Fluid losses going away by themselves!

Am I blessed, or what? Generally car problems get worse. I have things that fix themselves. Even my muffler with the hole in it seems to be quieter than 6 months ago. Although I might be imagining that.

But regarding my brake fluid: This winter, I'd have to periodically add some. I'd find it down a good 1/4 inch, every so often. This morning, I checked, after not checking for a good while and it is right up to the top. Do you suppose during the below 0 winter, that fluid leaked out of cylinders then, and now that it is warmer, it stopped?

Now for the good part; the engine coolant. For many months - actually about 1 whole year now, I have found that after about 150 miles, I'd have to add a quart of coolant. I have an asphalt drive, and also park on concrete. Never have I ever seen one drop on the ground, nor smelled any coolant smell in the car, nor from walking around the outside of the car! The coolant loss had been pretty steady at that rate, like clockwork - for months and months.

At first I thought it was surely a blowing head gasket. The engine temp had a history of climbing higher than normal, also. However, I never would smell that cooking engine smell, nor smell coolant, so I figured maybe a two-fold problem where one was the INTERNAL coolant loss and the other was sending unit or gauge related, or somehow related to the amount of (lack thereof?) coolant going past the sending unit.

I emphasized INTERNAL because my cylinder #3 was being steam-cleaned to the point that every couple weeks there for a while, a missfire would occur, and I'd find the insulator of the plug on that cylinder cracked inside.

Now, I haven't had to replace that plug in like 3? months, and now I am steadily noticing where I do not have to add near the coolant. On my last check I had only to add 1/2 qt. + in 750 miles!

So something must be plugging itself shut?

But have you ever heard of a cracked block?, or cracked head?, or hole in a head gasket doing this? Hardly?

So what about the intake manifold? On an early 90's Dodge Spirit, does the coolant go through the intake manifold and a gasket there? And for some strange reason could that be what is sealing itself shut? Any of you garage mechanics have experience in dealing with such a thing?

I have not added any stop leak procucts for over a year, and last May I replaced the radiator and lots of cololant, and never havbe added stop leak since - for absolutely sure - so I'd think most of the stop leak, that WAS in there, would be gone, or greatly diluted. Besides, the coolant losses became worse and worse during the year of 2007, and during the cold winter of 2008 is when I was getting missfires and steam-cleaned plug, and replacing that plug - so if there was still some stop leak in there, leftover, that would not make any sense that it did not stop it then, and now it IS stopping.

Unless I am on some lucky streak, which makes no scientific sense.

 

It's hard to tell, but hot weather outside tends to swell seals. With the seals expanded, leaks tend to go away.

 

Head gaskets dont have to "BLOW"...they CAN leak small amounts into the chamber.

RAD replacement?...any Flakes or chunks from the radiator will be just as effective as stop leak...and possibly floated around and fixed your leak.....But no promises over the long haul....

 

Now THAT is an interesting theory! Since I have never flushed my cooling system. (Yes - I'm the same one who has never changed the oil, either. ) And perhaps in the case of gasket failures, this may be a blessing in disguise? And maybe it will last if flakes (if that is what it is) are the right stuff, because stop leak additives are often just organic I found out.

Don't bad head gaskets with a pathway for water to channel through usually end up blowing though? I have never heard of my situation before that not only has drug on with the steady loss, but now actually has improved. A year without it totally letting go? Isn't that amazing for a head gasket to behave like that? That is why I wondered about the intake gasket instead.

...............

Hot,

Well, the weather is far from hot here, but at least it is not 20 below any more. 40-50's usually now. Some 60's days.Today is to be 70 for 2nd time this year. But so far today at almost noon now my computer only says about 50. Wonder if it will make it. They updated about 45 minutes ago at 48. I think I'll take a break here and go out and feel.

 

Basically the same principal.....The operating pressure is the same in both locations. The only problem I would have with the intake theory, is an intake leak should line up with Cyl #4 , as this is where the head port, manifold, and heater hoses meet. This would be more likely of an internally cracked Intake manifold , instead of a gasket leak.

