sheared off engine fan blade

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mixtboy
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sheared off engine fan blade

Postby mixtboy » Sun Oct 09, 2011 9:03 pm

i was driving home yesterday and i heard a horrible clang from the engine compartment... then my gearbox seemed to go funny as well. i was doing about 55mph and obviously i immediately took my foot off the gas and coasted to a stop on the hard shoulder. turned the engine off and opened the bonnet. couldn't see any problems in there... didn't smell too bad or anything. had a walk around the van and looked underneath and couldn't see anything wrong or hangin' off. turned the engine back on, revved it a bit... sounded a bit odd... but kept running. when i started to drive off through the gears it was ok but sluggish... then it managed to get back up to about 40mph in top, but the gear stick was rattling around in fourth in a strange way. i limped the 10 miles home. when i got home, i checked the engine again and this time i noticed that the fan blade had sheared off and lodged itself in a corner. the engine still wasn't too hot.

what could cause the blade to snap? there wasn't anything else in the engine area that looked like the culprit. and what was with the transmission issue?!?!?! so confused. only just got through its MOT on saturday!!!!

help.

chrisryder
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Re: sheared off engine fan blade

Postby chrisryder » Sun Oct 09, 2011 9:12 pm

fan blades flex, like the wings on an airplane if you've ever looked out the window on a flight.

over time they can fatigue and crack, and eventually fail completely.

have both halves gone, or just one side? if it's just one then it'll be out of balance and that could be manifesting itselfs as your rough running, as it'll be shaking the engine and gearbox about.

if you replace the blade, and run it briefly, you may find it's all sorted.

linearaudio

Re: sheared off engine fan blade

Postby linearaudio » Sun Oct 09, 2011 9:16 pm

If only one of the blades has sheared off, then the horrible out of balance situation which would have occured will account for juddery shaky engine/gearlever etc. I hate to think what may have happened if it had come off while the MOT man had his head under the bonnet at the time :(
For the moment, undo the 4 fan fixing screws, remove the remains of the fan, and put the screws back in. If your cooling system is anything like mine, it will run quite happily all through winter with no fan! However, it would be sensible to replace it as soon as possible.

mixtboy
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Re: sheared off engine fan blade

Postby mixtboy » Sun Oct 09, 2011 10:56 pm

thanks for the advice... do you think i could replace it with 2 new blades... so that i create a 4 bladed fan? any benefit? i've read it cools better... but then perhaps it is overkill on my '69 ex BT van!!!

it was just one side of the 2 bladed fan that sheared off... the other one is still attached. i'll remove it tomorrow.
thanks!

mmjosh
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Re: sheared off engine fan blade

Postby mmjosh » Sun Oct 09, 2011 11:05 pm

i have 2 blades fitted on mine


bmcecosse
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Re: sheared off engine fan blade

Postby bmcecosse » Sun Oct 09, 2011 11:14 pm

You won't need any blades over winter - and for any normal summer -the single blade is plenty.
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SGTBILKO
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Re: sheared off engine fan blade

Postby SGTBILKO » Mon Oct 10, 2011 10:48 am

I had it happen years ago on a sidevalve Ford, never heard of it before. The worst was that I was driving someone who was in a hurry (!) and who insisted on carrying on. We didn't get far and I ended up having to replace the radiator!

faversham999
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Re: sheared off engine fan blade

Postby faversham999 » Mon Oct 10, 2011 2:21 pm

If you fit 2 blades you will use more petrol they are not needed in UK take it off alltogether in the winter save fuel


Neil MG
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Re: sheared off engine fan blade

Postby Neil MG » Mon Oct 10, 2011 2:30 pm

As BMC says you can remove the remaining part and run the car until the replacement comes without any problems. Standing in traffic for long periods is the only risk. When you are moving all will be fine. The MOT man is safe unless he seriously revs the engine, which he doesn't need to do!

Exactly the same thing happened to me and when I had a close look the blade had obviously been cracked for some time. Also we checked another cub members car (while he was changing the timing chain cover) and found his fan was badly cracked too. He ran without that quite happily until getting round to replacing it.

Might be worth checking your fans guys!
1956 Morris Minor Series II
1959 MGA 1600 Roadster
1966 Jaguar Mk2 3.8 MOD

DaisyMayFozz
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Re: sheared off engine fan blade

Postby DaisyMayFozz » Mon Oct 10, 2011 9:09 pm

I have 2, it provides adequate cooling and as i don't use the car much in the winter it doesn't really matter. I never noticed a difference in fuel. you can get the blades form ESM brand new for about a fiver.

Roni
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Re: sheared off engine fan blade

Postby Roni » Mon Oct 10, 2011 9:26 pm

I had the same thing happen some years ago after a deep water crossing. The blade bent a bit so it was straightened and put back on. Stresses in the hub area caused it to snap a blade off, with much clattering. It was really obvious what had happened as the departing blade sliced the bottom brass hose connection off the bottom of the radiator.


fussyoldfart
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Re: sheared off engine fan blade

Postby fussyoldfart » Mon Oct 10, 2011 10:59 pm

I used to remove the fan blades from my Minors (several of them over time) because the car became so much quieter. I ran that way all the time and had no problems. Admittedly if stuck, idling, in heavy traffic overheating is likely but as long as the car is moving at any speed above 25 or 30 MPH and not required to idle more than five minutes it should be fine. Oh! none of those cars was a 1098, Maggie is the first of those I have owned.
Fussyoldfart in Welland Ontario.


