Car repair II... What not to do

[grislyatoms]

1. Panic
2. Rush
3. Turn off brain
4. Read the directions later

 

Every so often I get handed a big old slice of humble pie and I dig in with both hands.

Shuttle dropped me off at the parking lot yesterday afternoon. I found some antifreeze under my pickup and investigated. It looked like the bottom radiator hose had been rubbing against something and had a slight little leak. So, I top off the antifreeze and head to the bank and the auto parts store.

The line in the bank was ridiculous. I started getting wound up as I knew I only had a little bit of daylight left and didn't want to replace the hose in the dark. Finally finished my business and headed to the parts store.

Uh-Oh. Temp gauge rising quickly. Of course I was boxed in and there were no side roads. I just cut the engine and coasted to a point I could turn off the main road. Pop the hood and take a look. Oh (*&^^%(, the antifreeze looked like it was coming from the water pump and then running down the bottom hose. Checked the play in the pump, it was wobbling a bit. So anyway I limped it over to the auto parts store and bought a new hose, couple gallons of antifreeze, thermostat, clamps, water pump, gaskets, and monkey snot.

Get home, and just as I'm pulling into the parking space, the charge light comes on. (I'm hoping the belt just got slick from the antifreeze and slipped a little, and that the alternator did not drown in antifreeze.)

It's twilight by this time. I took my jump box and attached the little gooseneck lamp that came with it and got busy. Two bolts, the thermostat housing was off. (Here's where I turned off brain. Were brain not addled with "Hurry the hell up" I might have thought it through)

Unbolted pulley from pump and the fan from the clutch. "How the hell do you get the fan clutch off the pump? Well, I'll get the whole works off there and into the light where I can see it, then maybe I can figure it out". (Reading the manual and engaging brain here would have been helpful)

Two top bolts off the water pump, (busted my knuckles on the fan 3-4 hundred times), finally got the other two bolts off. Water pump wouldn't come off. I noticed that there had been a slow leak from the thermostat housing that had sort of crystallized around the pump and stuck it on there really well. (Second chance to turn brain on)

Got a 2x4, put it on top of the water pump and started whacking. No dice. Fiddle-fool around, no dice. Whack some more, nothing. Look at new water pump. Replace ambiguous bolt and remove last water pump bolt.

One whack with the 2x4 and the pump came off. "Piece of cake, I got this nailed!"

Spent the next 45 minutes trying to figure out how the clutch comes off. Then I notice the huge nut on the fan clutch. Uh-oh. It's marked "Tighten" with an arrow marking the direction. Feeling of impending doom. Consult manual.

Need a breaker bar, a special crow's foot, and a special wrench to get the fan clutch off. I cursed blue fire for 5-10 minutes and damned Ford engineers to a special place in hell I reserve for Brussels Sprouts and squash.

"Well, I can't do diddly about it tonight".

It was then that I noticed that the water pump had no play in it, it was the fan clutch. Ran back outside. "Well, maybe it...was...actually...leaking...from...the...thermostat...housing... I didn't actually see it leaking from the weep hole. (Another example of not thoroughly checking stuff).

I popped the thermostat out and plopped it in a pan of boiling water. Nothing. 20 minutes of cursing blue fire. At that point, I was too cold to do anymore work, though.

It was the friggin' thermostat the whole time. It was only then that I remembered I had checked the top hose when I had to pull over when it was about to overheat, and it was cold. Classic "thermostat stuck closed" scenario.

Anyway, I walked down to the bus stop this morning to ride into work. Extra early. I thought "Today is not a holiday, they should be running." Wait. Wait. Wait some more. "Guess they aren't running this morning". Walked over to the phone booth to get the number for a cab company. Call for a cab, then call El Jefe to let him know I'll be a little late. Sit down on the bench to wait. Zoom! there goes the bus. Canceled the cab and walked back over to the bus stop.

Anyway, I was only 8 minutes late.

Not looking forward to putting everything back together tonight in the dark and cold.

One more little thing. The original thermostat is 192 degrees. In high altitude (I am over 5,000 feet), I know the boiling point of water is lower (That's right isn't it?). Could the water in the pan not have gotten hot enough to open the thermostat? The 180 degree replacement I bought opened right up. I find it hard to believe that 12 degrees would make a difference, but, as is obvious from my post, what do I know?

[grislyatoms]

Just had another thought.

How advisable would it be to just purchase a new pulley and fan and just forego the fan clutch? Would that work? I can't think why it wouldn't, and it's one less point of failure. Anyone ever try that?

