Head Gasket leak

[flyeri]

I have a 4cyl that has developed a very small slow coolant leak. It is on the front of the engine between the 2nd and 3rd cylinder. You cannot actually see it leak but rather the evidence that coolant has run down the side of the block and a small puddle on a flat are beside the oil filter. A mechanic I have known for years suggested that I try a can of stop leak since there is not leak between coolant and oil journals or into the cylinders and since it is such a small leak. Here is the question. I have looked and I see several products. Some require flushing prior to using the product and some that don't. I have never used these products before and I do not want to cause other problems. I don't have any issue with pulling the head and taking it to a machine shop and doing a complete rework. It is my daughter's car and I plan on replacing it about the first of the year anyway. Any suggestions or experinece with "fix in a can" would be appreciated.

[Fortified Souls]

Go ahead and do it the right way the parts aren't that expensive it's about 175 for the head-gasket set at autozone. While your at it replace some seals that are normally hard to get to and do the timing belt. Machine shop work cost will depend on where you live but if i remember I got my head rebuilt for about 325 or so.

[GRANDE,GRANDE!!]

I had basically the same issue as you, and solved it the way your looking into.

I had a minute leak of coolant leaking from the jacket into the Cylinder #6.

Tiny tiny leak, which would leak into the cylinder and cause rough start ups for the first few seconds then would go away (because coolant was leaking into the cylinder right on the spark plug, causing somewhat of an electrical fault)

Anyway, i didnt want to fork out 3 grand for a HG job, so i bought a bottle of Chemi-Weld. It's the Australian equivalent to Blue Devil, a stop leak product in the USA.

If you want to know my outcome, i will tell you all now. As soon as i poured it in, nothing happen. The next day, the rough start ups caused by the coolant leaking into the cylinder onto the spark plug virtually stopped. Not even the slightest shake. So in effect, that plugged the leak.

But here is the catch, there has to be a catch afterall, who would sell you a product worth 10 dollars to fix a 3 thousand dollar problem?

Anyway, the way those stop leak products work, is once its poured into the cooling system, basically all that goopy substance sticks to the entire inside of the cooling system and creates somewhat of a 'coat' in the cooling system.

I'm talking Radiator, Heater core, and engine block. Where ever coolant flows, thats where you will have a coat of that goopy stuff stuck to the coolant paths - thats effectively how it seals the leak, after all, how would a small bottle of goop know where a leak is in the cooling system, travel there and seal JUST THAT and not stick to anything else.

This might not bother you, but it botheres me and i'll tell you why. When you add the bottle of stop leak and create an extra coat in the entire cooling system, the engine isnt able to cool as properly as it could prior to adding that stuff in there. The Cooling system becomes harder to dissapate the heat caused by the engine which will lead to overheating.

I didnt know how these things worked at the time and I was in a rough spot financially and needed to get to work and back so thats why i reverted to this, but if i had know how badly it 'screws' your cooling system i would have walked 10 k's to work and back, honestly.

What happend in my case was, about a few days after i had poured it in and stopped the leak, my radiator's cooling fan began powering on more often then in the past. I just thought it was because i had mixed the chemiweld with water - as it tells you to do, and that the plain water wasnt cooling my car as it should have. After flushing the water and replacing with coolant, the problem persisted. My cooling fan would power on 25 degree celcius days and thats with the AC off! If i turn the AC on, the car's temp guage will begin to climb slowly... Would never reach the RED zone, but then again, we never got extreme hot weather, i think the next summer we get here, it will overheat.

We're in winter now, so my car's been fine, but even if i take it out on the freeway and travel at high RPM's, my fans will kick on. Generaly, if a car has overheating issues, a highway drive will help cool the car as it's getting a lot of air, but in the case of adding stop leaks, its the other way around because as soon as you create an extra coating in the system, the higher and harder you push your car, the more heat is generated, but not dissapated because of the extra coat.

What can you do at this stage? The answer is - nothing. You cant clean that stuff out, not even with a fire hose. It's basically a part of the cooling system now it gets so baked on. You CAN however, fork money out for a new thermostat, new water pump, new radiator and heatercore which will cost you over a thousand dollars at minimum, but even if you do that, what about the engine block and water jackets? you can NEVER get that stuff out of there, so theres a chance that the car will still overheat if you change all that stuff anyway.

So my final thought on this is you can go one of two ways:

1: Dont get a head gasket job and buy a stop leak which will stop the leak the next day (ONLY IF ITS A VERY TINY LEAK!) and wrack your brain later trying to solve overheating issues, that quite simply - you cannot fix.

OR

2: Get the gasket repaired properly now and dont waste your time trying to solve overheating issues when you pour that goop in there because by that time, its already too late.

Good luck!

[carsrus]

If its a small leak and you wanna get it to last a couple more months just fill up the overflow with water or coolant every few days. Alot cheaper then doing anything else and wont hurt anything like the previous post states.

If its warm year round you can just fill it up with straight water. You can go over the full line, it wont really hurt anything. You can also pull the thermostat if its warm in your area to prevent if from overheating.

If you wanna keep the car, might as well pull the head.