high-mount third tail light converted to LED, new battery, new water pump, etc...).

Recently passed smog with flying colors.

But recently...electrical issues: overhead console and radio displays blank out randomly when headlights are on, instrument cluster gauges occasionally read incorrectly.

A/c issues: the a/c cools fine, but I occasionally hear a growl when the a/c kicks in and I have the hood up to hear it

Code issues: Cat below efficiency code, which can usually be ignored, but also a gross evap leak code that I can't track down. I also replaced the fuel cap, but no joy.

The front end needs to be rebuilt--the rubber grommets went a long time ago, and I'm getting noises from the front end when I go over a dip or a speed bump.

All of this is annoying, but for now, can be ignored.

And then today...the kicker...the front timing cover gasket is leaking pretty badly from the driver's side only...probably about a drop every 5-10 seconds. I replaced the front timing cover gasket about 4 years ago and have only put on about 10000 miles, so this is very premature and very unwelcome. I tried torquing the timing cover bolts above the offending water jacket, and they did snug down about 1/2 turn, but the leak is still present. The oil looks fine, and the passenger side is dry as a bone.

I guess I'm at the second to the last stop...I'm going to put in some stop-leak and hope that buys me a few months or years, and do no further repairs on anything. Kinda sad about it...it's been a great vehicle and I really love having the ability to move cargo easily without having to have a pickup, but...I know what my Dad would say if he were still around. "It's nickel and diming you...dump it!"

It's not about the money...I'm going to lease a new electric car as soon as I find a good deal. I just thought I could keep the Explorer running more or less forever, but as I was out there just now...blazing hot sun roasting my back, blazing hot engine scalding my front, I realized...I'm done.

 

[lobo411]

@koda2000 What's the name of that stop leak you're always recommending?

 

[koda2000]

@koda2000 What's the name of that stop leak you're always recommending?

K-Seal. I'm betting it will work for your leak. It's worked for me on a leak just like yours and even on a leak that was much worse.

Shake the bottle really well and add it directly to the radiator, then let the engine idle for 30 mins. My leaks stopped in minutes and never returned. If you notice a drip after the leak stopped don't worry about it. K-Seal remains active in the cooling system and will reseal future leaks. It's probably a good ideal to leave you heater on high, but it's not really necessary. K-Seal wont plug it.

 

[lobo411]

K-Seal. I'm betting it will work for your leak. It's worked for me on a leak just like yours and even on a leak that was much worse.

Shake the bottle really well and add it directly to the radiator, then let the engine idle for 30 mins. My leaks stopped in minutes and never returned. If you notice a drip after the leak stopped don't worry about it. K-Seal remains active in the cooling system and will reseal future leaks. It's probably a good ideal to leave you heater on high, but it's not really necessary. K-Seal wont plug it.

Thanks! Just picked up a bottle at Pep Boys...giving it a shot now!

 

[lobo411]

Well, there seems to be an improvement. I installed the K-seal and let it idle for a few mins, and then I decided to drive it to Costco to get gas (I figured...idling at Costco is just as good as idling in my backyard). The leak does seem to be stopped, but there was some temp gauge cycling. Normally, my temp gauge needle hangs out right over the thermometer icon, but ever since the leak got bad, I've seen the needle swing to the upper 1/3 of "normal." We'll see, but at least I'm not leaking coolant!

 

[koda2000]

Glad the K-Seal seems to be working for you. In my experience, temperature cycling is usually due to trapped air or low coolant.

 

[lobo411]

Thanks! The seal seems to be holding...no leaks at all today!

I think the wandering gauge issue may be a separate electrical thing, and the temp may not actually be going up:

The console and the radio displays blanked out while driving home at night/headlights on a few weeks ago. I was able to make them come on and off by playing with the dash illumination dimmer, so I just worked that thing back and forth (figuring corrosion due to disuse) and the problem hasn't returned.

I noticed that sometimes my gauges will read wrong. The temp reads 1/4" higher than it normally does. The oil gauge reads 1/8" higher than normal. The charging system reads 1/4" lower than normal. The engaging the turn signals causes the above gauge needles to flicker back and forth.

