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Discussion Starter #1
Off and on over the past couple of months, I'll get a few drops of coolant on the garage floor - literally just a few drops. Its dripping on the floor below the rear of the engine closer to the firewall, slightly off center to the passenger side.

There's no rhyme or reason when it leaks. Sometimes I drive hard and no leak, other times just a leisurely drive, and a few drops the next day, and then nothing for a few weeks even tho I drive it regularly on the weekends. Coolant level hasn't really dropped.

I've gotten under there but it happens too infrequently and so little comes out, I can't find it.

Any ideas? What would cause a leak to come and go? Unless it is leaking consistently but vaporizes or pools up some place?

:crazy:
 

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I've seen that happen when you have a small leak in a heater core hose. If you have the temp selector on "hot", then coolant flows through the core. When you turn the selector to "cool" then a valve is closed and no coolant flows through those hoses. Try driving around with the selector on "hot" and see if the leak shows up.
 

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thats wat i was thinking...just check some of the coolant lines back there behind your trans. and if thats not it, it could possibly be power steering fluid coming from the main line behind the intake manifold.
 

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After you check the mentioned heater core lines, you may also want to look at the smaller lines between the water pipe and intake manifold. They are difficult to get to, and many people just remove them all together. I believe they are positioned so that the coolant could leak onto the down pipe, and the majority of the small leak would burn up, causing an inconsistant amount of drips under the car.

Do you ever smell anything burning off the exhaust? If it is a small leak, especially while moving, it would be difficult to see the small amount of smoke it may produce.

Something to look at, keep us posted.
 

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Discussion Starter #5
Damn - the heater core hose sounds like a good bet. The temps in Ral have been as low as the 30s and as high as the 60s. Using the heat or not could be the variable.

I'm going to experiment. I'll drive around for a few days with no heat and then try again using the heater and see what happens.

Excellent hints. Tks.

I'll post up after I figure it out.
 

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I'm just down the road from you. My heater hose just burst a couple weeks ago. The one w/o the valve and connects right above the speed sensor. Very hard to get a grip on. Cheap fix tho. 5/8 hose from AdvancedAuto < $2.50. 2' does the trick. That one gets a sharp bend in it from the speed sensor and wears a thin spot if the hose sleeve isn't in place.
 

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funny my heater hose had a big slit in it. my mamma changed it fo me. I didnt even have to ask. that just goes to show how easy of a fix it is.
 

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funny my heater hose had a big slit in it. my mamma changed it fo me. I didnt even have to ask. that just goes to show how easy of a fix it is.
Your momma fixed it for you? That's one cool momma you got there. :scool:
 

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i just discovered today that I'm having this same problem. I found that the large hose that runs from the bottom of the radiatior to the engine right above the tranny has a crack where it attaches to the engine. your mom wanna come fix mine?
 

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Discussion Starter #11
I could use his momma, too.

I checked my coolant tonight and the reservoir was empty and the radiator level was down. It must've been leaking for awhile . . . gdammit . . .

Tomorrow I don't have to work so I'm gonna get under there and see what's up. I've been driving around without using the heat and no coolant has spotted the cardboard I've left underneath at night. I'll fire it up tomorrow and slide the heater to HOT and see if it starts leaking, Either way, I hope it's easy to track down.

Being that the car is almost 20 years old, I just might replace all the hoses since I'll have the coolant drained.

I just drained and refilled a few months ago. If the coolant still looks pristine, I may re-use it. :hehe:
 

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Discussion Starter #12 (Edited)
So I topped off the coolant and drove around with the heat on. Parked and a couple hours later, nothing dripped onto the clean cardboard. Checked again after a few more hours and nothing. :hmmm: Raised the car and got under it while the engine was running. Couldn't see anything dripping or smell coolant.

I'll check again in the morning and keep an eye on the fluid level.

Grrrrrr . . . Maybe its affected by the tide and the moon. What else would cause it to leak every 3 weeks or so? :grin:
 

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You aren't getting any white smoke out of the exhaust are you?

A compression test would rule out a possible slight leak in the head gasket, other than that, my money would be on those tiny coolant lines behind the intake manifold.

Good luck finding the leak, I'm fighting these tiny leaks with coolant and power steering as well.
 

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Discussion Starter #14
You aren't getting any white smoke out of the exhaust are you?

A compression test would rule out a possible slight leak in the head gasket, other than that, my money would be on those tiny coolant lines behind the intake manifold.

Good luck finding the leak, I'm fighting these tiny leaks with coolant and power steering as well.

Exhaust looks fine. Oil looks and smells OK too so I don't think I'm loosing coolant internally. Good idea on the compression test for peace of mind. I think I'm just going to make an appointment to have another set of eyes check everything out and do the compression test.
 

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Discussion Starter #15
And the answer with 98.5% probability is . . .

. . . the thermostat housing.

There's been no rhyme or reason to the leak.

Brought it to an awesome shop here in Raleigh for a second set of eyes to check it out. Underneath the thermostat there was white crusty build up indicating that it was leaking. He found the deposit by running his finger under it.

The theory is that it was a subtle enough of a leak and it was crusty enough that it was sealing itself and every so often it would pop allowing it to drip. It would have leaked onto the transmission below where it would have dribbled off in front of the passenger where I've found the occasional splatter. There was a couple of white-ish marks on the transmission that most likely is coolant but it was worn off pretty well to tell for sure.

Changed the thermostat gasket and the thermostat, too. Haven't had any problems with the thermostat but as far as I can tell it was the original. There's no maint records it was ever changed and the previous owner gave me everything. It was a preventive measure.

Changed the fluid to Honda blue since the system had to be drained and refilled any way.

Pretty sure this was it but I'm gonna keep an eye on it and the coolant level for awhile to monitor it.

Lesson learned: Finger your thermostat. Finger it hard and often. :upside:
 

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mine leaked in the same place but mine was because the dumbass that owned my car before broke a bolt off in the thermo housing and used rtv to stop it from leaking which it didnt...
 

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Discussion Starter #17
mine leaked in the same place but mine was because the dumbass that owned my car before broke a bolt off in the thermo housing and used rtv to stop it from leaking which it didnt...
That's exactly what he warned me of before they changed it out. Said the bolts might seize. If they were lucky they could drill them out. Worse case scenario, new housing, more tapping and drilling. Luckily they got everything out fine after soaking it in PB Blaster or whatever it was they use.
 

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We had a heck of a time finding the leak on my sons 88. It was such a small leak. Had to put about a quart of Antifreeze every week.
Under the Distributor, stand on the passenger side and look under where the distributor was you will see a Metal "T" with a small hose going to the fuel rail, one going to the right and one straight down. The hose going down had a small pin hole in it and could see it squirt out after building pressure.

They are a real bugger to get to because I didn't have any hand room on the bottom hose and the stupid spring type clamps sucked and could not get the pliers on the lower clamp.
 
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