I have a 95 4runner with 180k miles and I'm slowly losing coolant and I can't figure out where the hell it's going. I have a relatively new radiator and the hoses all appear to be fine. No coolant in the oil so I ruled out head gasket. It usually takes a couple of weeks for it to go about 1/2 gallon low. Once in a blue moon I'll see some drops on the driveway but typically nothing evers shows on the ground or engine. I can smell the coolant when I get out but no visual. Any suggestions??? I was thinking about having it pressure testes.

Pressure what? <img src="/forums/images/graemlins/lol.gif" alt="" /> Sounds like it would hurt! <img src="/forums/images/graemlins/zombie.gif" alt="" />

The leak could be burning up before it gets to the ground.

One easy way to find the leak is by adding a UV dye to the coolant and using the proper light to detect the leak. Here's a kit....comes in handy for finding a variety of other leaks too.


http://www.sjdiscounttools.com/mas53351.html

could be going into the cylinder and comming out the exhaust pipe as steam.

Yes yes, bummer.. I recently bought a 95 4runner and had the pressure test done by a dealer and they said perfecto. Next week after buying it I noticed that coolant fragrance and began seeking it out. I found a small drip from the head gasket. Also I found out toyota had a recall on 90-early 95 runners and trucks for bad gaskets. Unfortunately, early 95 means before 10/94 production. Even worse my runner has 96k miles and on carsurvey.org I found over 100 owners with similar milelage and the same problem!!! So I called the dealer and they said, you never know with pressure tests.... Next I call toyota corporate and they say, gee, we fixed that problem a few hundred cars before yours so woops. After much pushing and crying, they told me to pay to get it fixed and send in the info for a potential reimbursement. So you might what to do the same. I will keep this site updated on my adventure and everyone who reads this should call 1800.331.4331 or 1800.404.7636 and please give them hell!!!!!

Bummer, that if it isn't leaking on the ground, then it is probably burning out the exhaust. That is what mine did for a while before it blew out full volume <img src="/forums/images/graemlins/shiner.gif" alt="" />

Good luck fixing it,

Hugh

I had the head gasket replaced during the re-call period some 120k miles ago but I figure it must be time again. I was wondering if it's possible to leak into the cylinders. I kept looking at the oil to see if anything is getting there but nothing has appeared. I traveled approx. 300 miles today and I had to top off the radiator (roughly 1/2 gallon) about 150 miles into the trip. I noticed about a week ago that the engine was missing at idle speed so I'm figuring maybe too much water is getting to the plugs. This really sucks! All in all this has been a great vehicle and I do not run'em lightly. By the way, that testes thing....it hurts like the dickens.

yes it can leak into the cylinder. that is how mine failed on cylinder #6. I could even be a small leak that only leaks after the engine is warmed up and there is pressure in the coolant system.

My motor was #6 as well, 0.004" of pitted canyon from coolant to cylinder #6. I had the block decked 0.010" (first time was recall at 90K. Seems to me that the replacement headgasket from Toyota is NOT solving this problem. So, the 3.0L saga continues.

Question for the experts: What coolant are people using? Should I avoid the red Toyota coolant?

Thanks, Hugh <img src="/forums/images/graemlins/cheers.gif" alt="" />

Headgasket/cooling link http://www.arrowheadradiator.com/preventing_cylinder_head_gasket_and_cooling_system_failures.htm

Coincidentally, I just finished pulling the cylinder heads off my '95 4Runner today. I also had a #6 failure from the coolant passage to the cylinder. The gasket was pretty much gone there with exception of the fire ring. Toyota also claims my vehicle is not included in the recall either. Interesting, it has the same mode of failure. I'm fixing it myself, but I'm still going to send them a bill to cover parts just for kicks!

My issues started quickly and went from a miss at higher RPM's, to a check engine light code 25, to puking coolant out the overflow reservoir and overheating, all within a couple days.

Coolant can and most certainly will leak into a cylinder if the gasket fails, and in some cases causes hydrolocking of the engine. When the engine is off, coolant drips into the cylinder filling it up. When you start the engine, coolant blows out the exhaust, and there will probably be a miss. If there's enough water, it can't get out fast enough and will bend the connecting rod (or worse). When the engine is running, the force of combustion forces air in the reverse direction through the leaking gasket, and air gets pushed into the cooling system. It will, as in my case, push air into the entire system forcing coolant out the overflow reservoir.

I figured out how to do my own leakdown test to verify which cylinder(s) had a blown gasket. I have another post going in the 4Runner forum about combining a 2 gallon air compressor with a compression gauge to make a makeshift leakdown tool. I used it to pressurize the cylinder in question and see if I could force air from the cylinder into the cooling system. Glub glub glub glub was the sound I heard when I tried it on good old # 6!