Date: Thu, 28 Mar 2002 08:34:47 -0600
Reply-To: Stan Wilder <wilden1@JUNO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Stan Wilder <wilden1@JUNO.COM>
Subject: RX7 oil cooler info update/Audi Oil temp Sender
Content-Type: text/plain; charset=us-ascii
Here is what I've done:
#1.Audi sender in the oil bypass port. (the port with the big screwdriver
slot next to the oil filter)You'll need three copper washer spacers for
proper bypass spring tension. You'll just have to match the sender BAR to
the gauge or try to get the full set from an 87 Audi500GT Coupe or a
matched set . (copper washer from the RX 7 cooler work for spacers) I've
also used a standard VDO sender in a drilled sump plate and get 5/10 c
degerees variance in the temp readings. I suspect that the Audi readings
are higher because of the heat transfer from the engine block through the
threads. The ideal situation would to have a teflon heat isolation sleve
to fit either sender.
#2. Installed Mazda RX7 Oil cooler under my van it has a 148 degreeF
thermostat, I ran the lines with a oil filter sandwich plate (generic
item from List Vendors) 60" from sandwich plate, 1/2" lines.
The 130 c = 266 f and yes it was hot. That is why I installed the oil
cooler. I could lower the temperature in the engine by reducing load /
speed and get it to run in the 100/120 c range. I think you need at least
200 f for your oil to work properly. Any colder than this and it doesn't
bleed past your oil pressure plungers properly for the bypass process.
Remember that this is a new engine and is very tight, 80+ (6 bar +) oil
pressure on startups and for the next twenty minutes, 22-28 psi at
operating temp idling at 800-900, 45-50 at 2400 rpm, 60+ (4.5 bar) at
3300 rpm.
This engine only has 5000 miles on it and I expect it to loosten up and
run cooler in the future but I'm OK with the system the way I've got it.
I haven't gotten to our hottest days here in Texas and they start in late
June and run through August but I'm confident that the RX7 cooler will be
sufficient (might add a scoop or fan, got plenty of room).
Nienty percent of the time I can run 70 mph or 75 mph (3300-3500 rpm)and
maintain the same oil temp and cylinder head temp, it just doesn't seem
to make any difference. I'm guessing this is the optimum for the Type IV
pushing 5300 pounds. Smaller vehicles would certainly get different
readings. CHT 350/370 normal.
There are a few other things that need to be addressed and I haven't
explored them:
#1, The stock single bypass on the Type 4 2000cc engine is supposed to
bypass at 47 PSI. I haven't tested this or modified the spring tension
since I'm holding 60+ at 3000+ rpms. General consensus is to replace the
spring and plunger with a new so I'm working with a known starting value.
#2. The oil filter mount has a bypass check ball, also the sandwich plate
has an oil bypass check ball. The OEM bypass check ball is supposed to be
plugged with a freeze plug when the sandwich adapter is installed.
I have not blocked this return port. The sandwich plate check valve is
supposed to raise oil pressure so as to accomidate lower pressures when
the oil cooler is installed.
#3. The OEM Type 4 oil cooler is still in place, I'm leaving it there.
#4. It is said the the 1800 oval port heads have larger valves and they
naturally run cooler than CV engine series square port heads.
This combination of installed parts would warrant an article in a VW
publication but here in the US Vanagons and Type IV engines are seldom
addressed in the mags.
Stan Wilder
83 Air Cooled Westfalia
On Thu, 28 Mar 2002 11:48:02 +0000 "Nigel Anthony Skeet"
<naskeet@hotmail.com> writes:
> From: Nigel A. Skeet
> To: Stan Wilder
> Date: 28th March 2002
> Reply to: naskeet@hotmail.com
>
> Dear Stan.
>
> I was interested to read your July 2001 postings about the oil
> temperature
> range observed with your 1983 VW 2000 Type 2 Westfalia motorcaravan,
> under a
> variety of hot summer weather conditions in Texas, USA.
>
> I also noted your discovery that a 1987 Audi GT oil-temperature
> sender unit
> can be used to replace the standard oil by-pass plug on your
> air-cooled
> engine.
>
> Am I correct in thinking that is the large plug with screw-driver
> slot,
> which screws in underneath the bottom of the crankcase, rather than
> the
> small plug in the form of an XZN socket screw, which screws in the
> side of
> the crankcase, near the pushrod tubes?
>
> Do you by chance know any more about the origin of the
> oil-temperature
> sender (e.g. the VW-Audi part number) and whether it is compatible
> with the
> VDO Cockpit accessory 50~150 deg.C oil-temperature gauge.
>
> In the near future, I shall be fitting a 1911cc VW 17/1800 Type 2 &
> 4 hybrid
> engine (hybridised from a VW 411LE & two 1974~75 VW 1800 Type 2
> engines), to
> my 1973 VW '1600' Type 2 Westfalia Continental motorcaravan, which I
> hope to
> equip with a Swedish specification oil-sump immersion heater. Hence
> an
> alternative location for an oil-temperature sender would be rather
> useful.
