Volvo Red Block OIL COOLER
Information
This information may come in handy when
working on or modifying oil cooler systems on 240s or other red block Volvos.
Here's a factory Volvo (made by Wahler)
oil cooler thermostat housing for a 240 Turbo. It's mounted between the
engine and the oil filter. This
240 thermostat housing has banjo fittings on the oil cooler IN/OUT ports. This was common
for the B21FT. On the later B230FT, the banjo fittings were
eliminated and straight fittings were threaded into the thermostat housing.
OIL FLOW DIRECTION
The oil flow direction became something I needed to know when I wanted to install
an in-line oil cooler thermostat
between the engine and oil cooler. My original 240 thermostat housing was not working well. It seemed
to be stuck in
the open position, not allowing the oil to warm up quickly and
taking many miles to reach warm temperatures.
The new IN-LINE thermostat I chose to add required a specific flow direction for "IN"
and "OUT."
Here's the flow
direction for this factory Wahler thermostat housing.
This diagram below was found in the 1981 Volvo "New
Car Features" Greenbook.
The factory 240 Turbo oil cooler, manufactured by Setrab in Sweden, was mounted
vertically on the left side of the 240 radiator. This is not the best
location for airflow, but it's certainly better than no oil cooler.
The male ports on a
stock Volvo Setrab oil cooler shown here are sized as 1/2 BSP Male (photo below showing unusual cone shape). There's more info HERE on fittings needed for this CLICK HERE.
Significant airflow/cooling improvement can be made by relocating this cooler
below the car, behind the front spoiler. It can be mounted there
horizontally like the below
image or you can angle it back a little if you want more ground clearance. The hose port thread information for this Setrab cooler is HERE.
I had
this oil cooler mounted very much like this for several years on my 240 before I decided to
upgrade to a larger Mazda RX7 oil cooler (RX7 details below).
If one Setrab oil cooler isn't enough, you could mount two in series, like Dick Prince did on his 240 Group A replica race car.
Here are more flow direction images for the early (up to 1986) and later (after 1986) B230FT oil cooler in the 740. Oil always flows into the oil filter around the OUTSIDE edges and then it flows out of the filter, back into the engine through the CENTER of the filter.
Here are some more
images of these oil pipes.
NOTE: Early (B21FT) original Volvo pipes used banjo fittings at the oil
filter/thermostat plate and later (B230FT) pipes used straight fittings threaded into the plate.
And some detail images of the later (after 1986) B230FT setups.
THREAD PITCH INFORMATION
Again, here's the Volvo 240 Turbo Wahler oil filter/thermostat
plate. The large
threaded pipe that goes through the center of the plate
uses 3/4
-16 threads. It's a common
thread size for many factory and aftermarket
oil filter adapters that may be found for a
large number of cars, typically Ford, Lincoln and Mercury. The IN/OUT cooler ports
where those banjo fitting are inserted are threaded 16mm x 1.5 Female.
If
you're
relocating your Volvo Setrab oil cooler or
changing your
old oil cooler pipes to racing style AN fittings
and hose, you can still use
the above Volvo Wahler oil filter/thermostat
sandwich plate. If you will be using -8 AN
racing hose (1/2 inch ID), you'll
need two 16mm
x 1.5 Male to -8 AN Male Adapters (same as in THIS photo above), which can be found at https://www.summitracing.com/parts/rus-670551.
I prefer using AN -8 (1/2 inch ID) hose for oil coolers. If you prefer
using larger AN -10 (5/8 inch ID) hose, then the adapters you would look
for are 16mm
x 1.5 Male to -10 AN Male Adapters. You'll also need two 16mm aluminum or brass crush washers or metal bonded sealing washers (below).
Metric aluminum crush washers are available at Pegasus Racing: https://www.pegasusautoracing.com/productselection.asp?Product=3278
<<<
If you're curious, these are metal-bonded
sealing washers. It's a metal washer with a rubber
o-ring embedded in it. It's generally used
in place of a brass or aluminum crush washer, except it has superior sealing. McMaster Carr
has them: https://www.mcmaster.com/#standard-washers/=1blhle3,
click "Sealing Washers," then "Metric High-Pressure
Metal-Bonded Sealing Washers" and choose size M16. They
can also be found at Pegasus Racing, called Stat-O-Seal Sealing
Washers:https://www.pegasusautoracing.com/productselection.asp?Product=3245. Choose the 5/8 inch size, which has an ID of 15.9 mm. Your local
hydraulic hose shop may have them too.
