Hello all,
Driving older vehicles (by choice, mo$tly) I keep a close eye out for signs of leaks. My 90 Sentra has long had seeping oil leaks, so intermittent drips of old crud don't scare me; if it becomes common, I take notice, clear oil on the ground is a call to battle stations.
I have had the car since it was new, but the truck I bought just over a year ago. In that time, it has barely made a mark on its part of the driveway. I find this odd because it has some signs of minor leaks, but I can live with it :)
Today, I started to leave for an errand and noted a fairly large wet area under where it had been sitting; fortunately, I did not pass it off as rain water. It was from the right side, and felt a little oily. I hate to admit it, but my first reaction was "it's not coolant." A flashlight from the top didn't reveal much. A little oily patch here or there, but nothing scary, all consistent with the engine's normal condition, and nothing that would explain the "spill."
I didn't see much from below, until what I now think was coolant dripped on my arm, and I noticed the trickle leading back up to what I am assuming is the heater core. The hoses inside the engine compartment look fine. So far, I do not see any signs of coolant inside the cab; is that something that I should expect to find, or does the cover arrange for it to fall (forgive the ravings of a green mechanic) between the cab and the wheel well, or something like that? Please feel free to correct my anatomical references as appropriate.
The only other thing that comes to mind is that it _could_ be some dyed fluid from the AC system. I doubt it, but I will mention it. The AC was working fine recently, though I had no use for it today. I do not know whether it has dye in it.
It appears not to leak very much when the engine is not running. Does that tell you anything?
Assuming it is the core:
Haynes says to disconnect the negative battery cable. I'm happy to do it, but am wondering why that would be necessary. There is also mention in both Haynes and the Ford shop manual about vacuum connections. It might make sense when I get into it, but any pointers to what is going on would be appreciated. Partly curiosity, and partly wondering what I am getting into.
Since the core seems a likely offender and apparently costs all of $22, I am off to get one before it sells, and to have it on hand for when I tear into it (probably tomorrow). With that said, is there anything else you would consider as a source of the leak? My plan is to remove the glove box and then put a pressure tester on it to hopefully prove the core is the problem. Is there any problem with that approach? Does removing the glove box ask for trouble with the battery connected? Any other risk?
Haynes also says to drain the coolant. Again, no problem, but is it really necessary? The heater hoses are high in the system, and can be covered and supported high enough to prevent lots of coolant loss. The coolant looks fairly clean after my relatively recent water pump and radiator adventures, so I am inclined to avoid creating a lot of waste just yet. It seems that I should be able to get away with losing only what spills before I get control of the hoses and a little more installing the new core. Please let me know if I am missing something.
Is there anything else I should be asking? You might recall advising me on replacing the shocks, thermostat, water pump, and radiator. Translation: I know just enough to be dangerous :) Cautions and hints will be gladly accepted.
Thanks,
Bill