Terminal experiment #3762...who needs a fan?

[Hachiroku $B%O%A%m%/(B]

So, just for laughs I removed the mechanical fan from my Sube GL (89 Coupe)
Ambient temp today was about 52 degrees, normal for this time of year.
Temperature ran warm until the thermostat opened, and then...ran
absolutely normal.

However, the low end grunt from the engine was better, throttle response
was better, and the car just seemed to run easier without it.

Hmmm...

The electric fan is still installed and when last tested 2 months ago was
working perfectly.

 

[Ashton Crusher]

So, just for laughs I removed the mechanical fan from my Sube GL (89 Coupe)
Ambient temp today was about 52 degrees, normal for this time of year.
Temperature ran warm until the thermostat opened, and then...ran
absolutely normal.

However, the low end grunt from the engine was better, throttle response
was better, and the car just seemed to run easier without it.

Hmmm...

The electric fan is still installed and when last tested 2 months ago was
working perfectly.

Yeah, at 52 Degrees it's probably ok. They have to design the vehicle
for places that will get up to 115 degrees.

 

[Don Stauffer]

So, just for laughs I removed the mechanical fan from my Sube GL (89 Coupe)
Ambient temp today was about 52 degrees, normal for this time of year.
Temperature ran warm until the thermostat opened, and then...ran
absolutely normal.

However, the low end grunt from the engine was better, throttle response
was better, and the car just seemed to run easier without it.

Hmmm...

The electric fan is still installed and when last tested 2 months ago was
working perfectly.

Most racing cars do not use fans. Of course, they are not called upon
to idle very long.

Fans really get called into play for long periods of idle, or in very
slow driving traffic. In fact, I have seen cars in days of mechanical
fans that had a limit on how long they would idle in warm weather
without overheating.

I used to work in a gas station when I was a teenager, and one of my
jobs was responding to folks who had locked themselves out of car.
You'd be surprised how many did so with engine running! In most cases,
by time I got there the car was overheating. This was in fifties.

The regular simple belt driven fan was replaced in some cars by the
clutched fan that would freewheel above a certain engine speed, so it
could be turned with a better ratio at idle. Of course, when they went
to transverse engines the electric fan with thermostat came along.

In the hot rod era of fifties and sixties the clutched fan was very
popular, but many just took the simple route (cheap) and removed fan.
Had to avoid more than a couple of minutes of idle, of course.

 

[Nate Nagel]

Most racing cars do not use fans. Of course, they are not called upon
to idle very long.

Fans really get called into play for long periods of idle, or in very
slow driving traffic. In fact, I have seen cars in days of mechanical
fans that had a limit on how long they would idle in warm weather
without overheating.

I used to work in a gas station when I was a teenager, and one of my
jobs was responding to folks who had locked themselves out of car. You'd
be surprised how many did so with engine running! In most cases, by
time I got there the car was overheating. This was in fifties.

The regular simple belt driven fan was replaced in some cars by the
clutched fan that would freewheel above a certain engine speed, so it
could be turned with a better ratio at idle. Of course, when they went
to transverse engines the electric fan with thermostat came along.

In the hot rod era of fifties and sixties the clutched fan was very
popular, but many just took the simple route (cheap) and removed fan.
Had to avoid more than a couple of minutes of idle, of course.

The nice thing about clutch fans is that they can be made to tighten up
when the engine gets hot.

Unfortunately, the thermostatic style are not available anymore for old
Studebakers (nose of the water pump is very large compared to a typical
GM engine, so you can't just use someone else's) so I personally am
stuck with the type you describe that just limit the max speed of the
fan, which makes for a noisier and less efficient drivetrain.

I see a lot of hot rodder types removing the engine fan completely and
using an electric, but I'm not completely sold on the idea that the
electrics can move enough air for a 300+ HP engine, especially when
using a radiator that was designed for a lower output engine.

I do know that some cars, e.g. a Porsche 944, actually require some sort
of fan (although that car does use an electric fan only) due to the
aerodynamics of the car; it doesn't naturally draw enough air through
the radiator even at highway speeds to keep the engine cool in warm weather.

nate

 

[hachi]

Yeah, at 52 Degrees it's probably ok. They have to design the vehicle
for places that will get up to 115 degrees.

I went for an 'extended' ride this AM (~55 degrees and soggy) and the
temp never moved from the thermostat region.

And I also increased fuel economy.

I don't think you followed the 'history' of this car like the guys in
Subaru. It began overheating in the sring; not overheating but running
warmer than usual. The fan was not 'locking up' as it should when warm,
so I filled it with some silicone oil I had (not the real deal) and
reinstalled it. It was running more than usual, but was stiffening with
an increase in temp, but not really loosening at the proper temp.

Then I realized the radiator was totally shot and bought a brand new
replacement on eBay for a whole $20. Yup...that was it...

I can fell increased performance (since the fan was almost a constant
drain on the motor) and fuel economy seems to be better.

 

[fred]

I do know that some cars, e.g. a Porsche 944, actually require some sort
of fan (although that car does use an electric fan only) due to the
aerodynamics of the car; it doesn't naturally draw enough air through
the radiator even at highway speeds to keep the engine cool in warm
weather.

Yes, the classic example of this is the 917 racing car. Great laugh the
first time you see it and know what it is.
Due to the twin 911 engines stuck together of course.

