Dash Riprock
Active Member
- Joined
- April 9, 2005
- Messages
- 72
- Reaction score
- 0
- City, State
- LA, CA
- Year, Model & Trim Level
- 95 Explorer XLT
Hi all, please forgive the long post. I am currently dealing with a coolant leak/cylinder head gasket problem and Ive got a few questions beyond the usual "where is my coolant going" offerings.
Some background: '95 XLT, 160K, 4.0 OHV. This is my wife's car which I never paid much attention to (Im busy, damnit). When I started to, I found the coolant low, and the temp guage never rising much above "C". Odd, I thought. Seems like the two are in opposition to each other. Anyway, I found and fixed a leaking heater control valve, then replaced a stuck open or bypassing thermostat (lots of corrosion), and threw on a new radiator cap for good measure. I thought I had it beat.
And then away went my coolant again. I climbed underneath and found the leak. See the 1st pic. This is forward looking aft, from the right front corner of the car, up at the passenger side engine block. The leak is apparent at the middle exhaust port underneath the manifold. What is amazing to me is the same condition exists on the drivers side, in the same place.
So, I have simultaneous, driver and pass. side leaking CH gaskets. This from a engine that was running abnormally low temps and to my knowledge had never been overheated. No record of pinging, knocking, loss of power all the time this was occuring. In fact, it seems the faulty thermostat may have saved the engine.
My question is, well, wtf? How do both gaskets blow? What would cause this other than overheating. Is it possible to overheat with low coolant all the while the temp guage never showing any movement?
After searching this forum and reading many threads I came away with a few tests I could do. The first thing was I pulled spark plugs (autolite platinums). See pic below, do these look like a coolant in the cylinder situation? I didnt think they did, but Im no expert. The insulators are whitish-tannish with one showing some pink tinges. (The coolant is green) The electrodes do have a whitish-light greyish powder, but they arent encrusted. Both plugs are dry.
Next I tried the cold start with radiator cap off trick to see if the cooling system was being pressurized by compression. Upon starting I got no gusher, no bubbles, no squirts. The coolant did begin to slowly rise though within 10 seconds of the engine start. Is this normal? By ~20 seconds I had to shut down or the coolant would have started seeping over the filler neck. I revved the engine as well.
I was not able to perform a compression test. By the indications on these simple tests, It seems that I have a externally leaking only, blown head gasket. It does not appear to be going to the cylinder. No white smoke, no exhaust smell. Last weeks oil change showed no milkiness. Oil level is not rising artificially. The problem is, how can cooling system pressure alone blow a gasket, correction, TWO gaskets!? Is there some way to overpressurize it that the rad. cap wouldnt vent?
Finally, I have one last very important question. How long can I survive like this and how long can I go before it has to be fixed for real. I need this thing to last through a long camping trip and I dont have time now to dive into it, if I decide to do that at all. Ive seen mentioned many times this "Bars Leaks" stuff and bought some last night. I have not used it yet. Will this help or hurt, does anyone have any experience with it? The only way I can descibe the severity of the leak is to note that it consumes one overfill/catch tank full every week of normal work driving (10 hours) . And each time it is empty, removing the rad. cap reveals the coolant full up to the neck.
Thanks for reading this novel. I appreciate your replies and advice. I just put a reman'd tranny in this a year ago too, and am now torn between selling it and losing that investment in the trans, not to mention the huge project of fixing the CH gaskets.
Some background: '95 XLT, 160K, 4.0 OHV. This is my wife's car which I never paid much attention to (Im busy, damnit). When I started to, I found the coolant low, and the temp guage never rising much above "C". Odd, I thought. Seems like the two are in opposition to each other. Anyway, I found and fixed a leaking heater control valve, then replaced a stuck open or bypassing thermostat (lots of corrosion), and threw on a new radiator cap for good measure. I thought I had it beat.
And then away went my coolant again. I climbed underneath and found the leak. See the 1st pic. This is forward looking aft, from the right front corner of the car, up at the passenger side engine block. The leak is apparent at the middle exhaust port underneath the manifold. What is amazing to me is the same condition exists on the drivers side, in the same place.
So, I have simultaneous, driver and pass. side leaking CH gaskets. This from a engine that was running abnormally low temps and to my knowledge had never been overheated. No record of pinging, knocking, loss of power all the time this was occuring. In fact, it seems the faulty thermostat may have saved the engine.
My question is, well, wtf? How do both gaskets blow? What would cause this other than overheating. Is it possible to overheat with low coolant all the while the temp guage never showing any movement?
After searching this forum and reading many threads I came away with a few tests I could do. The first thing was I pulled spark plugs (autolite platinums). See pic below, do these look like a coolant in the cylinder situation? I didnt think they did, but Im no expert. The insulators are whitish-tannish with one showing some pink tinges. (The coolant is green) The electrodes do have a whitish-light greyish powder, but they arent encrusted. Both plugs are dry.
Next I tried the cold start with radiator cap off trick to see if the cooling system was being pressurized by compression. Upon starting I got no gusher, no bubbles, no squirts. The coolant did begin to slowly rise though within 10 seconds of the engine start. Is this normal? By ~20 seconds I had to shut down or the coolant would have started seeping over the filler neck. I revved the engine as well.
I was not able to perform a compression test. By the indications on these simple tests, It seems that I have a externally leaking only, blown head gasket. It does not appear to be going to the cylinder. No white smoke, no exhaust smell. Last weeks oil change showed no milkiness. Oil level is not rising artificially. The problem is, how can cooling system pressure alone blow a gasket, correction, TWO gaskets!? Is there some way to overpressurize it that the rad. cap wouldnt vent?
Finally, I have one last very important question. How long can I survive like this and how long can I go before it has to be fixed for real. I need this thing to last through a long camping trip and I dont have time now to dive into it, if I decide to do that at all. Ive seen mentioned many times this "Bars Leaks" stuff and bought some last night. I have not used it yet. Will this help or hurt, does anyone have any experience with it? The only way I can descibe the severity of the leak is to note that it consumes one overfill/catch tank full every week of normal work driving (10 hours) . And each time it is empty, removing the rad. cap reveals the coolant full up to the neck.
Thanks for reading this novel. I appreciate your replies and advice. I just put a reman'd tranny in this a year ago too, and am now torn between selling it and losing that investment in the trans, not to mention the huge project of fixing the CH gaskets.