[Declaration Day]

From partstrain.com:

"A cars engine needs to operate in the most efficient temperature to ensure its long life and good working condition. To do this, the excess heat should be removed from the engine to get the engine up to the correct temperature as soon as possible after starting. This whole process is being taken cared of by the cooling system, enabling the engine to perform at the most efficient temperature no matter what the operating conditions are.

Further, the radiator also needs a fan which would provide enough air to help the engine cool off. This fan has several blades, normally made of plastic, and is mounted between the radiator and the engine for the purpose of letting outside air to enter into the radiator easily. Some vehicles are equipped with additional fan placed right in front of the radiator for faster cooling of the engine because since the vehicles move slowly during hot season, only limited amount of cool air are attracted into the radiator resulting to the engines poor cooling.

To further reinforce the radiator fan, a fan clutch is often outfitted to it. Fan clutches like the Chevrolet fan clutch is a small fluid coupling with a thermostatic device which controls a variable speed fan. Its main function is to ensure that the fan will rotate at moderate speed to keep the engine from possible overheating. It is also designed to minimize drive to the fan when the said fan is no longer used or needed.

A fan clutch has a fluid coupling partly filled with silicone oil to be used solely for that purpose. The fan clutch regulates the heat alerts a bimental coil spring to uncoil or expand for that matter in case the air temperature passing through the radiator rises because as it expands, only a little more oil is allowed to enter the fluid coupling thus triggering the fan to rotate. On the other hand, if it is a cool air that will enter the radiator, the oil instead contracts leaving the fluid coupling and the fan is slowed down, consequently reducing fuel consumption, minimizing noise and saves engine power. The fan clutch is a very important component of the cooling. Immediate   replacement of which is essential when you think that it is no longer functioning well."


Despite this rather lengthy write-up emphasizing the importance of the clutch, I believe you'll be ok without it.  Your fan won't operate as smoothly, and it may take a bit longer to reach operating temp, but on a big ol' pickup you may not even notice.  I'd just be concerned about fan blade clearance issues if you delete the clutch.

While I've never done what you're proposing, I've rigged electric fans on old beater FWD vehicles to come on with the ignition, because for one reason or another the car's computer didn't turn it on / off when needed, and the car wasn't worth paying to take it to a shop for a proper repair.  With the fan running all the time, the car took longer to heat up initially as I suspect your truck will, but there were no other adverse effects.

Good luck!

[grislyatoms]

Well, I answered one of my questions. Sort of. This from wikipedia:

"For this reason, high elevation cooking generally takes longer since boiling point is a function of atmospheric pressure. In Denver, Colorado, which is at an elevation of about one mile, water boils at approximately 95 C. [1]"http://en.wikipedia.org/wiki/Boiling

95C is 203F. 203F to activate a 192F thermostat is not much wiggle room. Anyone know what the tolerances are for automotive thermostats?

[grislyatoms]

Thanks, Declaration Day. I think I could get it to work, but I've got to weigh the pros and cons. Original equipment vs. my hillbilly engineering , cost vs. benefit, etc.

I'll look into the electric fan idea, but I think it would be too much $$$ and trouble. FWIW, I rigged up an old ('85?) Subaru Brat with a constant electric fan (as a temporary measure) when I was in high school. It worked, but like you said, it took forever to warm up.

[Tallpine]

I don't think the fan on my old GMC works like that ... it seems to work on "airspeed."

Sometimes when driving downwind at hiway speeds, the fan clutch doesn't disengage.  It sounds like you are driving a Cessna 180 down the hiway at 60 mph but you never take off.  I could have almost put the stick in neutral and sailed home

[Declaration Day]

I'll look into the electric fan idea, but I think it would be too much $$$ and trouble. FWIW, I rigged up an old ('85?) Subaru Brat with a constant electric fan (as a temporary measure) when I was in high school. It worked, but like you said, it took forever to warm up.

Just to clarify, I wasn't suggesting swapping out your fan for an electric one. 

On the cars I spoke of, I used the OEM fan that was already in place.  I simply cut the factory circuit to it and re-wired it to come on with the ignition.

[Larry Ashcraft]

I replaced the clutch fan on my 1968 Mustang GT (390) with a flex fan from a high performance shop.  It was a little more noisy, but worked fine and was trouble free.

Of course, the 400hp (after modifications) big block with Hooker Headers made plenty of noise on its own, so I didn't notice it much.