>
> I have experienced ambient air temperatures, in excess of 30 deg.C,
> during
> hot summers in Europe and Great Britain, when the oil-temperature of
> our
> 1600 engine peaked at 115~120 deg.C, but from what I've heard so far
> about
> VW 17/18/2000 Type 2 & 4 engines, yours seems to be running rather
> hot.
>
> Do other listees in Texas experience noticeably lower oil
> temperatures than
> you found with your newly rebuilt engine? 130 deg.F seems rather
> high!
>
> I would be interested to learn more about the correlation between
> oil
> temperature and ambient air temperature, under different conditions
> of
> speed, engine load, gradient and altitude, etc.
>
> During the past few years, I have been trying to compile a book of
> useful
> technical tips (of type not found in workshop manuals),
> modifications,
> upgrades and improvements, pertaining to the 1968~83 VW Type 2 and
> related
> vehicles. I don't have a monopoly on good ideas or knowledge, so I
> am hoping
> to include contributions from fellow owners, plus workers in the
> automotive
> and allied trades.
>
> So far, a few of my technical articles have been published in the VW
>
> Motoring Magazine, plus the magazine and technical information
> booklets of
> the British VW Type 2 Owners Club (about 2,500 fully paid up
> members).
>
>
> You said in July 2001
>
>
> >I'm useing an 87 Audi GT sending unit that screws directly into the
> oli
> >bypass valve (replacing the stock plug) I'm showing 130 celsius or
> about
> >266 degrees faremheit.
>
> >Most list members claim to running about 240 degrees farenheit but
> >although my oil temp is reading high I don't think the oil is realy
> 266
> >hot.
>
> >My engine is new and I'd suspect that it may drop some after
> breakin.
> >The outside temperature here in Texas has been between 90 nand 100
> daily so
> >I'd expect a little hot. Around town just average driving I'm
> running 212
> >to 220, but a highway speeds it climbs on up there to 266.
> >
> >Stan Wilder
> >83 Westfalia Air cooled
>
-----------------------------
From: Nigel A. Skeet
To: Stan Wilder
Date: 28th March 2002
Reply to: naskeet@hotmail.com
Dear Stan.
I was interested to read your July 2001 postings about the oil
temperature
range observed with your 1983 VW 2000 Type 2 Westfalia motorcaravan,
under a
variety of hot summer weather conditions in Texas, USA.
I also noted your discovery that a 1987 Audi GT oil-temperature sender
unit
can be used to replace the standard oil by-pass plug on your air-cooled
engine.
Am I correct in thinking that is the large plug with screw-driver slot,
which screws in underneath the bottom of the crankcase, rather than the
small plug in the form of an XZN socket screw, which screws in the side
of
the crankcase, near the pushrod tubes?
Do you by chance know any more about the origin of the oil-temperature
sender (e.g. the VW-Audi part number) and whether it is compatible with
the
VDO Cockpit accessory 50~150 deg.C oil-temperature gauge.
In the near future, I shall be fitting a 1911cc VW 17/1800 Type 2 & 4
hybrid
engine (hybridised from a VW 411LE & two 1974~75 VW 1800 Type 2 engines),
to
my 1973 VW '1600' Type 2 Westfalia Continental motorcaravan, which I hope
to
equip with a Swedish specification oil-sump immersion heater. Hence an
alternative location for an oil-temperature sender would be rather
useful.
I have experienced ambient air temperatures, in excess of 30 deg.C,
during
hot summers in Europe and Great Britain, when the oil-temperature of our
1600 engine peaked at 115~120 deg.C, but from what I've heard so far
about
VW 17/18/2000 Type 2 & 4 engines, yours seems to be running rather hot.
Do other listees in Texas experience noticeably lower oil temperatures
than
you found with your newly rebuilt engine? 130 deg.F seems rather high!
I would be interested to learn more about the correlation between oil
temperature and ambient air temperature, under different conditions of
speed, engine load, gradient and altitude, etc.
During the past few years, I have been trying to compile a book of useful
technical tips (of type not found in workshop manuals), modifications,
upgrades and improvements, pertaining to the 1968~83 VW Type 2 and
related
vehicles. I don't have a monopoly on good ideas or knowledge, so I am
hoping
to include contributions from fellow owners, plus workers in the
automotive
and allied trades.
So far, a few of my technical articles have been published in the VW
Motoring Magazine, plus the magazine and technical information booklets
of
the British VW Type 2 Owners Club (about 2,500 fully paid up members).
You said in July 2001
>I'm useing an 87 Audi GT sending unit that screws directly into the oli
>bypass valve (replacing the stock plug) I'm showing 130 celsius or about
>266 degrees faremheit.
>Most list members claim to running about 240 degrees farenheit but
>although my oil temp is reading high I don't think the oil is realy 266
>hot.
>My engine is new and I'd suspect that it may drop some after breakin.
>The outside temperature here in Texas has been between 90 nand 100 dail
________________________________________________________________
GET INTERNET ACCESS FROM JUNO!
Juno offers FREE or PREMIUM Internet access for less!
Join Juno today! For your FREE software, visit:
http://dl.www.juno.com/get/web/.
