Engine running (too) hot

[Vitamin G]

I'll spare y'all the sob story and give it to you in a nutshell:

200 miles from home the SHO decides to nearly overheat along the highway. Recognizing the signs of an impending heat spike, I pulled to the shoulder, let it cool (45mins or so), got it to the nearest shop where I was told it was a possible head gasket failure. However, after reading a number of the existing posts I'm not so sure it is the HG.

The valve cover gaskets, radiator and water pump are less than 5k old. It had a heat issue recently that turned out to be a faulty rad. cap ... got that replaced and it ran fine until this latest incident.

There doesn't appear to be any coolant in the oil (it's nice and golden colored, proper consistency) but there is a kind of sludge in the coolant reservoir ... and some brown-ish sludge on the radiator cap (looks like, well, crap)*. The motor runs strong and idles well, there's no white smoke or excessive H20 from the exhaust. There is however a bit of carbon on the inside of the exhaust tip ... but no more than what is built up in my 5.0 Explorer's exhaust tip (and I'm pretty sure it's not having issues). There's no funny smells or leaks that I can detect.

If you have any ideas on what this might be, I'm all ears. Also, I'm thinking of driving it to the nearest shop for another opinion (probably low speeds in the cool of night). How much risk would I be taking?

* The previous owner tried to use Stop Leak instead of getting the radiator replaced or repaired. Even after I had the rad. replaced there were signs of that crap in the coolant res. Could it be coming back to haunt me?



Anyway, let me have it ... I'm hoping for the best but preparring for the worst. There's really nothing you can say that will hurt too much (unless you tell me it's hopeless )

Thanks

 

[yamahaSHO]

Stop Leak = Plugged radiator. Replace it!

 

[SHOoff89]

Stop leak is bad stuff. I would look at getting a new radiator soon, but until you find what is wrong with the car, do not drive it anywhere.

 

[Mr Anonymous]

Stop Leak = Plugged radiator. Replace it!

And have the rest of the system flushed, as well as get it pressure and leak tested.

 

[Vitamin G]

Well, by your reactions it doesn't sound like the HG ... which is very good. OTOH replacing a brand new radiator doesn't sound like much fun either.

I'm assuming the shop I took it to didn't do a complete flush/purge when they replaced the rad. in the first place ... which breaks my confidence in their attention to detail. However, I believe it's still under warranty (parts and labor), so I'll go back there an demand they do it right. Then I'll find a new mechanic.

Thanks for the info! You've eased my fears ...

 

[Whiner]

Have you changed the t-stat lately?

 

[Vitamin G]

*#$@!!!

Update: Got the car back yesterday (nearly 1 week later ) ... mechanics at the Ford dealership ran it, tested compression and leakdown and, other than the Stop Leak, couldn't find anything wrong with it. So I had the system double flushed. Drove it home last night and the needle still went to mid "N" ... it only seems to get hot under a load (idling doesn't heat it up much).

Anyway, to answer your question Chris, I haven't had the t-stat replaced yet, but I think that's where my mod money is headed

BTW any chance it could be a warped head if the HG is still okay? If so, is there any good way to tell without taking everything apart?

 

[F-22 Raptor SHO]

Couple of things:

1: Glad you double flushed it, but what does that mean? Drained it and filled with water? Or did you use a Radiator flush? I would suggest a superflush from the autoparts store. Make sure you have the heat on full blast when you flush it to make sure the heater core gets flushed too.

2: Does your fan turn on ever? If not, you might want to look at why it isnt. Verify that it works by turning on the AC. The fan should kick on right away.

If the fan doesnt cycle on, then the temp sensor on the fan shroud might be bad.

3: Replace that t stat...yourself. Its not that tough.

4: The gunk on the radiator cap was probably the stop leak. Stop leak isnt bad stuff as many of the youngins on the board might think. It serves a purpose, albeit a temporary one.

