View Full Version : Volvo's That Run Chapter 18 Radiator, Hoses, Fan and Heater Hoses

01-16-2012, 09:55 PM
Chapter 18: Radiator, Hoses, Fan and Heater Hoses

The Diesel radiator is larger than the 4 cylinder version and is reported to be adequate for the V8 cooling in all the discussions, in fact, recommended as the best, low cost solution. With the modifications to the shroud, discussed below, I installed the radiator in its original position with its original support and fastenings. The radiator hose fittings are 1.25” and the Ford water pump input (top) is 1.5”, the bottom is 1.75”. I easily found a formed hose that fit the upper requirements hanging on the rack at the local auto parts store. The lower hose was just about as easy but I had to add an ‘adapter’ to the radiator nipple to convert it from 1.25” to 1.5”. That adapter was simply a two inch piece of the surplus upper hose length. Adapters are made to change sizes in 0.25” increments but I would suggest that one size adjustment might be all that is wise. For this specific application the part numbers are: upper - Advance part number 71133, lower - O’Riley part number 20923


Upper Radiator Hose


Lower Radiator Hose

Cooling Fan - or - Do as I say, not as I did.

Install an electric fan from a Taurus or order an aftermarket fan from Summit Racing that is the correct width to fit the radiator you are using. You will need to use the fan relay in the Ford Battery Junction Box or an external fan relay.

But I didn’t do that since I had ‘everything’ associated with the Explorer engine. There sat a fully functional viscous clutch fan and the Explorer fan shroud. The Explorer accessory mounting brackets and serpentine belt drive provides ample room in front of the engine to use the mechanical fan. This is in contrast to the many earlier Mustang conversions where the front accessory drives make a mechanical fan impossible and an electrical fan a tight fit. On the Explorer engine the issue to resolve is the fan shroud. The Ford shroud is about an inch too wide to fit the Volvo radiator and the front radiator cross member support is about 5 inches too high to allow the lower portion of the shroud to cover the lower 3 inches of the fan. Other than that it is a perfect fit.


Lower Radiator Shroud Modification


Cut Off Piece of Lower Shroud


Radiator Cross Member Marked For Cutoff

First, I cut approximately the bottom 5 inches off the Ford shroud. I say ‘approximately’ because that is dependent on your engine mounting position and a half inch is important. Then my personal local trailer manufacturing shop made me a 14 gauge steel bracket ($20) the size of the cut off piece plus an 1” bend across the top for bolting to the radiator cross member. ‘Bolting to the cross member’ turned out to be more difficult than originally envisioned. First, the center section of the cross member was too close to the fan to suite me and I ‘relieved’ it about a quarter inch across the 10” or so that the lower portion of the fan passed by. An air driven cut-off tool got that done in a couple minutes.

Then I realized that the bottom of the cross member was not flat. I made a cardboard pattern of the several non-flat sections of the member and transferred that to the bracket. Grinding, filing, priming, painting and it was done but I had centered the bracket on the fan. (Order the electric fan) The Ford shroud is not centered so I did all the above again moving the bracket to the left to center the shroud on the fan. Now it fit but the remaining top section of the shroud was an inch too wide to fit the radiator. (Order the electric fan).

Not to be deterred by the impossible I cut an inch out of the center of the top section of the shroud and glued and pop riveted the pieces back together to match the width of the radiator. Then I cut the top section of the Volvo shroud off and added it to the Ford shroud so the assembly would look and attach the same as the original installation. (Order the electric fan)


Center Inch of the Shroud Removed

http://i772.photobucket.com/albums/yy4/tporterellijaycom/245RadiatorShroudOriginalVolvotopconnectionpiece.j pg

Volvo Shroud Top Connection Piece



Completed Installation

Getting tired yet? Order the electric fan!

By the way, the plastic used in the fan shrouds contains a lot of silicone making the use of most adhesives a waste of time. I tried ABS cement, construction adhesive, JB Weld, Plastic Epoxy, super strong double backed tape, super glue, and a couple others and nothing would stick to the stuff. Ended up using white, double backed foam tape to hold the pieces together long enough to drill and install aluminum pop rivets.

Do as I say: install the electric fan.

