MGA Cooling Fan Shroud

MGA Cooling Fan Shroud

VOL 22/NUMBER 2

The MGA cooling fan shroud is designed and built by Dan Beha of Akron, Ohio. Dan spent a lot of time perfecting the design, but the end result is very simple and apparently very effective. The installation on my MGA took less than 30 minutes.

The accompanying photographs shows that the shroud comes in two halves for easy installation. To attach them on the car, they are sandwiched between the radiator and its mounting, and secured by the six bolts that hold the radiator in place. The upper and lower holes of each half are slotted so that only the center radiator mounting bolt on each side needs to be removed, while the upper and lower bolts are merely loosened.

The initial step of the installation is to loosen the upper and lower bolts on each side of the radiator, and to remove the center bolts. The radiator can then be carefully pushed or pried forward to create a gap between the radiator and its mounting. The shroud is installed in this gap. There should already be a fiber packing piece between the radiator and its mounting, and it would probably be preferable to create the gap to mount the shroud between the packing piece and the radiator. In my case, the packing piece stuck to the radiator flange and I did not think that I could separate it without destroying it. So I installed my shroud between the packing and the body flange.

The half that is installed on the right side of the car is installed first, and is the most tricky because of the location of the top radiator hose and the generator. By following the directions and with a little jiggling and patience, it can be maneuvered into place. This is accomplished by inserting it upside down on the left side, and rotating it around the fan so that it comes up on the right side the right way up. There are a few sharp edges on both the shroud and the car, so a pair of gloves might preclude a few skinned knuckles and minor cuts.

Once the right side is in place, the middle radiator bolt can be installed loosely to keep it there. The left side is a little easier to install as there is not much in the way. When both sides are in place, all six bolts can be tightened. Make sure that the shroud is centered around the fan and snug against the radiator mount at both sides.

The photographs show, as best I could, the completed installation. The whole thing is so unobtrusive that it was difficult to photograph it in place. The shroud halves are made from galvanized sheet metal, and should be painted (black) before installation. I left mine unpainted so that it would show up in the photograph, but it did not help much.

Well, so much for the installation, but is it effective? Unfortunately, with winter coming on, I did not have the driving weather to do a meaningful before and after comparison. However, Dan Beha provided the following write-up of his experience while validating the effectiveness of his design.

Shroud installed-hardly noticeable when painted black
Shroud installed-hardly noticeable when painted black
“Hot weather arrives. The outside temperature is about 94 degrees. I was working in the garage, which is even hotter, and the shroud is off. The car is running at idle, and becomes dangerously hot in about 15 minutes. I shut it off. Quickly I installed the shroud and started the car. After 30 minutes at idle, the car showed no sign of overheating and was running just above the normal operating temperatures. On the road the car showed some interesting things. At 50 mph and less, with the shroud installed, the car ran much cooler. The interior of the car was not hot. At highway speeds of 60 mph and above, I don’t think it makes much difference whether the shroud is on or off. The reason for this, I think, is the “ram-air” due to the higher rate of speed. At lower speeds, and at idle, a shroud installed around a fan makes the fan more efficient by moving air through the radiator. Without the shroud, a lot of the air that the fan is moving is the air that is already in the engine compartment, which reduces engine cooling”.

Dan’s experience is what I would have expected. The shroud should have the most noticeable effect when the engine is idling, or the car is moving slowly just the conditions one experiences when in traffic. Under these conditions, the engine cooling is relying entirely on the amount of air the fan can pull through the radiator. The shroud improves this process by ensuring that the air pulled by the fan is drawn through the entire surface area of the radiator. The shroud provides a ducting effect, which improves the efficiency of the fan operation. At higher speeds, however, the speed of the car actually pushes the air through the radiator at a faster rate than the fan can pull it. Therefore, the shroud and fan contribute nothing additional to the cooling process. If your MGA is prone to overheating on the open highway, then the shroud will not help. If it is prone to overheating in downtown traffic on a hot summer’s afternoon, then the shroud should make both you and your engine more comfortable. If you think you or your car can benefit from one of Dan’s fan shrouds he is selling them through Medina Motorsports, Inc., of Medina, Ohio. They can be contacted at 800 700-7057, or 330 225-8026. The cost is about $40.00, plus shipping (and now available from Moss).

22 thoughts on “MGA Cooling Fan Shroud”

  1. Comment by: Gilbert Clark DuPre, Jr

    By the way the fan shroud helped with the cooling, also repaired the temp gage. Runs abotu 190 in 100 deg weather here in TN

  3. Comment by: Gilbert Clark DuPre, Jr

    I installed some foam inuslation with a R10 value under the shelf and behinde the firewall. Also some insulation and sound deadner under the floor mats. Also an aluminum plate under the drivers seat. I have a roadster and its still hot in the summer but toasty in the winter with no heater. LOL

  4. Comment by: Robert L Stahlman

    Thanks Peter, I have a roadster, I am at the point where the wire and wind shield are next, I’ll order the under dash pad and do something about exhaust and floor, thanks again for the information.