 

[Steve W.]

The nice thing about clutch fans is that they can be made to tighten up
when the engine gets hot.

Unfortunately, the thermostatic style are not available anymore for old
Studebakers (nose of the water pump is very large compared to a typical
GM engine, so you can't just use someone else's) so I personally am
stuck with the type you describe that just limit the max speed of the
fan, which makes for a noisier and less efficient drivetrain.

I see a lot of hot rodder types removing the engine fan completely and
using an electric, but I'm not completely sold on the idea that the
electrics can move enough air for a 300+ HP engine, especially when
using a radiator that was designed for a lower output engine.

I do know that some cars, e.g. a Porsche 944, actually require some sort
of fan (although that car does use an electric fan only) due to the
aerodynamics of the car; it doesn't naturally draw enough air through
the radiator even at highway speeds to keep the engine cool in warm
weather.

nate

Nate, Find a thermo unit you like and have it bored to fit the snout.
Shouldn't cost over 15 bucks to do it on a lathe.
OR if you have an extra 3/4" or so you could have a step adapter made up
to go between them.

Electrics depend a LOT on the design of the blades. I've used electrics
on most of my vehicles and many of those were well over 300 HP...

 

[Nate Nagel]

Nate, Find a thermo unit you like and have it bored to fit the snout.
Shouldn't cost over 15 bucks to do it on a lathe.
OR if you have an extra 3/4" or so you could have a step adapter made up
to go between them.

It's been tried - there's not enough meat on a Ch*vy clutch fan to bore
it without making it dangerously thin; I don't have *any* extra space
for a spacer as I am pretty much throwing parts that were never intended
to work together at this car - right now it's a '55 coupe with a '63 R1
engine and a fan from some year GTO on a repro Stude clutch. Clearance
between fan and shroud is almost nonexistent; you have to be real
careful reinstalling the shroud or the fan will hit when you shift or brake.

nate

 

[1 Lucky Texan]

It's been tried - there's not enough meat on a Ch*vy clutch fan to bore
it without making it dangerously thin; I don't have *any* extra space
for a spacer as I am pretty much throwing parts that were never intended
to work together at this car - right now it's a '55 coupe with a '63 R1
engine and a fan from some year GTO on a repro Stude clutch.  Clearance
between fan and shroud is almost nonexistent; you have to be real
careful reinstalling the shroud or the fan will hit when you shift or brake.

nate

Anyway to shave some material off the blades to help with clearance?
Or remoun tthem on the arms or something?

 

[Scott Dorsey]

It's been tried - there's not enough meat on a Ch*vy clutch fan to bore

ke.

That's bad. I would have recommended one of the BMW clutches, which you
could probably machine an adaptor for. But they are just naturally pretty
deep. No way you can move that radiator forward a touch?
--scott

 

[Ray O]

It's been tried - there's not enough meat on a Ch*vy clutch fan to bore
it without making it dangerously thin; I don't have *any* extra space
for a spacer as I am pretty much throwing parts that were never intended
to work together at this car - right now it's a '55 coupe with a '63 R1
engine and a fan from some year GTO on a repro Stude clutch. Clearance
between fan and shroud is almost nonexistent; you have to be real
careful reinstalling the shroud or the fan will hit when you shift or
brake.

nate

Anyway to shave some material off the blades to help with clearance?
Or remoun tthem on the arms or something?

****************
I think that trying to shave material off of the blades would be pretty
difficult without putting the blades out of balance. It would be easier to
fabricate a shroud out of sheet metal or a section of a plastic drum.

 

[Steve W.]

Nate, Find a thermo unit you like and have it bored to fit the snout.
Maybe talk to the outfit that made the clutch and see if they could
alter it for you.

Another possible thing would be to machine a ring to set the fan back
off the clutch.
Running that tight for clearance I would come up with something before I
wiped out a radiator.


Steve W.

 

[Nate Nagel]

Anyway to shave some material off the blades to help with clearance?
Or remoun tthem on the arms or something?

Not in the fore-aft direction. The fan shroud has an almost vertical
part between the radiator and fan, the nose of the car being very low
and the center of the rad. being below the center of the water pump.
hard to describe but here's a pic:

http://members.cox.net/njnagel2/thermostat/thermostat.html

(scroll down a couple, you'll see what I mean)

only thing I would think would help would be a fan with back-swept blade
tips. but anyway the repro *works* it's just not as efficiently elegant
as the original thermostatic one. I actually still have it, and I did
find a guy on the web that supposedly rebuilt ones for GM brand cars,
but he didn't reply to my email asking if he'd be willing to go through
my Studebaker one

Anyway the car runs and cools as is, so it isn't really on my things to
do list.

nate

 

[Nate Nagel]

Maybe talk to the outfit that made the clutch and see if they could
alter it for you.

Another possible thing would be to machine a ring to set the fan back
off the clutch.
Running that tight for clearance I would come up with something before I
wiped out a radiator.


Steve W.

oh, the fan is nowhere near the rad, it's the shroud that is the
problem. we're talking about a '55 Stude, with the low front end. you
*NEED* the shroud on that thing...

worst case I could probably make a custom shroud with more clearance,
but I have other things to do first, like get the @#$% thing back on the
road.

nate