Heater hoses

The heater hoses are very close to the rear of the engine and any cleanup of the firewall connectors is best done before the engine is installed. All the other hose work should be done before the intake manifold is reinstalled just for easy access. I used 90 degree 5/8” preformed elbows found hanging on the hose rack in the back of an Advance Auto Parts store then connected standard heater hose with plastic hose splicers. The engine end uses preformed ‘U’ hoses also found on the hose rack. Both the elbows and the ‘U’ hoses will need to be cut to workable lengths. Nothing difficult, you just need to be a little artistic to get everything to fit.


Firewall Heater Hose Connections


90 Degree Heater Hose and Splices


Upper 'U' Connection to Engine

The parent document of this thread can be found here: http://forums.turbobricks.com/showthread.php?t=250257

01-17-2012, 10:54 AM
i had a terribly hard time finding a new 240 diesel radiator, i looked for days and was willing to pay upwards of $400 for one but just couldn't source it. did you have a place where you located one or is it used?

i had to adapt an 850 radiator in the end because i couldn't find the diesel one.

01-17-2012, 12:50 PM
The diesel radiator came attached to the Diesel car back in '82. It worked fine when the engine quit in '95 after 180k miles but I guess you could say it was used.

If you have information about other radiators that fit developed in your search sharing them here would be helpful to others doing the conversion. Also, comments on what you had to do to the 850 would be great.

The intent of this big document is to end up with corrections, comments, new ideas to make the conversion easier to the next group of folks doing it.


01-17-2012, 08:57 PM
Don't use the plastic heater hose connections - please take my word for it. Go get the metal ones.

01-17-2012, 09:06 PM
Thanks, I looked for something other than the water hose connectors but did not ask at NAPA. I agree that metal would be better.

01-17-2012, 09:08 PM
Thanks, I looked for something other than the water hose connectors but did not ask at NAPA. I agree that metal would be better.

Advance stocks metal ones. I used a straight, and a step-down one for the heater hose connections in my car, since the LS uses 2 different sized heater hoses (AFTER I had the plastic ones burst and fail on me).

01-18-2012, 08:01 PM
Yeah, Advance has got them. Went by to purchase. $5 each x 4. Still looking.

[edit] Three years later while redoing the mechanical fan to electrical I changed out the plastic connectors to metal and put in new hoses and new screw clamps. I agree, a plastic garden hose connector failure would put you on the side of the road and get you a ride in the cab of a big flatbed truck.

01-19-2012, 01:33 PM
My radiator is from a 940 Turbo but I have concerns about it working for a V8. Ross says it will work. I'm not banking on it. For now its worth the price just to get it running.
I'll report back on that. (dont hold your breath,might be awhile:roll:)

01-19-2012, 08:56 PM
The stock radiator is plenty of radiator, it's HUGE.

01-21-2012, 12:25 PM
940 radiator will work well, 240 and 85-91 740 radiator won't keep up.

02-27-2012, 08:19 PM
After exhaustive research into adhesives for attaching PE polyethylene plastics associated with this project I determined that it couldn't be done . . . except for a couple possible solutions.

3M 'had' a product that claimed to be able to bond the PE plastic found in things like fuel tanks, radiator shrouds and windshield washer fluid bottles . . . DP8005 which appears to be no longer available.

TAP Plastics has an adhesive that claims to do the same.


I am going to give them a try.

The parent document of this thread can be found here: http://forums.turbobricks.com/showthread.php?t=250257

M.H. Yount
03-21-2012, 10:55 PM
I think radiator size has to be looked at with regard to heat rejection needs. And that's pretty much a function of operating temps, use of the vehicle and engine output. If you're also cooling an auto tranny that needs to be factored in. One that's road raced regularly is a different animal from a street car with a/c slugging through stop and go in Houston in August. Drag racing and autocrossing have different needs as well. And of course, it's not just radiator size -- but airflow across the rad and cooling fan selection/control that need to be thought through.

For what it's worth on a 325Hp 5.0L with manual tranny I used a diesel radiator and had the core replace with a 3-row 16 fin/inch contemporary core. I had it offset to the FRONT of the housing/tanks to make as much room as possible for electric fans. Set-up has been in the car for 10 years and it keeps things as cool as a cucumber. Have never run the car at a road course where it's asked to manage thermal needs at w.o.t. for long periods of time. Perhaps a beta test is required...but bigger front brakes first!

08-14-2013, 02:16 PM

More info for the G.A.N.