  5. Comment by: Peter & Anne Tilbury

    Hi Bob,
    You don’t say if your A is a roadster or a coupe. The under dash pad was standard on the coupe and mine now has it, but many have installed it on their roadster as it really works to keep engine heat away from the interior.
    You should also think about a shield between the exhaust and the underside of the floorboards. I fitted an aluminum sheet to the footwell and under the driver’s seat on both my roadster and my coupe.
    On my coupe I also fitted heatshield material (B-Quiet) under the dash, under the roof, over the floor and tunnel, on the firewall, and under all the floor boards.
    Every bit helps!
    Peter.

  6. Comment by: Robert L Stahlman

    I am in the finale stages of a full restoration on my A , is it worth the money to put in the under dash thermal pad that Moss offers or will insulating the floor and tunnel be enough to keep the heat down in the car ?

  7. Comment by: Richard L. Colwell

    Since 1994 my trans tunnel has not doubled as a space heater.
    I was lucky enough in my past job to get to know an engineer who worked the cryogenic systems at NASA, and was awarded with a couple of yards of ceramic insulating paper (3mm thick). While it took awhile to find adhesives that stick to it, steel and carpet, it has worked well. The heat that i can no longer bear is coming from the firewall. It wasn’t so bad in Michigan or Pennsylvania, but is more noticable in southern Texas. I am toying with the idea off removing all but the wiring harness, and installing one of those thermal blankets.

    I am presently restoring a TD, and will use a high temp insulating paint on the underside as a first step there. We shall see.

  9. Comment by: Bernard Nascimento

    Rich check to see if your car has carpet under padding .When I restored my car I opted to go without under padding ,I could not rest my leg against the trans cover after 1 hour driving .I installed under padding on the floors, trans tunnel &toe; board. I could now drive long distances & rest my leg against the tunnel .Hugh reduction in passenger compartment temp.

  10. Comment by: Richard L. Colwell

    I too installed both the MOSS shroud, and the electric fan option.
    I have since removed the electric fan, as it was no longer needed. The shroud does the job. Another improvement was the addition of “water wetter” to the cooling fluid inventory. As an independant variable, by itself it was worth 3-5 degrees F.

    No if i could only cool the passenger compartment.

    rich

  11. Comment by: Bernard Nascimento

    I installed the fibre glass shroud and the Stainlees steel mesh grill.Engine temp runs between 160 to 190 city & highway .What a releif to be able to cruise and not worry about overheating.
    Bernie.

  12. Comment by: Gilbert Clark DuPre, Jr

    Thanks Mike. I have a Moss shroud on my MGB and I may put one on the A. I was thinking maybe this one was maybe made of alum. or stainelss and would be prettier. LOL

  13. Comment by: Mike Ash

    The information contained in this article is from the NAMGAR Tech Sessions and, although still valid, the information on the shroud is quite old. Back whem the article was written, Medina Motorsports had developed the shroud and fabricated it from galvanized sheet metal, and It worked very well. Since then, Moss and others have been selling a plastic shroud that should work just as well on the MGA. I bought one for my MGB.

    Mike Ash, Technical Editor

  16. Comment by: Don Wallenius

    These cars have a mechanical advance that may or may not work. It should advance to 30 degrees before tdc at 3000 rpm , if it does not the car will run hot when at highway speeds even though the timing is correct at idle. Llate timing will cause overheating and too early will cause to kick back when starting. Tks Don

  18. Comment by: John Pritchett

    How much does retarding timing or advancing do for temp and how far is too much, and has anyone used just water and did it help?

  19. Comment by: Paul M. Hornsby

    I installed a shroud from Moss Motors several years ago. It does a good job here in Louisiana. It is made of some kind of plastic..

  20. Comment by: Charles Gawthrop

    Just talked to John at Medina Motorsports. He said that Dan Beha passed away suddenly late last year. They have received a handful of requests for this shroud and they are looking at fabricating it themselves, but not sure what the price will be. Said he would get back to me in “a few weeks”. I’ll try to remember to post something when I hear back.

  21. Comment by: Morris Sulatyski

    Okay….I just posted a comment on how I wanted to buy the fan shroud and how I hoped it worked well. I only wish now is that I hoped the telephone numbers that appeared at the bottom of the artile worked well! Neither did..

  22. Comment by: Morris Sulatyski

    This sounds great! Anything to help on those hot summer days when you are stuck in heavy traffic in downtown Saskatoon! Watching the temperature gauge rise is not relaxing . I’m ordering one. Hope it works well.