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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - Is 4 bladed fan original?

All of the pictures, info, and other A's I've seen seem to have a 6 bladed fan. However my roadster, built April '56, has a 4 bladed fan. Just wondering if anyone knows for sure if 4 bladed fans were used on early cars. Does anyone else have an early car with an original 4 blader? Also wondering if switching to 6 blades would significantly increase the airflow through the radiator in stop-n-go traffic?
Andy Bounsall

To the best of my knowlege the 4 blade is correct. My 58 has a yellow 4 blade.
Don
D.M. Black

According to Clausager--a six bladed fan was standard on all cars, including the TC. Early 1500's were painted black, later red Late 1600's and MkII's were yellow.
R. L Carleen

Andy, Six bladed on all three engines I have!
Al
A.T. Tirella

6 blades on all 7 cars I have owned 57,58,58,58,60,60,62
R J Brown

My 57 has 4 blades. The 62 has 6.
D.M. MacDonald

So, where did the four blade fan come from? My last MGA had a four blade fan on it too.
D.M. Black

DM

One of my spare parts magazines shows the 4-blade fan on the ZA/ZB and W5 (Wolseley 4/44 & 15/15?).

Steve
Steve Gyles

Sorry, I meant Wolseley 15/50.

Pity we can't edit our posts for typos.

Steve
Steve Gyles

Andy, my 57 coupe has a 4 bladed fan. It is a 2 part fan when I removed the bolts the fan came of in two sections two fans each.

Jones

Yes, that's what my 4 blade is like...2 pieces, each with 2 blades.
Andy Bounsall

That's how my parts book shows them for the ZA/ZB etc

Steve
Steve Gyles


Hi ,
My copy of the MGA 1600 series service parts list shows a 6-bladed fan,part no. AEG129.
There is no reference to any other fan for the 1600.

Ray.
RC Brown

So do you think the 6 bladed fan would pull much more air through the radiator at idle to help keep the temperature down in stop and go traffic?
Andy Bounsall

Since it seems that a lot of people have had the original fan (6 bladed) replaced with a four bladed fan, it would be interesting to do a poll to see if people experiencing cooling problems have the four bladed fan also. My guess is that a bent 6 bladed fan might have been replaced with whatever MG fan was on hand in these instances, especially if the parts book indicates the six bladed one as original
Al
A. Tirella

Andy,

Next time you drop by my place, let me show you the electric push fan that I added in front of the radiator on my wife's MGB. If you are concerned about overheating in bumper to bumper traffic, and don't mind the added-on look (only seen from under the bonnet), it may be the way to go for you. I hooked it up to a proper MGB heater switch that reads "FAN". You could use the unused Fog Light switch on your MGA. Food for thought...

Karl
Karl Leclerc

It almost sounds like fans from the T-series have somehow made it into some of these MGA's.

http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=32736

The T-series fans are made in two pieces, held together by four bolts that screw into the water pump pulley.

I definitely DON'T recommend using a four bladed fan - the cooling in my TC (1949, not twin cam) definitely improved when I went to the MGB plastic 6-bladed fan.

Gene


Gene Gillam

This all raises some interesting issues on propeller (fan) efficiency. My propeller aerodynamics is rather rusty now (1966 since I last drove a prop aircraft). My understanding is that for a given engine speed and thrust you can reduce the fan diameter as you inrease the number of blades.

Looking at the MGA fans, they all seem to be the same diameter (please correct me if I am wrong on this one). Therefore, at a given engine speed the 6-blade fan will provide more thrust (cooling air) than a 4-blade fan. However, you do not get something for nothing. The trade off is reduced engine performance.

My guess is that owners of cars fitted with the 4-blade fans at some stage in the car's life opted for less cooling but more engine power. i.e. they were used for racing etc.

Steve
Steve Gyles

With a house fan (overhead) they say that a 4 bladed fan will circulate more air then a 5 bladed fan will ???????? Food for thought
Jones

Karl, I've actually been thinking about doing exactly what you mentioned...but only if I really need to.

Last summer I found that when sitting in heavy traffic on HOT day, the temperature would climb up towards 210, or more. Since then I've replaced the thermostat, added a blanking sleeve, added a bottle of water-wetter to the coolant, and installed the felt seal that was missing above the radiator. So far this year, the temp seems to be holding nicely at about 170, inching up to 190 once when I was stuck in traffic. That's a definite improvement, but we haven't hit the hottest weather yet.

Im thinking of changing the 4 bladed fan for a 6 blader for two reasons. First in hopes of perhaps gaining a few less degrees of heat, and sendly because it seems that the 6 blade fan is "more correct" for the car. I didn't want to go ahead and do it only to find out later that it makes no differences in cooling ability, or worse, that the 4 bladed fan was actually "more correct" for an early car.
Andy Bounsall

Gene, it's definitely not a T series fan. The shape of the blades in those pictures are much different. The blades on my fan are the same shape as the blades on the 6 bladed MGA fan, except that thereare only 4 blades.
Andy Bounsall

I did perhaps over simplify my post by not wishing to get out of my depth with my relatively shallow depth of hands-on knowledge of aerodynamics. But you cannot simply compare a 4-bladed fan with a 6-bladed fan unless you take into account the aerodynamic profile, diameter and pitch of each blade. Sure, with modern day research techniques there are undoubtedly 4-bladed fans that are more efficient than 6.

Do not forget, however, we are talking late 1940s, early 50s technology when scientists were still wondering why straight wing aerofoil sections would not go supersonic without total loss of control.

I have not measured MG 4-bladed pitch angles, chord and diameter, nor 6-bladed, but my bet is that they are very similar.

Steve
Steve Gyles

Steve, I spoke with a friend who works with forklifts, they found the early lifts with four bladed fans where more efficient in moving air then the newer fan.I do agree with you on your statement on 1940/50 technology. I have wondered about this but never posted any thing on it here.

Andy, if you make the change let us know if you see a +/- in temp.
Jones

Could it be a Spridget Fan blade?

http://mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=29278
Chuck Schaefer

Oops, a mistake on my part. I should of looked first. Its a 6 bladed fan. My last "A" had a four. My TD had a four, and so did my midget.
D.M. Black

Nope. It's not a Spridget fan. It looks the same same as an A fan - center section with the curved blades riveted on - except that it's two sections, with 2 blades on each section. Haven't seen a picture of the Magnette fan. Maybe that's what it's from??

Anyhow, I'm going to replaceit with a proper 'A' 6 bladed fan. I'll report back later to let y'all know if it makes any noticable difference.
Andy Bounsall

Andy

As I indicated earlier the 2-piece four-bladed fan is for the MG ZA/ZB and Wolseley 15/50. It is illustrated in NTG's catalogue exactly as you describe. The 6-bladed fan was an option for the Z series and the Wolseley.
Steve Gyles

The 4 and 6 blade fans are shown on page 10 of the following document:

http://www.ntgservices.co.uk/tempy/mga/MGA16-01.PDF

Steve
Steve Gyles

Steve, That one looks like it, much wider then the 6 bladed one.
Jones

Yes, that's it for sure. Thanks Steve.
Andy Bounsall

This thread was discussed between 07/06/2006 and 13/06/2006

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