01-25-2015, 10:55 AM
Now that you have read all the previous posts I hope you took my advice and installed an electric fan. I just did . . . for several reasons other than my issues with the original mechanical fan installation.

First, I was getting some vibration from the mechanical clutch/fan that showed up at around 2,000 rpm as sorta a harmonic vibration. Sorta like a tire out of balance only at 65 mph.

Second, the temperature gauge occasionally would creep up and then down for no obvious reason. During this problem resolution the use of an OBDII to Bluetooth converter and the TORQUE app on an Android phone demonstrated that the PCM sensor and the gauge sensor were both failing. Simple replacement of the Ford temperature sensors fixed that . . . almost. The gauge still drifted around more than seemed normal.

Research on electric fans indicated the Taurus fan was the simple solution but I found an 11" duel SPAL fan that exactly fitted the 16" x 24" Volvo Diesel radiator and was highly rated by its users. It also claims to be the most powerful on the market. https://webstore.spalusa.com/en-us/product/0118/products/fans/30102052/2va06-ap70-ll-37a-11-p-12v-dual.aspx Don't be turned off by the manufacturer's suggested retail price. It is available at internet prices under a $100 which is not much more than you are going to pay for a junk yard used Taurus fan.


Since the fan shroud is exactly the same dimensions as the radiator frame/tanks mounting it was pretty simple. I mounted a piece of aluminum hardware store angle to the frame at the top and bottom and then added a piece of split vacuum hose to the sides of the shroud.


Fit back in fine and provided even more clearance than the mechanical fan and shroud.


The problem with these high starting current fans is the high starting current. They can put a 50 amp or more spike on the electrical system when turned on.

That concern led to research on fan controllers. Most are simple relay controls that step one fan on and then the other if the temperature does not come down. While this reduces the high current spikes they are not eliminated. What I did find was a solid state current controller from DCControls http://www.dccontrol.com/constant_temperature_controllers.htm that continuously manages the fans' speed from minimum to maximum. This device quickly and simply manages the cooling system without relays and the associated current issues. It has been in use for 10 years or more and is still highly praised. One thing, DCControls is a small company and assembles the units upon order so you should expect a couple weeks before receiving.


After all this I still had a problem. The fan controller operates but does not seem to adequately manage the engine temperature. After several email communications with Brian Baskin, the product designer and owner of DCControls we came to the conclusion that maybe the 32 year old radiator had a problem.

Now, repair it or replace it? I didn't find any radiators that that easily replaced the original one and decided to seek repair. The move to plastic tanks and aluminum cooling cores has put most of the old time shops out of business. When I was growing up, a long time ago, every small town had a local one man shop and now the local NAPA store couldn't even refer me to someone still around. I did find one, probably the last one, in North Georgia and took him the precious old radiator. Hope the EPA never finds this one last shop.


It had a very big problem. The horizontal core tubes were mostly clogged up.


. . . and when we pulled the right hand tank off we found the bottom third clogged up with junk to the point that there was little if any flow across that part of the radiator. That area was where the fan controller sensor was located and a very good reason that nothing worked as it should.

Everything back together and fully functions as expected.

The parent document of this thread can be found here: http://forums.turbobricks.com/showthread.php?t=250257

02-28-2015, 09:35 PM
While I do not live in Boston the North Georgia Mountains have seen their share of snow, ice and cold, but above zero temperatures. Today it got above 50* and I finished the controller install. Other than B+ and ground there is input from the sensor mounted in the radiator and the connection to the AC compressor.

The design being that if the AC compressor is on there should be air flowing across the AC condenser. If you have never been under the hood of a car when the AC high pressure blow off valve blows that is something you will never forget.

The schematic from DCControls indicates that a connection should be made between the compressor clutch switched B+ and the controller. My problem was that the clutch connection was on the left side and the controller was on the right side. That meant running a wire from the compressor, out to the front of the radiator and across to the controller.

Then I had a flash of adequacy . . .

There is a pressure switch on top of the accumulator/dryer that protects the system from under/over pressure issues located 18 inches from my controller mounting. My first thought was that the switch contacts would be too close to ground to report compressor operation to the controller. That didn't turn out to be true. When operating, the AC clutch voltage at the pressure switch was enough to operate the DDController.

Another problem solved.

The parent document of this thread can be found here: http://forums.turbobricks.com/showthread.php?t=250257