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I noticed the other day that my 1981s passenger floor mat was wet. But I do not think it is water. I removed the top mat and the carpet was wet, so I pulled that back and the sound deadening material was soaked. To the touch this wetness feels viscous but is clear. No significant odor. I accidentally tasted it and it was a little bitter. Hard to say where this came from or how long it has been there. It does not appear to dry out with a fan blowing on it. Any suggestions?
It's half water. It's almost certainly a leaking heater core.
You should feel a difference. Just don't taste it. Coolant should be sweet, but is poisonous. Perhaps the bitterness comes from the jute backing under the carpet.
To check for a heater core leak:
With the car completely cool, squeeze the upper radiator hose. If it has no resistance, there is a leak in the coolant system somewhere.
Fill the coolant and monitor the level. If you have even a slow leak, the overflow coolant tank will maintain a more constant level when the car is hot and cold. As when the coolant gets hot, it will leak thru the opening in the heater core, instead of going in the coolant tank. As the coolant cools, air will be sucked in thru the heater core, instead of pulling coolant from the overflow tank.
Last edited by mark79,80; May 7, 2024 at 07:04 PM.
Rookie advice:
Vaccum up as much liquid as possible and pur it into a glass jar-does it still look clear and "viscous".
You may have to remove the passenger kick panel to spot running leaks in that area.
Place a piece of large cardboard on the floorboard bent to the shape of the firewall/floorboard.
Then cover with a few pieces of blue paper shop towels (use tape if needed to hold the towels in place.
Drive the car a few miles with the engine at operating temperature until you notice drip spots on the blue paper towels.
Then use a spare blue paper towel to dab the area (air box/ducting/etc) above the leak until you see wet spots on the paper towel.
If there were no wet spots at all on the paper towel after the 1st test...take a water hose and wet different exterior areas/one area at a time with the hood closed while you look for drips on the paper towels.
If there are still no leaks...raise the hood and spray water in the rain trough while watching the paper towels...
Still no leaks...spray water on the firewall and check the towels.
Stii no leaks...spray water around the windshield...check towels for drips
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Originally Posted by Bikespace
It's half water. It's almost certainly a leaking heater core.
You should feel a difference. Just don't taste it. Coolant should be sweet, but is poisonous. Perhaps the bitterness comes from the jute backing under the carpet.
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another vote for radiator fluid....pull your carpet and wash it out with fresh water...if you leave it it will eat through the carpet eventually and you will be pulling it any way to replace it. You can just take the heater hose off at the core and loop it back to the engine so you can deal with it later
I noticed the other day that my 1981s passenger floor mat was wet. But I do not think it is water. I removed the top mat and the carpet was wet, so I pulled that back and the sound deadening material was soaked. To the touch this wetness feels viscous but is clear. No significant odor. I accidentally tasted it and it was a little bitter. Hard to say where this came from or how long it has been there. It does not appear to dry out with a fan blowing on it. Any suggestions?
Are you driving like a maniac with a passenger? That might suggest the liquid in the floor.
I'm pretty sure that any fluids dumped on the floor, by rain, or a passenger, would evaporate with a fan blowing over them. The ethylene glycol in the antifreeze is what's on the floor now, from the heater core.
OP, if you want to bypass the coolant loop, you'll need to cut the hoses, and use a 5/8 to 3/4 adapter to join the ends in a short loop (from the intake manifold to the pump inlet). Or you can install two valves, if you intend to repair the heater core, or you can install two pipe plugs if you don't want to worry about this right now.
If you are 90% sure it's the core at fault, you can buy some time and do a temporary repair, cheap.
Like Bikespace said, try to find the adaptor at a local auto parts store. Black plastic pipe, 5/8" on one end, 3/4" on the other end. Exact same as your heater hoses.
Its just a matter of putting the front end up on ramps, drain some coolant off, disconnect both hoses at the core, insert the special splice and clamp.
If you can get at the hose clamps, you don't even have to cut the hose.
I believe Dorman has the part you need. This approach is a whole lot easier than removing the hose fittings at the W.P. and the Intake, then inserting pipe plugs.
To bypass the heater core, you can also purchase brass barb plugs. Cut each heater hose leaving a short section, where they come from the intake manifold and water pump, insert the barbs, securing them with hose clamps.
You can then clean up the engine compartment by cutting away the hoses. If you eventually replace the heater core, you would most likely be replacing the heater hoses anyway.
I like this better than removing the barbed fittings from the intake manifold and water pump as there is a chance of damaging the threads on the aluminum intake manifold when removing the steel barb, to thread in a plug.
This also has a cleaner look than having heater hoses connected to a bypass fitting.
HI All,
Good morning. Just a little on the damp side in Paradise. Are the heater hoses different sizes?
The one from the Manifold:
The one from the Water Pump:
Thanks,
Fred
Passenger floor wet
