HVX Mods & Oil Cooling

Dear Buglover,

Yes.* The idea of using #4 as a restrictor to increase either flow or
pressure has merit.* But I do NOT think the purpose was to improve
oiling of the main bearings.* As you know, the main bearings are the
source of pressurized oil for the connecting rods, although not on a
full-time basis.* The oil passageways in the rods and in the crank
only align every 180 degrees, indicating that these bearings do not
require a great deal of oil for proper lubrication. (Indeed, this is
generally true for all plain bearings._

I think the purpose of the restrictor is to increase the flow of oil
through the oil COOLER.* As partial support for this idea is seen in
WHEN VW began installing the #4 plug in this fashion, that is, the
1600 engine was known to have problems keeping itself cool, especially
in tropic climates such as Brazil, whereas there's no history of
lubrication failures.

With the HVX mods the oil cooling system is modified in that ALL of
the oil flows throiugh a low-restriction oil cooler (ie, the Mesa-
type).* In a vehicle, the flow to the oil cooler is usually governed
by a thermostatic valve which by-passes the oil cooler until the oil
temperature reaches approximately 180 degrees.* In an airplane, the
temperature is controlled MANUALLY.* The pilot opens or closes a set
of shutters which controls the flow of cooling air throuigh the oil
cooler.* Using manual control is a bit old fashioned but it removes a
component from the system (ie, the thermostatically controlled valve)
and gives the pilot the ability to pre-configure the cooling system
prior to take-off (ie,* OIL COOLER - OPEN ).* With a big engine (and
at least a quart more oil) you've got a lot of waste heat to manage.*
Prior to take-off you can get stuck behind some guy doing his nails
and it may be twenty minutes before you're cleared for take-off --
plenty of time for your Oil Temp to creep into the red. Your take-off
run will bring it down a tad but you're at full throttle and as soon
as you begin your climb-out your oil temp will start to rise, Since
the angle of the aircraft will reduce air-flow through the oil cooler,
you'll want to keep your climb-out rather flat.

If you're just doing Bumps & Grinds out of some cow pasture you'd
probably have the oil cooler in the circuit all the time.* But if
you're actually going to FLY somewhere, configuring the engine for
optimum performance at your cruising speed & altitude is critical,
since it effects how much fuel you'll burn... which dictates how far
you can fly.* Once you are at your cruising altitude your oil temp
will tend to be too cold.* So you partially close the shutters until
it's back in the green.* Ditto for a long descent, during which the
engine will tend to cool off.

NOTE: Once you reach your cruising altitude there are a number of
chores to do, adjusting the mixture control and oil temp to give you
the best performance at the lowest rpm. These tasks are usually
referred to as housekeeping. Once you've done the housekeeping, if
you follow the 'official' airways, you can look forward to about three
hours of boredom mixed with a few minutes of total terror, when your
puddle-jumper is overtaken and passed by larger, heavier, faster
airplanes, some of which think it's great fun to see how close they
can come to your wing tip. However, with a GPS that fits in your
shirt pocket you're no longer bound to the airways, allowing you to
pick a route that takes advantage of the prevailing winds. But you'll
probably do what most us puddle-jumper drivers do: simply follow the
railroad track. :-)
------------------------------------------------------------------------------

With vehicles you can't always count on the forward motion of the
vehicle to provide enough air-flow through the cooler.* Installing an
auxiliary fan is the usual solution, although there are designs out
there which utilize part of the output from the engine's blower to
cool the oil.* This is similar in concept to the stock configuration
but on a much larger scale.* (See Jake Raby's web site).

-R.S.Hoover

---------------------------------------------------------------------------------------------------------------------------

Bob, I am following your instructionsand learning much. I have a
question as the longer plug to the #4 bearing is supposed to be a flow
balancer/ restricter to the # 4 bearing so most of the oil goes to the
crank/cam bearings. This is according to a forem on the samba. It
appears to me that the idea has some merit. I have pulled the plug and
tapped it according to your and several others instructions. I have
done the HVX oiling mods, ( I am at the jugs now.) any thaughts to the
idea? PS thanks for the help. Hope you get
better.