You can see other bonded washers I have used further belowCLICK HERE.
OIL HOSES and REMOTE FILTER KITS
The factory 240 Turbo oil hoses and rigid pipes were made to be pretty durable. They
are hard steel tubes coupled to flexible reinforced rubber hoses on the end that
connects to the oil cooler. Relocating the oil cooler will make
it difficult to use those factory lines. There are a lot of simple universal kits and parts that can be used on a 240 for a remote filter and/or oil cooler.
I have used universal kits in the past with simple 1/2 inch I.D. reinforced rubber oil hose, which will come with some universal kits. These kits will use brass barbed nipple fittings and simple worm-drive hose clamps. They work fine, but I should warn you that inexpensive rubber oil hose does tend to harden and shrink over years of heat exposure. This can cause your tight hose clamp connections to slowly loosen and then begin leaking. So it's a very good idea to check and tighten those clamps on occasion.
If you're shopping for a new aftermarket filter adapter or thermostatic plate and
need to know if it fits a Volvo oil filter, you may need to know the
diameter of the stock Volvo oil filter o-ring. It's 2.75 inches OD. If you find an adapter that's at least 2.5 inches ID, it should fit your filter. The kits I highlighted above will fit this size filter.
There
are lots of custom parts and universal kits
on-line. For kits that supposedly fit a 240 directly, it's hard to know
what you can trust and how well these parts will fit. Here's such a kit
with the thermostat plate, oil cooler and
fully assembled oil hoses that was installed by a
Volvo 240 Turbo owner and it seems to work
well.
Thread: https://forums.turbobricks.com/showthread.php?t=344235
MAZDA RX7 OIL COOLER This is the Mazda RX7 oil cooler, second
generation RX7 FC, 1986-92. It's
a popular retrofit for a Volvo because of it's large size. DIMENSIONS: Overall Length: 22.5 in. (Core length: 19.75 in.). Height: 4.5 in. Thickness: 2 in. The IN-OUT ports on this oil
cooler are threaded 18mm
x 1.5 Female. They originally used banjo fittings with brass crush washers, which
you can also use if you like. An appropriate
banjo fitting for this will use a center bolt with
thread of 18mm x
1.5. If you instead decide to install straight AN racing hose fittings, an appropriate straight
adapter fitting will have the
following thread: 18mm x 1.5 Male to -8 AN Male.
Appropriate 18mm crush washers or bonded sealing washers should be
used on these ports whether you are using AN adapters
or banjo fittings.
It has a
built in thermostat that begins opening at 140º
F and is fully open at 149º F. Those temps are too
low for a Volvo, because it can make warming up the car take a long time. So using a different thermostat
elsewhere
would be a better idea. The built-in thermostat
is inside the end-tank where the IN-OUT ports are. It can be removed if
you like and the bypass port inside is a simple hole that can be blocked with a nut and bolt as shown below.
MORE OIL RELATED THREAD PITCH INFO
Here are some of the oil related ports on a Volvo red block. B21/23FT: Turbo Oil Feed: M14x1.5.
B230FT: Turbo Oil Feed: M14x1.5.
All engines: Oil Filter Center Port: 3/4-16.
B21/23FT: Oil Pressure Sender: 1/8 NPT.
B230FT: Oil Pressure Sender: M14x1.5.
Oil
Cooler
Thermostats
The factory Volvo (Wahler) oil cooler thermostat (near the top of this page), which came in my
240 Turbo, seemed to stop
working as it should. My guess is it was maybe stuck in an open position, since it was taking forever for the
engine oil to come up to temperature. So a number of years ago I
decided to add an IN-LINE oil cooler thermostat.
At that time I was using an aftermarket universal oil filter kit and
aftermarket 1/2 inch I.D. rubber oil hoses for the oil cooler
lines.
This
is the Hayden
163 thermostat.
It's made of
aluminum and designed for use with engine
oil or transmission fluid. When cold it
bypasses the cooler, returning oil to the
engine. It begins releasing oil to the
cooler at 160°F and allows full flow at
180°F.
Fittings/Threads included: 3/8 inch NPT with 3/8 inch and
1/2 inch barbed nipples so you can choose hose size. Here are the
instructions and an explanation of how it
works: https://www.davebarton.com/pdf/Hayden163.pdf(PDF
100kb)
This thermostat
has 3/8 inch
NPT Female threaded ports. I
used one of these for a while along with 1/2 inch I.D. rubber oil hoses clamped to
barbed
fittings. A
better solution (that I eventually changed to) is racing style AN
fittings and high-performance oil hose, however
it's more expensive. The
adapters needed to use -8 AN oil hose on this
thermostat would be 3/8 inch NPT male
to -8 AN Male. Summit has some of
these for as low as $3.00 each: https://www.summitracing.com/parts/sum-220846b.
