Not to belabor the point, but on many engines, the thermostat also controls
a valve that bypasses directly to the water pump suction when the engine is
cold. This makes the engine warm up a lot faster, which is good for
emissions. I'm not sure how far this goes back, but I know that the
current (until last year at least) 350 and 454 have this feature and they
have had it for at least 20 years. The inline 6's don't. The modern V 6's
and 4's do. I seem to remember the bypass hose (the little L shaped hose
between the thermostat housing and the water pump) starting in the late
60's or early 70's.
It's easier for the water to go through the open bypass than through the
radiator. Pull the thermostat and the radiator stays bypassed when the
engine is hot and the engine overheats.
Bruce Kettunen
57 3200
Mt. Iron, MN
>Bruce
>
>Higher flow will dump more btu's but only to a point.
>Am not sure why (avoided the thermal dynamics class).
>I can only talk from experiance.
>
>Have seen a couple of vehicles where someone pulled
>the thermostat and then it overheats on the highway.
>Faster you go the faster it heats up. Put in a new
>thermostat and they where just fine. Run down the
>highway all day long no problem. My cousin a Chevy
>mechanic said the thermostat acts as a restriction and
>slows the coolant down. Laughed 1st time I asked him
>about it. Said he has seen it more than once.
>
>Steve
>Howell, MI
>
>Household fleet manager
>97 Villager wife's
>94 Sundance (170,000 miles) my comuter
>89 Mitsubishi daughter's
>83 F**d F250 son's
>74 Cuttlass mine and son's project
>looking for the right AD or TF
>
>--- B&A Kettunen <bekett@uslink.net> wrote:
>> I've heard about the slower water pump allowing more
>> cooling, never tried
>> it. The engineer in me says that slower flow will
>> produce cooler exit
>> water, but less of it. The higher flow will produce
>> warmer water, but more
>> of it. Net result is that higher flow should dump
>> more heat (btu's) from
>> the radiator and cool better. This is for what it
>> is worth. We have a
>> shop in town that engineers heavy equipment
>> radiators from scratch and
>> builds them as replacement for Cat, Lectra Haul, and
>> others. I'll give
>> their engineering department a call on Monday about
>> this.
>>
>> Bruce Kettunen
>> 57 3200
>> Mt. Iron, MN
>
>
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