Bob Hoover schreef:
> Dear Buglover,
>
> Yes. The idea of using #4 as a restrictor to increase either flow or
> pressure has merit. But I do NOT think the purpose was to improve
> oiling of the main bearings. As you know, the main bearings are the
> source of pressurized oil for the connecting rods, although not on a
> full-time basis. The oil passageways in the rods and in the crank
> only align every 180 degrees, indicating that these bearings do not
> require a great deal of oil for proper lubrication. (Indeed, this is
> generally true for all plain bearings._
>
> I think the purpose of the restrictor is to increase the flow of oil
> through the oil COOLER. As partial support for this idea is seen in
> WHEN VW began installing the #4 plug in this fashion, that is, the
> 1600 engine was known to have problems keeping itself cool, especially
> in tropic climates such as Brazil, whereas there's no history of
> lubrication failures.
>
> With the HVX mods the oil cooling system is modified in that ALL of
> the oil flows throiugh a low-restriction oil cooler (ie, the Mesa-
> type). In a vehicle, the flow to the oil cooler is usually governed
> by a thermostatic valve which by-passes the oil cooler until the oil
> temperature reaches approximately 180 degrees. In an airplane, the
> temperature is controlled MANUALLY. The pilot opens or closes a set
> of shutters which controls the flow of cooling air throuigh the oil
> cooler. Using manual control is a bit old fashioned but it removes a
> component from the system (ie, the thermostatically controlled valve)
> and gives the pilot the ability to pre-configure the cooling system
> prior to take-off (ie, OIL COOLER - OPEN ). With a big engine (and
> at least a quart more oil) you've got a lot of waste heat to manage.
> Prior to take-off you can get stuck behind some guy doing his nails
> and it may be twenty minutes before you're cleared for take-off --
> plenty of time for your Oil Temp to creep into the red. Your take-off
> run will bring it down a tad but you're at full throttle and as soon
> as you begin your climb-out your oil temp will start to rise, Since
> the angle of the aircraft will reduce air-flow through the oil cooler,
> you'll want to keep your climb-out rather flat.
>
> If you're just doing Bumps & Grinds out of some cow pasture you'd
> probably have the oil cooler in the circuit all the time. But if
> you're actually going to FLY somewhere, configuring the engine for
> optimum performance at your cruising speed & altitude is critical,
> since it effects how much fuel you'll burn... which dictates how far
> you can fly. Once you are at your cruising altitude your oil temp
> will tend to be too cold. So you partially close the shutters until
> it's back in the green. Ditto for a long descent, during which the
> engine will tend to cool off.
>
> NOTE: Once you reach your cruising altitude there are a number of
> chores to do, adjusting the mixture control and oil temp to give you
> the best performance at the lowest rpm. These tasks are usually
> referred to as housekeeping. Once you've done the housekeeping, if
> you follow the 'official' airways, you can look forward to about three
> hours of boredom mixed with a few minutes of total terror, when your
> puddle-jumper is overtaken and passed by larger, heavier, faster
> airplanes, some of which think it's great fun to see how close they
> can come to your wing tip. However, with a GPS that fits in your
> shirt pocket you're no longer bound to the airways, allowing you to
> pick a route that takes advantage of the prevailing winds. But you'll
> probably do what most us puddle-jumper drivers do: simply follow the
> railroad track. :-)
> ------------------------------------------------------------------------------
>
> With vehicles you can't always count on the forward motion of the
> vehicle to provide enough air-flow through the cooler. Installing an
> auxiliary fan is the usual solution, although there are designs out
> there which utilize part of the output from the engine's blower to
> cool the oil. This is similar in concept to the stock configuration
> but on a much larger scale. (See Jake Raby's web site).
>
> -R.S.Hoover
>
> ---------------------------------------------------------------------------------------------------------------------------
>
> Bob, I am following your instructionsand learning much. I have a
> question as the longer plug to the #4 bearing is supposed to be a flow
> balancer/ restricter to the # 4 bearing so most of the oil goes to the
> crank/cam bearings. This is according to a forem on the samba. It
> appears to me that the idea has some merit. I have pulled the plug and
> tapped it according to your and several others instructions. I have
> done the HVX oiling mods, ( I am at the jugs now.) any thaughts to the
> idea? PS thanks for the help. Hope you get
> better.
>
>

Dear mr Hoover,

thank you for this info - I was wondering the same thing. It's amazing
how you keep posting great articles despite your illness

Bas

On Oct 14, 11:45*am, Bas > wrote:

> thank you for this info - I was wondering the same thing. It's amazing
> how you keep posting great articles despite your illness
>
> Bas
--------------------------------------------------------------------------------------

Dear Bas,

While Multiple Myeloma is incurable it IS treatable, meaning there's
drugs out there that can kill the myeloma tumor. If you can kill the
tumor -- or most of it -- and control the pain, you can still get
around, so some work and so on. If you're rich that's no problem --
money buys you better health -- (Geraldine Ferraro was diagnosed with
MM some years ago). But the Myeloma tumor is a trickster. Few drugs
are 100% effective and the tumor builds up a tolerance for them... and
starts growing again. So they try something else... or hit you with
more radiation or whatever.

The record shows the tumor always wins. But you CAN make an effort to
stave it off. Which is what I'm doing.

I took the trash down tonight, a major accomplishment, something I
havent been able to do in about four months. It was damned hard to do
but I did it. It will be easier next week.

As for the writing, what would you do if you had to sit on your ass
eight or ten hours a day? I don't watch TV and I've read everything
in the house. New books are too expensive and our library doesn't
carry many of the authors I enjoy, plus you gotta get there & back. I
can only stand up for about fifteen minutes at a time then the back
starts to spasm (the tumor is in my lower back & spine - go to my
blog and you can see the marks left by the x-ray). After 15min I
gotta take a pain-killer and sit down. I can only do that about four
times before the pain-killers stop working an I have to wait a couple
of hours before I can take something more powerful.

So I write. If you write, you get a lot of mail; guys asking how to
do something that I've done a zillion times. So I tell him how I did
it. Which isn't always the way it sez in the manuals... which usually
gets you some MORE mail :-)

The point here is that you shouldn't be amazed by the fact I'm still
writing. If you were unlucky enough to be afflicted with cancer I'm
sure you'd do much the same. I've got it. No sense in pretending I
don't. But there's even less sense in letting it put me down like an
old horse. And who knows Maybe they'll come up with a cure between
now and Then.

-Bob