2019 HOSE UPGRADE AND NEW OIL PLUMBING PROJECT
In
2019 I decided to do a complete change with all new parts for my remote oil filter and RX7
oil cooler plumbing. I was previously using cheap rubber oil
hose that I bought years earlier from Summit Racing. It had served
well, but after years of heat it had begun shrinking and hardening and
the hose clamps were slowly loosening and causing leaks. I could have
just replaced it with new cheap oil hose from Summit, but instead I decided to
upgrade to Aeroquip Socketless hose and then document the full installation here. BETTER OIL HOSES
My suggestion, if you can afford it, isAeroquip
Socketless Hose (pictured below).
This premium hose has a rubber core and it connects to special
barbed Aeroquip Socketless hose fittings. Assembly is generally faster
and easier than other racing hose fittings. And routing hoses is easier because
these hoses are more flexible than most other racing hose, which has stainless steel braided covering.
Aeroquip Socketless is rated at 300 degrees Fahrenheit. More general info
can be found here:https://www.jegs.com/p/Aeroquip/Aeroquip-Socketless
ASSEMBLING SOCKETLESS HOSE FITTINGS This
job doesn't always go as planned. Sometimes it's a lot harder to
assembly these than it shows in videos. So here's some helpful notes below.
I
bought
one of these inexpensive assembly tools. It worked just ok sometimes. I
found was made cheaply and it was hard to grip the hose without the hose slipping.
I
found that still some hoses just refused to slide on fully as shown in that guy’s video, so then I
resorted to warming the hose to soften it. I used a heat gun, while clamping the
fitting in a vise.Don't melt the hose. Just a little heat, but enough to make the hose too hot to hold with a bare hand. So you'll need gloves to keep from
burning yourself. Here’s
one way someone used to heat which is probably better for the hose: https://www.youtube.com/watch?v=jpRwzoWuDVE
And
there are more videos in Youtube that will help. Try searching socketless hose
assembly.
OETIKER CLAMPS While no hose clamps are
technically required for the Aeroquip Socketless
hose I used, but I think it's a smart practice is to add simple Oetiker Clamps.
These are also know as Pinch Clamps orStepless Ear Clamps. I
used them in my installation and these can be seen in Aeroquip hose installation
photos in this page. These will offer a much stronger connection and
seal, just to add some extra security.These clamps may be found
at Summit Racing, Grainger or many other parts
suppliers.
Here are some
videos showing the installation of Oetiker clamps: https://www.youtube.com/watch?v=W1qTw8OmbMA https://www.youtube.com/watch?v=Xn8iv10LV5A
I needed to replace the factory Volvo (Wahler) sandwich plate with an aftermarket filter adapter plate. Plus I decided that I would install a remote oil filter under the front right corner of the car.
The long factory threaded nipple needed to be removed. It's threaded
into the block and if it's never been removed, it will be tight.
A
pipe wrench turning counter-clockwise will give you the grip and leverage you need. This oil filter adapter ABOVE is Derale Cooling Products PN 35703 from Summit Racing: https://www.summitracing.com/parts/der-35703.
The threads in the ports are AN -10 (O-ring).
The "O-ring" designation means that an there is a recess machined into the ports (seen above) for an o-ring
to be used under each of the hose fittings.
The hose fittings are Aeroquip FBM5163 (AN -10 male to -8 male adapters) and may be found here: https://www.summitracing.com/parts/aer-fbm5163. These hose fitting are considered to be reducer fittings; from AN -10 to -8. I used them because I prefer to use smaller AN -8 oil hose for a Volvo engine.
AN -8 hose has an I.D. of 1/2 inch, which is a fine size for oil hoses. The larger AN -10 hose has an I.D. of 5/8 inch. .
AN RACING HOSE SIZE TRIVIA AN racing style hose internal diameter (ID) is measured in 1/16th of an inch increments. -8 AN hose is 8/16th inch ID (or 1/2 inch). -10 AN hose is 10/16th inch ID (or 5/8 inch). It's that simple. So I'm using -8 AN hose with this project, which is 1/2 inch I.D.
