New noise

[Binky Tremain]

Have developed a new noise…comes from up front, up high, generally when throttle is advanced. At first I thought the fan was throwing something around, or the hood had become loose and was clattering…that’s what is sounds like. Does it, stops, does it, stops. Can’t seem to narrow down the source.

Just got her a few days ago, and just started. Thanks all!

[indy61]

Sounds like it might be a bad bearing in the generator or a bad fan hub.

[Crimson Tim]

Right side or left side?
Has your fan been oiled recently? Fan shroud loose? Radiator cap askew? Can the fan touch the shroud? Any hood or dogleg fasteners missing? If it still has a generator, those still want a few drops of oil periodically, don’t they? There’s not much stuff high and forward, so it doesn’t seem like it should be too difficult to find. Have you heard the trick about using tubing as a stethoscope to pinpoint where sounds come from?
Also, post a video. Maybe someone will recognize the sound.

Edit: check engine oil and hydraulic fluid and function. Maybe your hydraulic pump drive gear has come loose and is about to fall off the shaft.

[Binky Tremain]

Left side, have not oiled fan yet (can’t find screw, unless it’s been painted over). Everything seems tight, nothing missing. Almost sounds like the clattering of the exhaust flapper, but continues when held open. Actually, I can hear it when listening atop the exhaust. Took it off and shook it, but nothing dropped out.

Still trying to pinpoint.

[Binky Tremain]

Sor…Have been converted to 12 volts, and have no hydraulics.

[Pap]

Hey Binky welcome to the forum. Sounds like you got one of those things that makes it fun to have a Cub.
I'm not going to suggest anything. Sounds like indy61 and Crimson Tim already had some good things for you to do and check.
Good luck I hope that you find out your problem.

[CharlieK]

on my old antiques I was told to turn up the radio

[Pap]

Yup

[tst]

take the belts off and run it to see if the noise is gone, if so its the fan or generator

[Crimson Tim]

Walnuts down the exhaust stack?

[Glen]

Hi,
The Cub owner's manual shows how to oil the fan hub, if you need the info.
You didn't say what year Cub you have.

If the hub doesn't have an oil screw, it might have a newer replacement fan assembly, some or all of those have sealed bearings, there isn't an oil screw in the hub on those, they have said on here before.

[Binky Tremain]

It’s a 1948. I have the service and owners manuals coming in Friday.

I’ve checked a number of times and even scraped paint on hub…no screw. I’m new to this, but fan replacement doesn’t seem too bad. Trying to capture it on video.

[Cubfriend]

Is the nut on the alternator loose allowing the alternator fan to wobble?

[Binky Tremain]

Having trouble attaching video. Have posted it on facebooks Farmal cub repair and maintenance page.

[tst]

they did make a replacement fan with sealed bearings so you may have one of those if there is no screw in the hub