"fbksdodge" <u41008@uwe> wrote in message news:7ee68ec45ffef@uwe...
>i have a 88dodge grand caravan that isn't putting out any heat!! there is
> snow and ice INSIDE my van it's that cold. I'm thinking it's my thermostat
> what do you say??
>
If there's a problem with the thermostat, either the engine would overheat
or would take an awfully long time to warm up. (Do you know the history of
the vehicle? It's possible that it might not have any thermostat at all, if
a previous owner went cheap -- and stupid -- on fixing an overheating
problem...)
With an old vehicle, look under the hood to see if it's got a valve
controlling coolant flow to the heater. (Some vehicles have the heater on a
"full flow" system with no valve in the line and water constantly flowing
through the heater core, and some have a valve that opens the flow to the
heater core only when you select "heat" from the dash controls.) If it's got
that valve in (or at one end) of one of the heater hoses, it very well could
be rusted shut. Simplest solution is to remove the valve and re-connect the
heater hoses as a "full flow" system. (I've done it -- it works.) If you
remove the valve, just remember to block off the vacuum line that activated
it...
If it's a "full flow" system, you could have accumulated corrosion blocking
flow to or through the heater core. Since a corroded cooling system could
very well screw up the thermostat as well, you could try a cooling system
flush (a good one, with the nasty corrosive chemicals & neutralizer, not the
cheap stuff you find in Wal-Mart) along with a new thermostat... (If the
system is that far gone, you might want to install new heater hoses as well.
It's possible for them to start disintegrating internally, tossing off bits
& pieces that block flow, even if they aren't leaking internally yet.)