The long threaded factory
Volvo nipple I removed is Volvo PN 1306707 (for B21FT). It was too long
for my use, so I needed a shorter one.
A new, shorter threaded
nipple was needed because I was removing the thick Volvo Wahler adapter
plate. This caused a bit of a headache, because the only shorter nipple I
had on hand was the 1 inch long nipple shown in the above photo. 1 inch long was TOO SHORT to get good thread engagement.
A factory Volvo short threaded nipple, Volvo PN 418440,is 1 5/8 inches long. This size was used in all Volvo 240/740 models without an oil cooler adapter plate. It appears to be NO LONGER AVAILABLE and I could not find one in that length. This is the same nipple used for all red blocks beginning with the B18 in 1961.
Nearly every 3/4-16 nipple
available on-line was either 1 inch or 1.25 inch long. So I ordered a 1.25 inch long nipple and I waited. To my pleasant surprise, it worked just fine. I was able to get 5 turns of thread engagement. The proper fitting thread is 3/4-16 (same as 3/4-16 UNF), The 1.25 inch long nipple was found here: https://www.summitracing.com/parts/trd-1034.
Aeroquip FBM5163, AN -10 male to -8 male adapter fittings shown above, found here: https://www.summitracing.com/parts/aer-fbm5163. That's heat-shrink tubing below. I've had some things vibrate
loose
before on my engine, so as a preventative measure I added some heat-shrink tubing to help
keep fittings from loosening. A simple zip-tie wrapped around both
fittings would work too, as long as it'll survive long-term heat. If you have more money to spend, a lower profile and more expensive alternative is shown from Improved Racing Products: https://www.summitracing.com/parts/irp-env-160.
Permatex thread sealant with Teflon (PTFE) was used for all threaded adapters. This is essentially what people refer to when using "liquid Teflon tape."
While routing the hoses toward the
front, there may be places where they come close or actually touch parts
of the car. If you have a way to clamp them to the frame, that would be
a good solution. Some rubber or foam insulating material, like a piece of split rubber hose or this rubber sheeting above, can be used to protect the hoses from chaffing.
MAZDA OIL COOLER Here's my RX7 oil cooler. More details about the Mazda FC oil cooler can be found HERE.
It's mounted under my car, directly below the radiator bottom cross member, in the airflow path behind the lower front spoiler opening. ORIGINALLY this oil cooler came in a 1986-92 Mazda and used BANJO fittings with brass crush washers.
SHOWN ABOVE: That's the IN port on top of the Mazda oil cooler. These
IN and OUT ports are threaded M18x1.5.
For that top IN port I
would have preferred to use an 18 mm x 1.5 to -8 AN Male Adapter with a 90 or 180 degree AN hose fitting, but
space was limited in my car above this port. So I found the shown aluminum BANJO fitting (M18x1.5) in my parts bin and decided to make it work.
It's bolted to the port using an M18 x 1.5 banjo bolt. Then I added a -8 AN Male to 3/8 inch NPT Adapter to the banjo fitting: https://www.summitracing.com/parts/aer-fbm5007 and also then the -8 AN 90 DEGREE Aeroquip Socketless hose end:https://www.summitracing.com/parts/aer-fbl1533.
I used METAL-BONDED SEALING WASHERS on each port that would normally use traditional brass crush washers.
Here's one of the metal-bonded sealing washers above along with the fitting I used in the bottom OUT port. This fitting is Russell PN 670561, 18 mm x 1.5 to -8 AN Male (or M18x1.5 to -8 AN Male): https://www.summitracing.com/parts/rus-670561.
These special sealing washers are designed for very high pressure hydraulic
hose fittings and they seal much, much better than old-school crush
washers.
Here's the RX7 oil cooler installed with hoses.
Here are the remote oil filter parts that I mounted under the front right front corner of the car, behind the bumper. This is Permacool PN 1791:https://www.summitracing.com/parts/prm-1791.This OIL FILTER MOUNT has an integrated mounting bracket.
This oil filter mount fits a normal Volvo oil filter or any similar filter using 3/4-16 threads (same as 3/4-16 UNF). The IN and OUT ports are 1/2 inch NPT thread and it came with 1/2 inch NPT threaded plugs.
This THERMOSTAT SANDWICH PLATE
above mounts directly to the above filter mount. This sandwich plate allows oil flow
through to the filter when cold, but will restrict flow out to the OIL COOLER
until it reaches about 170-180ºF temperature. When cold, the oil goes through the filter and then returns to the engine. This is Hayden PN 205:https://www.summitracing.com/parts/hda-205.The IN and OUT ports are 3/8 inch NPT thread.