[Brad Johnson]

95C is 203F. 203F to activate a 192F thermostat is not much wiggle room. Anyone know what the tolerances are for automotive thermostats?

Remember that your system is under pressure - 10 to 16 lbs, depending on the vehicle.  192F is fine and will keep you nice and toasty way up there in the chilly grey boonies.

Brad

[mfree]

I was about to say, the cooling system isn't at atmospheric pressure unless something's wrong. Most caps I've seen are between 8 and 14 psi release.

[Daniel964]

WOW. Compared to my knowledge and skills at car repair you all are FREAKING GENIUSES ! ! I hope next summer to learn how to do oil changes. LOL. I'm ok at plugs and wires but thats about my limit.

[230RN]

I've locked up the fan clutch on a Datsun 240Z and the only bad effect was it took a little longer to warm up.

Up here (I'm also a mile high), the air density is lower (about 12 psi as opposed to the 14.7 psi at sea level), so it takes more air flow to cool an engine anyhow.  So locking the fan up will probably not do any harm at these higher altitudes.  (And bullets sail along a little better, too.)  The radiator on that car looked incredibly inadequate anyhow, and it used to overheat with fair regularity on hot days.

I hate fan clutches.  Gimme a thermostatically-controlled electric fan any day.

[grislyatoms]

The thermostat question was for troubleshooting purposes only.

I put the 192 degree thermostat in a pan of boiling water and it didn't open. Then I started thinking well since we are so high up maybe water doesn't boil here at 212 degrees. And I was right, it boils at 203 degrees. 203 degrees to test the opening of a 192 degree thermostat sounds a little dicey to me as a definitive test.

If the tolerance for that thermostat is +or- 12 degrees, it may very well not have opened during my stovetop test. That's what I was trying to get at.

Maybe I'll drive down to a lower altitude, fire up the camp stove with a pot of water and see if it opens there.

Anyway, I have it almost all back together. Just have to do the thermostat and housing, route the belt, replace the shroud, etc., fill it up with antifreeze, and then cross my fingers. I won't know about the alternator until I get it running again.

Sheesh, I do not want to spend another couple of nights turning into a popsicle. I believe I was between stage 1 and stage 2 hypothermia when I threw in the towel last night. No joke.  

Still considering the flex fan idea, but that will definitely wait until it's warmer out.
 

[RocketMan]

I put the 192 degree thermostat in a pan of boiling water and it didn't open. Then I started thinking well since we are so high up maybe water doesn't boil here at 212 degrees. And I was right, it boils at 203 degrees. 203 degrees to test the opening of a 192 degree thermostat sounds a little dicey to me as a definitive test.

The thermostat doesn't care if the water is boiling or not.  It responds strictly to temperature.  192 degrees is 192 degrees, regardless of the altitude.
With a plus/minus 12 degree tolerance, you might not have gotten the temperature high enough to open that particular thermostat.

[CNYCacher]

With all this talk about boiling water and altitude, are you forgetting that the top rad hose was cold when you pulled over?

Get a new thermostat.

What are they, $5?

Oh, don't nix the fan clutch either.  You would be surprised at how little the fan is used, usually just when you are idling.  At speed, the natural airflow over the radiator is enough to do the cooling, and the clutch is not engaged.  If you do away with the fan clutch and direct-drive the fan, you will see your fuel economy take a huge dive.

[Larry Ashcraft]

Flex fans flatten out at higher engine speeds, requiring less power to turn them.  They don't affect mileage much, if at all.

[grislyatoms]

Got it all back together last night.
Still a little leak from the thermostat housing, I think I may have buggered the gasket. But, considering there was already a slow leak there... Ahh, I will have to investigate further. Good excuse to go buy a pressure tester.
The water pump was pretty bad. The bearings had a lot of slop in them, I'm really glad I replaced it. 

In any event it's on the road again.

Lessons learned:

1. RTFM FIRST!
2. RTFM
3. RTFM
4. Have the proper tools as evidenced by... RTFM!
5. Relax
6. Think things through

I also learned how to read a bus schedule and found an extremely convenient route to/from work. No transfers. Get on right down at the corner, get off at work. 30 minute ride one way. I am going to use it daily, it sure would save a lot of gas, traffic stress, and wear and tear.

[Brad Johnson]

Flex fans flatten out at higher engine speeds, requiring less power to turn them.  They don't affect mileage much, if at all.

But they make that nifty jet-engine sound, though...

Brad