IaininTenbury
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Re: sheared off engine fan blade

Postby IaininTenbury » Tue Oct 11, 2011 2:23 am

I've had one or two break over the years - the first one at very high speed - one half of the blade ended up wedged between the HT leads on the distributor cap the other took a bite out of the rad and hit the front crossmember hard enough to cut the metal after slicing through the wiring loom. Worryingly close to the brake pipe.... :o
More recently and at sensible speeds I lost just half a blade - almighty bang lots of vibration and a headlamp went out! Limped home and took the remaining blade off the following day, and reconnected the headlight...
Last one that went, I just unbolted the remaining blade at the roadside and carried on. That one had been assembled without the square reinforcing plate with the four holes and no spring washers either, so it came loose and then stress cracked around the holes. Worth checking that the square plate is still present and that you have spring washers under the bolt heads.
cheers
Iain
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'49 MM, '53 convertible, '55 van, and a '64 van.

Marina p.u., '56 Morris Isis Traveller, a '59 Morris JB van, a'66 J4 van, a '54 Land Rover, Land Rover 130, Renault 5, '36Railton, '35 Hudson, a Mk1 Transit and a Sherpa Camper...

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mixtboy
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Re: sheared off engine fan blade

Postby mixtboy » Sun Oct 16, 2011 12:41 pm

ok so i have now replaced the blade and today took it for a run. seems to drive fine, run fine... however... now the fan assembly makes a terrible racket, rattling away at idle. there appears to be a tiny bit of play in the fan assembly where the fan is bolted with the four bolts to the spinning bit.i'd say maybe a millimetre of wobble if you use your hand to move it with the engine off. would tightening up the fan belt get rid of the noise? the fan appears to "flap" a little while running so looks slightly loose to me... also, can rotate the fan easily without the belt moving... it slips under hand pressure.

otherwise, what can i do to get rid of the racket?!!?!? i don't really want to run without a fan.

bmcecosse
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Re: sheared off engine fan blade

Postby bmcecosse » Sun Oct 16, 2011 12:43 pm

Water pump bearings are loose - perhaps damaged by (or the cause of) the snapped fan. New water pump required......
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mixtboy
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Re: sheared off engine fan blade

Postby mixtboy » Sun Oct 16, 2011 1:03 pm

is that something relatively easy to replace myself? i've only just got it back from the damn garage!!!! btw, the sound goes away as soon as some revs are put into the engine... depress the accelerator a little and the sound disappears. will driving it for a while in its current state cause any harm (other than to other people's eardrums)?

bmcecosse
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Re: sheared off engine fan blade

Postby bmcecosse » Sun Oct 16, 2011 1:10 pm

What did the 'garage' do to the car? Fan blade was most probably damaged/strained by someone pulling the engine over using the blade.. If the bearings are loose - best renew the pump asap as it could fly apart sending the fan through the rad -and dumping all the water.... It's only 4 bolts and two hoses.
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fussyoldfart
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Re: sheared off engine fan blade

Postby fussyoldfart » Sun Oct 16, 2011 7:38 pm

mixtboy wrote:ok so i have now replaced the blade and today took it for a run. seems to drive fine, run fine... however... now the fan assembly makes a terrible racket, rattling away at idle. there appears to be a tiny bit of play in the fan assembly where the fan is bolted with the four bolts to the spinning bit.i'd say maybe a millimetre of wobble if you use your hand to move it with the engine off. would tightening up the fan belt get rid of the noise? the fan appears to "flap" a little while running so looks slightly loose to me... also, can rotate the fan easily without the belt moving... it slips under hand pressure.

otherwise, what can i do to get rid of the racket?!!?!? i don't really want to run without a fan.
If the four fan bolts are loose the pulley will also be loose on the pump. Is that what you are seeing? If the 4 bots are tight and the pulley is still moveable (other than normal rotation) then the problem is almost certainly in the pump and a lot more trouble will result if you just "press on". Tightening the fan belt will only put more stress on the pump bearings, the belt needs only to be tight enough to turn the fan and the dynamo. Quoting from the shop manual:
"A gentle hand pull only must be exerted on the dynamo or the belt tension will be excessive and undue strain thrown on the dynamo bearings." Further - "When the tension is correct, it should be possible to move the belt from side to side to the extent of 1 inch (2.5 cm) at the centre of the belt run."
Over-tightened belts have probably caused many more problems than slightly loose ones.
Fussyoldfart in Welland Ontario.


bmcecosse
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Re: sheared off engine fan blade

Postby bmcecosse » Sun Oct 16, 2011 8:19 pm

That is a good point - with the fan, is the strengthening plate there too - and some washers under the head of the bolts?? As suggested - it's maybe possible that the bolts have come to end of thread - before trapping the fan assembly firmly to the waterpump.
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washer-bottle
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Re: Sheared off engine fan blade

Postby washer-bottle » Sun Dec 11, 2011 7:57 pm

Hello all

I set off for the shops yesterday in my traveller as it seemed a nice day. I got to the edge of my village and then bang! There was a lot of vibration, I thought I had broken a spring. Today I had a good look around and found that one blade had broken off and bent back double. It had cut a big hole in my radiator and nearly severed the brake switch wiring and just missed the brake pipe.

Reading here it seems a common failure so please check your fan blades.

Has anybody had a radiator repaired recently and what did it cost? Should I just exchange it with a Morris dealer or do the old style radiator repair shops still exist?

Thanks
Al


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