Here are the above pieces assembled
using their respecting AN hose fittings. I marked the oil flow (IN-OUT)
directions in these, which can be seen in these photos. The hose fittings used on the OIL FILTER MOUNT are Aeroquip FBM5008 -8 AN to 1/2 inch NPT: https://www.summitracing.com/parts/AER-FBM5008. The hose fittings used on the THERMOSTAT PLATE are Aeroquip FBM5007 -8 AN to 3/8 inch NPT: https://www.summitracing.com/parts/AER-FBM5007.
ABOVE: Here's the remote filter mounted in place
just ahead of the front-right inner fender. I made a mounting bracket
from sheet metal. It's a very convenient place to change filters.
The 90 degree fittings on the thermostat plate are AN -8 90 degree Aeroquip Socketless hose ends:https://www.summitracing.com/parts/aer-fbl1533. The 45 degree fittings on the oil filter mount are AN -8 45 degree Aeroquip Socketless hose ends:https://www.summitracing.com/parts/aer-fbl1523.
Here's the bracket I made above. It's made using sheet steel that I trimmed with tin snips and bent in a vise. It uses three bolts to two different mounting locations under the car.
If your fabrication skills are a bit more challenged, here's an inexpensive
pre-made universal bracket made to bolt to the PermaCool filter mount.This could
probably be made to work with a little bending and drilling by you. Available at: https://www.cbperformance.com/product-p/1718.htm This photo above is peeking just under the front spoiler. The bottom of the
plumbing is about 2 inches higherthan the bottom of the front spoiler.
And here's a pic above with the belly splash pan in place. It has a few custom snips to the plastic to make the hoses fit.
The convenience of changing a filter now is much better.
I simply place a pan under and begin unscrewing the filter. I let it drain for a minute, then spin it off. Nice and neat.
Remote Oil Temp Sender
I used an oil temp sender in my oil pan drain plug for years, but a sender that low comes with risks, especially if your car is lower than stock like mine. The above oil drain plug thread is 3/4-16
(same as 3/4-16 UNF) and VDO used to make a sender like above for
Volvo. It's NLA from Volvo or from VDO, but custom ones can be made and
are occasionally made available by others. So in 2021, after destroying my second too low sender (damaged one shown above right), I decided to place a temp sender in the remote oil filter mount instead. The above remote oil filter mount is Permacool PN 1791. More detail on this mount is found above (or CLICK HERE) for my installation info. Some oil filter mounts like this have extra IN and
OUT ports. Some of these ports are threaded 3/8 inch NPT (same as
3/8-18) and some are threaded 1/2 inch NPT (same size as 1/2-14).
The ports for this Permacool part were threaded 1/2 inch NPT.
I wanted to use a VDO 150ºC (300ºF) oil temp sender I already had in my tool box. It was threaded M10x1.0. A 150ºC (300ºF) temp sender is appropriate for the Volvo 300ºF temp gauge I'm using. So I found an adapter fitting on-line to adapt an unused port in this mount to fit the M10x1.0 threaded temp sender. This adapter fitting shown above was found at Fittings Space: https://www.fittings.space/gbm2p-08zm-m10x10f or you can search for: M10x1.0 Female to 1/2” NPT Male Gauge Sensor Adapter.
VDO
temp senders can be found with many different thread choices including: 1/8-27 NPT, 1/4-18 NPT, 3/8-18 NPT, 1/2-14NPT (which
would fit the Permacool mount without an adapter), M10x1.0 (mine), M12x1.5, M14x1.5,
M16x1.5 or M18x1.5. I
think I would prefer this sender to be in the oil sump. If I had a better
reason to remove my oil pan, a threaded bung could be welded on the side
for a temp sender. But for now this configuration works
fine as long as the filter mount is properly grounded to the chassis to
provide a ground for the sender. The photo above right shows where the temp sender is in
relation to oil flow. It's getting hot oil directly from the
engine after being pressurized by the oil pump. I placed the sender in
this location because I think it would read the hottest oil available.
If the temp sender was in the other port, it would be reading oil
returning to the engine FROM THE OIL COOLER. Is it better the way I did
it? Who knows. It's just one way of doing it. It works pretty well
though.
If the above banjo bolt idea were used for an earlier style banjo bolt,
the above OUT TO COOLER bolt would be the one to modify if you want
hottest oil to be monitored.
