MGA Forum

Back from my model airplane days we used to boil nylon props I wonder if these need that? I guess it would help if you knew what material they were too. Might not apply either because a fan on a car will last longer than a prop on a model anyway. Here is a quote from a R/C page-

Boiling nylon props

Nylon gets brittle (and shrinks) when too dry, that is why Graupner and Tornado props should be boiled before first use to get the water content up where it should be. Emphasis on first use!, because boiling also reduces the stresses caused by the molding process.
Many props are made from fibre reinforced nylon, because it is so strong and resilient.
Boiling, if in doubt, is not required. Just keeping the parts in a moist cloth for 24 hours will do the trick as well.

Oh Boy!
Did I speak to soooon about my plastic Fan!

Add this one to the list. one year to the day I ordered it! Of course it was about 1 week before I installed it on the car, so that puts it less than a year in service.

11,238 miles before it broke doing high speed on the interstate ( 70mph,maybe a little more ).

Fortunately no damage to the Rad, hood, hose etc. makes a hellava noise when it goes though.

I spoke with Moss this afternoon and they said send it back for credit. I ordered a metal one for replacement. In the mean time I'll reinstall the electric fan till the new metal one arrives.

Dave

What happened with all the research Moss was doing on this?
I have one in my 1500, about 200 miles after restore.

Moss??

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Dave

These fans aren't glass fibre reinforced as they are much too flexible for that. The most likely reason for the failure is that the manufacturer changed the material. These parts are injection moulded and to aide cycle time they use a relatively easy flowing material - unfortunately the more easy flowing, the poorer the properties (in general), so you can see the temptation. Not saying it is that, but seems likely. I also fitted one on my TF.
Dave H (the other one!)

Dave.

We have been looking at the cooling fan that you sent back to us. The tips of all of the blades are damaged on the rear edge, which is really weird. You can kind of see the damage in the image you posted.
Are there any marks on the inside of the shroud indicating the tips were hitting?
I've seen cases where the blades flex forward under high speed and hit the upper or lower tank, but not a blade that is damaged on the rear side. I think Mike Vickers is in touch with you on this. Obviously it is a concern.

I initiated these plastic fans after bringing in my sample that I bought from the factory in 1984. The design and materials were to be exactly to the original specification. Over time, that may have strayed so we are doing a full analysis of the material to ensure it has not been cheapened.

Kelvin.
Moss Motors.

Dick, I am one that had the steel blade go through the raid & 1 big dent in the bonnet, back in 82. That is when I started using the plastic O/E fan only! I have 3 GTs that have over 300,000 miles on each one & have NEVER had a O/E plastic fan break. Barney, if the plastic fan hits a "thing", shroud or the Radiator IT WILL BREAK!!! plastic is the week link, it will break almost as soon as it touches something. I would not use a shroud with less than 1/2" between the fan/shroud & I run no less than 3/4" from the fan to the radiator & if I could I would make it 1" & looking at your pics. I can see you were way to close everywhere. I run 4 cyl. B engines with A/C & the C/B O/E plastic fan & rad. & my 74.5 GT with F/I & A/C with the stock V-8 rad. & I pull other MGs & a trailer with this GT that now has 648,545 miles on her. So I would like to hear of others that have had the Moss blade break without hitting something other than AIR. My 47 years of working/driving British cars & motorcycles, 2 cents worth!

Kelvin,

Thank you for looking into the mishap I had with my fan issue.

I have received the email from Mike and I am providing him with the information that he is requesting.

Yes , as stated in my initial post, the witness (contact) marks were a result of the blades coming into contact with the fan shroud.

"Full disclosure, when i installed the blade, the fan shroud was close enough to catch the tips of the blades and shave off 1/8 inch.
I didn't take the blade off of car to inspect it fully so it may contain fractures that i didn't see."

When this happened on start up i made corrections to the fan shroud by using Ty-wraps to pull the shroud away from the fan. The Ty-wraps remand in place until I removed them after the incident.

I would have loved not to have installed the shroud on my car, however the higher temps with the MGA's any additional help with cooling is a plus.

I'm not blaming the failure of the fan on design or manufacturing of the part.

Yes it did make contact with the fan shroud so this is a factor that needs to be considered during the evaluation.

The only reason I sent it back for evaluation is hopefully to determine of it was

1. Possible bad production run or
2. Operator install failure.




Dave



Edited 2 time(s). Last edit at 2016-07-29 09:54 PM by MGA1962.

I have been driving a '72 MGB for the last 42 years, have over 400,000 miles on it with only one rebuild. Seven years ago the stock steel fan threw a blade going freeway speed without any damage to the car. Although it sounded like the engine blew up. I purchased a plastic fan from Moss and have over 100,000 miles on it without any problems. I think the plastic is better because at high speed/rpm the blades flatten out a bit and lessens the power requirement to spin it. After the failures I've been reading about, I might order a new one and carry it with me just in case. But honestly, I trust the plastic ones if it doesn't contact anything while driving.
Bill

Definitely better when made from an appropriate grade of plastics material. However, the material used seven years ago may well be different to that used now (changes in that period of time are commonplace) and if they made a change, did the manufacturer carry out any relevant testing.
Dave

I received from Moss credit for the fan. I ordered a metal fan to install on my A.
I was on the fence whether to go with the plastic or steel. So I'll give the steel a try this time around.
Dave

So...did Moss ever provide any more info on this?
Seems like a year would be long enough to finish their research.
Maybe we should be talking to a "larger audience"?
Moss??

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Dave

At the BMTA convention in early March, Kelvin Dodd told me they had determined or decided the parts were made from the wrong material. Not that they were supposed to contain any fiberglass, but apparently just the wrong type of plastic. No word yet on whether they ever made new parts, but as far as I know there has never been any break in sales, so they may still be selling the same parts with the wrong material.

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Barney Gaylord - 1958 MGA with an attitude - https://MGAguru.com - barneymg@mgaguru.com - Ph: 630-946-3841
(Please email me direct, do not leave a PM on the public server).

Thanks Barney.
Sounds to me like another failure now could result in a lawsuit, or at least major big stink.
They should come clean on this with their customers...and prospective customers.
I wonder if the yellow plastic fans from other vendors come from the same place?

Dave

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Dave

Hello Folks,

I am far from owning either MGA or B - lucky Midget driver.

HAve been reading this thread and wondering why almost everyone posting has gone plastic from metal? Why replace something durable with something fragile? Besides, to me it isn´t quite sustainable replacing metal with plastic just for the sake of
1 or possibly 2 HPs.

BTW - thank you Barney for all your help when I had questions! I really appreciate your support and I am a great fan of your site, which is so informative!

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Cheers,
Wolf

Some owners look for the h.p. gain; some for greater volume of air; some because original fans getting harder to find in good shape; some to avoid the a steel fan throwing a blade or two due to metal fatigue.