And then one more weird thing: if I shut down the engine while the above gauge misbehavior is occurring...the temp gauge slowly moves down 1/4" inch AFTER the engine is off. IME, the temp gauge stops exactly where it was when the engine shuts down.

I think there's a bad ground somewhere that's causing the gauges to get too much/not enough voltage and causing them to read wrong. Wish I knew more about how to deal with electronics!

 

[koda2000]

Yeah, you've got something electrical going on. The Oil Pressure gauge isn't a gauge at all. It's controlled by a oil pressure "switch", which if ON will always show the needle in the same position and if OFF (under 5 PSI of oil pressure) shows no oil pressure.

The Temp gauge is a little more of an actual gauge, but should always read about in the center of its sweep unless the coolant temp is much too cold or much too hot.

 

[lobo411]

Well shut my mouth...wandering gauge problem semi-solved! It turns out that the engine was actually running above normal as the gauge showed. I thought it might be the thermostat, and as I was replacing that part I noticed that the radiator cap rubber seal was cupped and torn.

Just to be sure, I used the crappy old cap on the engine while I bled the air out of the cooling system. The temps were as erratic as ever, so I knew that the thermostat was not the issue...it was the cap.

Crazy...this is a Motorcraft cap made in USA with about 2 years and 4000 miles on it. I ended up replacing with a Stant cap made in Mexico, and the gauge now shows normal temperature.

There is also some kind of electrical issue with the temp gauge, because I can make the needle move as much as 1/4" by adding electrical load. But I'm not as worried about that as I am about the temp gauge getting too close to overheated.

 

[koda2000]

Well shut my mouth...wandering gauge problem semi-solved! It turns out that the engine was actually running above normal as the gauge showed. I thought it might be the thermostat, and as I was replacing that part I noticed that the radiator cap rubber seal was cupped and torn.

Just to be sure, I used the crappy old cap on the engine while I bled the air out of the cooling system. The temps were as erratic as ever, so I knew that the thermostat was not the issue...it was the cap.

Crazy...this is a Motorcraft cap made in USA with about 2 years and 4000 miles on it. I ended up replacing with a Stant cap made in Mexico, and the gauge now shows normal temperature.

There is also some kind of electrical issue with the temp gauge, because I can make the needle move as much as 1/4" by adding electrical load. But I'm not as worried about that as I am about the temp gauge getting too close to overheated.

I always put a tiny bit of Vaseline on that rubber rad cap seal/washer. Keeps it from binding when the cap is installed.

 

[lobo411]

The leak is back, and another bottle of K-Seal didn't work this time around. The leak is on the driver's side, and seems to be coming from above the rack and pinion but below the level of the exhaust manifold and air conditioning.

I'm thinking it's the freeze plug that's hidden under the power steering pump. The leak is fairly large (1 gallon in 3-4 trips), but I haven't been able to see where it's leaking from. There's coolant strewn all over the lower hoses (trans, radiator, power steering, rack and pinion), but nothing seems to be actively leaking from the timing chain cover gasket. Also, the lower intake manifold gasket and water pump gaskets seem to be sound as a drum, as does the rad.

There's a ton of white, crusty, dried crap coating the engine block from below the heads to the oil pan, which seems to be from coolant streaming backwards as I drive. I'm kinda hoping the problem is the freeze plug because then I don't have to touch the other gaskets (if they're holding...leave well enough alone). I've never done a freeze plug replacement before, though. Seems pretty straightforward, assuming there's access and the thing doesn't break up when I try to get it out, right?

 

[koda2000]

Have you checked the bypass hose that goes from the t-stat housing to the w/p? Just a thought. I had one blow out on our 2000 Mountaineer 5.0L a few years ago. It made a huge mess and it took me a little while to find the hole in it hose. I've read where replacing that hose is difficult, but I didn't have any real problem replacing it using a little dish soap as a lubricate.