#3 is interesting , because the PVC Vacuum nipple lands in front of #3 on the intake, and I'm yet to see a 15 + year old Dodge that doesnt have degraded vac hoses. The plug may not have been "Steam Cleaned", but rather leaned out to the point of detonation, which could explain the cracked insulator.

 

Fascinating. Now you REALLY have me second guessing. I could swear that I also saw coolant down in that cylinder when I changed it. I keep a diligent journal, and now may have to go back in the journal to see if I wrote what I saw the first time I changed the broken plug. The plug insulator was as clean as a new plug. Not a white coating either. It was like new china.

So the intake gasket has the same pressure?; same as compression stroke? Never thought of that before. For some reason I thought the compression stoke was the one that really had the pressure, since both valves are closed while piston moves, as opposed to intake or exhaust gaskets that have a valve open allowing gases in or out at the time. And also from the fact I never heard of concerns about torquing the intake or exhaust manifolds with the extreme care and torque-wrench procedure as with head bolts.

 

Under normal circumstances, coolant pressure and compression should be isolated.

To a degree , you are correct. However, during a head gasket failure, the COMPRESSION far exceeds Coolant pressure. The Compression pressure leaks into the Coolant passages, Not the other way around. When you shut down the motor and compression pressure ceases, that is when the Pressurized coolant leaks into the chamber.

With the car cold.....Remove the rad cap. Start the car and allow it to reach normal operating temp. Now look into the radiator. If the head gasket is leaking , you will likely see bubbles in the coolant.

At the shop.. We sometimes use an emmissions analyzer to check for exhaust gas at the Radiator neck, on suspected head gasket failures.

 

In MY radiator, it takes a bend about 1 inch down. I have seen tiny bubbles in reservoir though, at times, but not at others. One has to be absolutely certain when going by that, that it not a teeny cap leak, though.

I follow that about the gaskets. Yes, upon compression gases are forced into the water, not the other way around. I knew that. The coolant would be drawn back into the cylinder at shutdown/cool-down vacuum.

So what I was trying to figure out is WHERE it is being sucked in at, for certain.

I appreciate your diligence.

 

occasionaly you can have a gasket failure on a thermal vac switch where the engine can suck coolant around the o-ring seal in the switch, this will cause loss of coolant without puddles. The switch might quit if you start pulling less vac, or with contamination but eventually it will leak again. If you look in a quality shop manual it will give a torque spec and sequence for both intake and exhaust manifolds. Also I have seen leaks that were small enough that all of the coolant evaporated and did not drip. But yours does not sound like it would be that slow. regarding the brake fluid the use was probably going into the front calipers. Disc brakes use more fluid to opperate than drum brakes and so can show more fluid drop. check your front pads, check for sticking caliper pistons. Brake fluid doesn't just evaporate or disapear. If you are having to add you need to get that system checked. No brakes is very bad!!
Life begins when the kids leave home and the dog dies

 

I have a 90 f-150 straight six that seems to be doing the samething with #3 cylinder, and I noted the same thing with the plug. About 2 years ago it was loosing coolant and I narrowed it down to a bad rad. cap and that was fixed, now it is loosing a little coolant periodically but no miss since I changed the plug, maybe I will try the silver powder, I know it is not permanent but hey, It's a 1990 who cares, I will run it till it blows! and get another one.

 

Tell me more about this switch. Does mine even have one? If so, where is it? What does it do?

 

I can't remember if your veh has one but it is easy to check, follow vac lines to the engine and see if they run into something that has 2 or more vac lines and screws into the engine or intake. If it is brass at the bottom it is a thermal vac switch. They have wax with a set melt point in them to open at a certain temp depending on what the engineer was trying to activate. some cars had 2 or 3 on them. But with out looking at a vac diagram I would not know how many or what style you have.
Remember Murphy was an optimist.