Rik,
The 180 thermostat is proper and will allow the coolant time to be cooled in
the radiator. I strongly discourage use of the 160 thermostat, and no
thermostat. Make sure the fan shroud is there and complete around the fan.
If not, just make one out of tin. It MUST BE THERE! Make sure there are no
obstructions to air flow, front, rear, or in the fins of the radiator. Make
sure the fan blades are complete, straight, AND NOT CAKED WITH DIRT!
The radiator should have it's intake (top) tank removed and checked for tube
blockage build up. It should not cost more than $80 to $135 to have the
radiator top tank removed, core cleaned, tank reinstalled, and the radiator
leak checked and painted.
The four most common causes of overheat are clogged radiators, stuck-open
thermostats, bad fans and wrong timing. Seldom if ever does a water pump
fail to pump or cavitate. Once overheated, the thermostat is always ruined
and must be replaced.
If you have a fan clutch, check the front small temperature coil for any
discharge. If the little coil is dirty with ANY gooey-like grease-dirt, the
fan clutch has failed. Remember, fans cannot duplicate more than about a 35
mph air flow and are primarily designed for air flow at that speed or less.
The fan clutch is also active in airflow draft affected problems in heavy
traffic at higher speeds and also at high temperatures. I don't like flex
fans on truck-type usage engines. They are great on your hot rod with no
a/c.
Fans are belt-driven. A clutched and non-clutched fan often is turning at
insufficient RPM due to simple loose or wrong application belts. Check that
belt. Is it really the correct pitch filling up the pully or is it bent down
and inside the groove? Is it really actually loose and slipping? Look at the
feed-side slop. It should be smooth and not vibrating. Did anyone retighten
it after first new installation? They stretch! That is why modern engines
all use serpentine belts on a floating tensioner.
The most common overlooked heating problem I find is timing. Even a good
mechanic will rely on the timing marks of the harmonic balancer. The
harmonic balancer is a vulcanized-pressed heavy weight round chunk of metal
rubber mounted on the crankshaft hub. IT WILL AND DOES CRAWL! I seldom see a
harmonic balancer that has not slowly crawled on it's hub, thus making all
the timing references wrong! Easy to check, a motor timed using wrong
markings will run so hot the exhaust manifolds will have a dull red glow at
night. When the motor is hot, does it seem during starting that the battery
or starter or both are weak or struggling, maybe you have to pump it, etc.,
but none of this when the engine is cold? When shutting it off, does it tend
to want to continue to run? Is it sensitive to needing premium fuel? Does
the engine seem to run hot? All these can be blatant signs of timing being
wrong, and it only takes just a little bit of wrong!
Every engine should run a 50/50 mix of DISTILLED WATER and antifreeze. It
will make the engine run cooler! NEVER use tap water. Distilled water will
also clean up a system that has not had distilled water. It will clean it up
good, and without the horror of acids! Manufacturers DO NOT use distilled
water in your new car. It saves them at least one dollar per vehicle! They
do however REQUIRE replacement parts such as water pumps be used only with
distilled water or the warranty is VOID!
IF YOU USE DISTILLED WATER AND ANTIFREEZE, CHANGE THE SOLUTION EVERY 24
MONTHS, YOU WILL NEVER EVER HAVE A DIRTY RADIATOR OR ENGINE SYSTEM AND
HEATER! I PROMISE THIS IS TRUE! All the components, especially the
thermostat and water pump will double in life.
-Eddie- Houston TX
> I will toss this out in hopes that someone in the Airstream Brain
> Trust will have an answer for me.
>
> I have a 1983 310 motorhome. Two, in fact, also a 1983 Winnebago
> Chieftain with the same Chevy P-30 chassis and 454 motor as the
> Airstreams. The Chieftain has always run nice and cool, with the temp
> usually at about 1/4 on the gauge, unless it is a hot day or she is
> working hard. One of the Airstreams is recently overhauled, and always
> seemed to run hot. I asked the mechanic that did the overhaul about
> it, and he said it had a new 180 degree thermostat, and the higher
> temp was normal.
>
> My current problem is, Airstream #2 is now being overhauled in Santa
> Ana, CA, while I live in Santa Cruz, about 400 miles away. The
> mechanic is worried because he says it is running hot after the
> overhaul. He also put a new 180 degree thermostat in. It doesn't boil
> the coolant out, just runs hotter than he likes.
>
> Do I tell him to not worry about it, or let him put in a new $500
> radiator, which is what he wants to do? It isn't the money so much as
> the likelihood that it will be the same after the replacement radiator
> as it was before.
>
> Can any of you Airstream motorhome owners out there shed some light on
> my problem? Thanks in advance.
>
> Best regards,
>
> Rik