As far as replacing a freeze plug, I've never personally done one, but I watched a YouTube video show of a guy replacing them on a 1949 Frazier (coldwarmotors). He drilled a hole in the center of each freeze plug large enough to stick the tip of an old screwdriver in and pried the old ones out. I've also seem them removed using a large punch/drift on one side. Then he cleaned up the edges of the hole and I think he put a little sealant around the new plug, He used brass replacements and carefully hammered them home (similar to the way you'd install an oil seal). I don't recall if he used a large socket to help knock them in.

 

[96eb96]

The leak is back, and another bottle of K-Seal didn't work this time around. The leak is on the driver's side, and seems to be coming from above the rack and pinion but below the level of the exhaust manifold and air conditioning.

I'm thinking it's the freeze plug that's hidden under the power steering pump. The leak is fairly large (1 gallon in 3-4 trips), but I haven't been able to see where it's leaking from. There's coolant strewn all over the lower hoses (trans, radiator, power steering, rack and pinion), but nothing seems to be actively leaking from the timing chain cover gasket. Also, the lower intake manifold gasket and water pump gaskets seem to be sound as a drum, as does the rad.

There's a ton of white, crusty, dried crap coating the engine block from below the heads to the oil pan, which seems to be from coolant streaming backwards as I drive. I'm kinda hoping the problem is the freeze plug because then I don't have to touch the other gaskets (if they're holding...leave well enough alone). I've never done a freeze plug replacement before, though. Seems pretty straightforward, assuming there's access and the thing doesn't break up when I try to get it out, right?

To get it out you just strike it. My passenger side rear was leaking.

I ended up using a copper screw in one. I couldn't get a good enough angle to get a real one in, and I had a special kit too. The copper one has internal shells and a nut you tighten down. Holding for years now. There is a rust ridge around it too so it ain't going nowhere anymore.

 

[lobo411]

Well shoot...I jacked the car up to watch the freeze plugs thru the wheel well, turned the car on, and...a jet of coolant about as thick as a pencil shot out from the timing chain cover gasket. Sigh...would have to happen during the most ridiculously wet winter we've had here in a generation (storm after storm after storm).

I'm pretty disappointed in this Fel-Pro gasket too...I replaced the timing chain cover gasket about 6 years ago, but it only has 15,000 miles on it. Pretty weak.

Thanks for the advice!

 

[lobo411]

Finished with the job...definitely was the gasket. The Fel-Pro gasket I pulled out had 15,000 miles on it, and it looked a lot worse than the original Motorcraft gasket I removed at 150,000 miles. I replaced with Motorcraft this time, but I had to drive 20 miles to get it. Parts are getting scarce!

And I tore out the threads on one of the oil pan to timing cover bolt holes. My Genuine Craftsman Tough inch-pounds torque wrench crapped out mid-job and stopped clicking, so I way overtorqued it. The bolts go through the lower lip of the pan, they screw into the lower lip of the timing cover, and then they stick out about 1/8", with lots more room besides.

I'm thinking...maybe I'll just try putting a nut and bolt on the bolt-hole with the pulled out threads. For now, though, I'm using the Religious Method: just pray it don't leak!

 

[koda2000]

Sounds like fun. Ever use Heli-Coils? Great for replacing stripped out threads, but I don't see why a bolt and nut wouldn't work.

 

[lobo411]

Sounds like fun. Ever use Heli-Coils? Great for replacing stripped out threads, but I don't see why a bolt and nut wouldn't work.

So far so good...it's not leaking, and I hope it stays that way! I've heard of heli-coils but never had to use them....and I hope it stays that way!

 

[koda2000]

So far so good...it's not leaking, and I hope it stays that way! I've heard of heli-coils but never had to use them....and I hope it stays that way!

Heli-coils are relatively easy to install and can save you a lot of time and money. I used to work on all-aluminum motorcycle engines and heli-coils were a life saver when ham-fisted owners attempted their own maintenance and over-tightened/stripped engine case bolts. The heli-coil repair is stronger than the original aluminum threads.