5: check the oil cap for sludge which would indicate a blown head gasket. I doubt it is blown if you arent seeing the symptoms (billowing white smoke from exhaust, unexplained massive coolant consumption, a milkshake froth on the oil cap and most of all an extremely high oil level (like quarts above the fill line).

6: Last resort: water pump might be bad (ie disintegrated. Rare, but possible).

Keep us up to date.

 

[Vitamin G]

Thanks for the ideas, Raptor! After reading through posts in this thread and a couple of others I decided I'd try the t-stat ... I'm betting the current one is the original "A" part. Anyway:

1. I'm not entirely sure what went into the double flush ... it was done at a shop. However, I do know that they made sure to purge the heater core at the same time.

2. The fan does kick on, but I haven't been paying attention as to when it does. I'll try it out this evening (if I get home before 10:30 )

3. I found the "how-to" at SHOtimes.com ... I think I'm ready to get my hands dirty BTW has anyone tried a 219 Napa t-stat? It doesn't appear to have "jiggle valves" but they're not necessary are they?

4. That was the feedback I got from both shops as well. I'm now fairly confident it wasn't anything worse *crosses fingers*

5. I haven't checked the oil cap yet ... didn't even think about it! Anyhow, I'll do that tonight as well. As for the symptoms, you're correct ... I haven't seen the white smoke, massive coolant consumption or an extremely high oil level (last time I checked it the level was right where it should be and a nice honey brown color).

6. Water pump ... yeah, I suppose it could be a defective unit. Being new doesn't automatically mean it's good Actually, it wouldn't be the first time getting a bad part from this shop. We've taken our Explorer back to them repeatedly to get the pinion seal replaced ... we're on the fourth one in 3 years! Once they're done doing the warranty repairs, I'm shopping around for another mechanic ...

Anyway, I'll look into a couple things tonight and swap out the t-stat this weekend. I'll make sure to post my findings.

Thanks!

 

[AutoSHO]

Use the Motorcraft Thermostat. The Jiggle valves are necessary to get the air bled out of the cooling system in a timely fashion, and the Motorcraft flows more than most other generic thermostats.

 

[F-22 Raptor SHO]

Ditto what chris said, stay away from non motorcraft t stats....just looking at the construction of one vs the other will show you why it costs more.

The water pump being "bad" like I said is unlikely...the worst I've seen here on the board was one that had lost parts of the impeller due to massive corrosion.

The whole radiator process of operation is pretty simple: hot water out, cooler water in. t stat to regulate, fan to supplement cooling during city driving, so there are only a few areas that could go to crap on you: radiator, tstat, elec fan (motor, sensor, blades), water pump, or the coolant (or hoses transporting said coolant.

 

[Vitamin G]

Well, I finally got a chance to install the new t-stat (returned the Napa part and got a Motorcraft stat as suggested) ... it took a while to get the metal pipe portion of the main line removed (the clamp on the hose above was jutting out just far enough to keep it from moving and it's such a tight space that it took a bit of work to make ample room).

Anyway, pulling the old t-stat revealed just how it could be the "weakest link" ... the shaft/spindle that runs through the middle of the part was broken and missing! Fortunately, the portion of the shaft that sits inside the engine was still intact. I'm assuming the shaft was removed from the system along with the old radiator and water pump ... so I'm not overly concerned about it coming back to haunt me.

We took her for a test drive to see if our problem was solved ... thus far the results are somewhat inconclusive. It was about a 10 mile round trip with speeds ranging from 25 to 65. For all but the last mile or so, the needle stayed on the "A". In that last mile speeds were down to 25-ish and it jumped up to "R" then "O" as it sat in the driveway idling for a little while. My wife started to get concerned, but I told her not to worry as that was about where it should be. Plus, we turned on the A/C and the temp dropped a little, turned on the heat and dropped further and faster (not sure if that proves anything, but it least it can cool down now. Before the new t-stat nothing but shutting the car off would cool it down).

So, I'm not certain that the entire problem is solved, but I think we're a good deal closer now! Thanks for all your help, guys and gals! We'll get this 'ol beast running right sooner or later