PT Radiator Air Scoop

[Scott Forman]

If the scoop pushed more air through the radiator, it could lower
operating temp to the point that the alarmastat doesn't kick in.
More air=cooler, that is the whole point of the fan. I am not
looking for lesson on how the colling system works, and if you payed
attention you would see that I just mentioned that I have a freshly
re-cored (i.e. NOT DIRTY) radiator in my bus. I am looking for
people that have anecdotal stories about scoops, not for people who
are answering every question except the one I asked.

Scott

--- In WanderlodgeForum@yahoogroups.com, Leroy Eckert
wrote:
>
> First the scoop will not cool the radiator any quicker or cooler or
reduce the fan on off sequence because the water temp is controlled
by an instrument *Alarmstat* designated by BB. It the radiator is
plugged up it ain't gonna cool, scoop, extra fans or anything else. 
On most coaches through 1994 there is an Alarmstat which senses the
water temp and activates the fan to high mode and back to idle mode
constantly if the fan override and the chassis a/c is off. It cycles
between -+ 8 degrees. It was specified by BB at 195 degrees.
Accordingly, the fan in idle mode spins between 200 and 600 rpm at
engine rpm values  800-2100 rpm according to my BB manuals. So, if
the radiator is not clean and good massive amounts of air will do not
good the result being the fan will cycle more often. In high mode,
chassis a/c on; or fan override on; the fan runs at approx. 1800 rpm.
The only thing that will stop the fan high/idle mode sequence timing
is a new radiator.
> It makes a lot of sense. Bad radiator, no air flow, no efficient
cooling. A scoop is not going to help a bad radiator. It is that
simple. Of course it may help for a bit if you remove the Alarmstat,
let the fan run constantly and you may see some reduced temps.
> I have jacked with my bus using VMSpc for quite some time and I
cannot prove the old wife's tale that the fan reduces mileage. I have
documents with lots of numbers on them that support my opinion. I
realize opinions are like a$$holes, everyone has one. However, my
numbers prove my statement. I long ago changed my Alarmstat to 190
degrees after talking to BB and Detroit Diesel mechanics. I have seen
a 7% decrease in overall temps without a decrease in mileage. I have
a good radiator.
> My conclusion is, the Birds did not have a problem when they were
built or there would have been a recall. 15-20 year old radiators
need a good going over and all will be well. No scoop needed.
> Think of an Alarmstat as a forced high temp thermostat, because
that is what it is.
>
> Leroy Eckert
> 1990 WB-40 Smoke N Mirrors
> Dahlonega, GA
> Royale Conversion
>
> --- On Wed, 8/6/08, Scott Forman <scottforman75@...> wrote:
> From: Scott Forman <scottforman75@...>
> Subject: [WanderlodgeForum] Re: PT Radiator Air Scoop
> To: WanderlodgeForum@yahoogroups.com
> Date: Wednesday, August 6, 2008, 8:07 PM
>
>
>
>
>
>
>
>
>
>
>
> I do not have a cooling problem, in fact I just re-
cored my
>
> radiator. Just wondering if the scoop could give me the 5 degrees
I
>
> need to keep the fan from kicking on...which as we all know saps
fuel
>
> economy...during hot weather.
>
>
>
> Scott
>
>
>
> --- In WanderlodgeForum@ yahoogroups. com, "Gregory OConnor"
>
> wrote:
>
> >
>
> > Scott, when the engineered systems will no longer control the
heat,
>
> > there is issue with the systems. to make things run cooler at
more
>
> > stress, can only prove to allow more stress than engineered. I
pust
>
> it
>
> > to the limits of heat befor I back off stress. A mod to help
>
> overcome
>
> > ambient temp influence like the radiator evaporative cooler MikeH
>
> uses
>
> > is one mod I would like to try.
>
> >
>
> > GregoryO'Connor
>
> > 94ptRomolandCa
>
> >
>
> >
>
> >
>
> > --- In WanderlodgeForum@ yahoogroups. com, "Scott Forman"
>
> > <scottforman75@ > wrote:
>
> > >
>
> > > There was some talk a while back about fabricating an air scoop
>
> for
>
> > the
>
> > > radiator grill on a PT to increase air flow through the
>
> radiator.
>
> > Did
>
> > > anyone install one? Does it seem to make a difference? How
did
>
> you
>
> > > build it?
>
> > >
>
> > > Scott Forman
>
> > > 86 PT38
>
> > > Memphis
>
> > >
>
> >
>