Big radiator tube shrinks when switching modes on heater from vent to defrost


Asked by Sep 21, 2014 at 06:36 AM about the 1990 Lincoln Town Car Base

Question type: Maintenance & Repair

Refreshing coolant after heater core replacement. Add 1,5 gallon of distilled water in
radiator to flash to remove residues of old coolant. Put heater on max in mode "vent".
Start engine. Then after 10-15 minutes of engine idling, I've turned heater mode from
"vent" to "defrost' and upper radiator tube shrinks extremely and engine sound is
changing. Coolant temperature is always in normal. And bubbles always coming out in
coolant reservoir. By the way one of heater core tubes that goes "in" is hard and hot,
but other tube that goes "out" is quite soft. Any versions? Thank You!

4 Answers


But hose and termostat are new


took that down just as you posted because I got to -re'thinking it, and not so sure of myself, Your statement proves it, I was wrong. so.. the hose collapsing is from when radiator dumps coolant in to overflow and creates a vacuum. Maybe a new radiator cap, could be that simple because since it's not overheating the cap should hold the pressure and not dump in to overflow tank

2 out of 2 people think this is helpful.
Best Answer

As far as the part about the heater core hoses, the one going in is pressurized and hot, but after passing through core, which is just a small radiator, it's cooler and not as much pressure

2 out of 2 people think this is helpful.

Sounds like you possibly have some air trapped in the cooling system.

2 out of 2 people think this is helpful.

Your Answer

Add photo

Related Questions

Town Car

Looking for a Used Town Car in your area?

CarGurus has 2,408 nationwide Town Car listings starting at $1,542.


Search Lincoln Town Car Questions

Lincoln Town Car Experts

#1 FordNut
Reputation 1,520
#2 Tracy Hooks
Tracy Hooks
Reputation 1,320
#3 Tom Demyan
Tom Demyan
Reputation 1,280
View All

Related Models For Sale

Used Mercury Grand Marquis"
52 Great Deals out of 2,580 listings starting at $1,300
Used Lincoln Continental"
1,860 listings starting at $42,501
Used Ford Crown Victoria"
8 Great Deals out of 1,633 listings starting at $1,950
Used Cadillac DeVille"
2,392 listings starting at $1,600
Used Ford F-150"
3,170 Great Deals out of 215,803 listings starting at $1,000

Used Cars For Sale

2011 Lincoln Town Car For Sale
4 Great Deals out of 81 listings starting at $4,999
2010 Lincoln Town Car For Sale
50 listings starting at $4,000
2009 Lincoln Town Car For Sale
82 listings starting at $9,895
2008 Lincoln Town Car For Sale
4 Great Deals out of 90 listings starting at $2,995
2007 Lincoln Town Car For Sale
11 Great Deals out of 210 listings starting at $2,995