# Smoke Unit #312 AC



## Lairbear (Aug 20, 2012)

Is the whistling noise normal after the chuff sound in this unit?
If it is,what can be done to eliminate the whistling noise?


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## tjcruiser (Jan 10, 2010)

Lubrication, maybe? This thread may help ...

http://www.modeltrainforum.com/showthread.php?t=4883

TJ


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## Reckers (Oct 11, 2009)

If you have a cycle of a chuff (caused by the piston being driven into the cylinder, forcing air out the top) followed by a whistle, that may be caused by air being sucked into the cylinder as the piston backs out of the cylinder. See if you have some dirt pluggging the air intake?


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## Lairbear (Aug 20, 2012)

The hole between the "output" of the piston and the input "partition" is clear, what else could be causing this phenomena?


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## Nuttin But Flyer (Dec 19, 2011)

My 312 is S.I.T. but I am not familiar with the 312AC. Is yours S.I.T. or S.I.B.?


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## Lairbear (Aug 20, 2012)

I'm kinda slow this morning...What does S.I.T. or S.I.B represent?


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## gunrunnerjohn (Nov 10, 2010)

S.I.T. - Smoke In Tender
S.I.B. - Smoke In Boiler


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## Lairbear (Aug 20, 2012)

Thanks grj,

It's a S.I.B.


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## Nuttin But Flyer (Dec 19, 2011)

I'm pretty sure it's the same concept for all American Flyer units that have S.I.B., a link-driven piston into a small cylinder that chuffs the compressed air out of a small opening. It may simply be that it needs and good cleaning and lubrication. Has this item been sitting for years and only now attempting to bring back to life?


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## Lairbear (Aug 20, 2012)

I've had the unit apart and cleaned same, applied three in one motor oil inside cylinder and moved the piston by hand; I can hear the chuff sound with the whistling sound as well. I did clean out the small holes in the cylinder end as well as the baffle plate hole.
I haven’t removed the baffle plate to check for a difference in sounds between the cylinder hole and the baffle plate hole. I presume if I enlarge the baffle plate hole, the forced air will diminish in forced volume into the chamber and less smoke will come out?
Is the whistling noise a characteristic of the units?
A cleaver engineer at AC Gilbert designed this device.


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## Nuttin But Flyer (Dec 19, 2011)

As I mentioned above, this unit is pretty much the same for all AF steam locos with S.I.B. I have several of these and none of them whistle -- I have no clue on this one. Certainly if I run across one, I'll be back here to write about it. Sorry I can't help. There are plenty of others who visit the forum here who might be smart enough to figure it out. So don't give up.


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## Nuttin But Flyer (Dec 19, 2011)

I just thought of something you might try. Thomas Barker is a fabulous Flyer enthusiast who wrote a Servicing Book on Flyer items. Here is his email address....

[email protected]

Try writing to him about this issue. He might be a lot more helpful at determining what causes it. He is usually quite helpful when other Flyer owners have issues like this.


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## Lairbear (Aug 20, 2012)

Good news, the whistling noise is gone from the smoke unit.
I checked the holes again at the end of the cylinder, baffle plate and input to the chamber, plus coated the piston with Vaseline and voila, no more noise other than the
chuff sound.


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## gunrunnerjohn (Nov 10, 2010)

Lube works wonders.


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## Nuttin But Flyer (Dec 19, 2011)

Nice to know that tip for the future. Thanks for sharing.


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## AZ-Flyer (Oct 18, 2011)

Lairbear said:


> I've had the unit apart and cleaned same, applied three in one motor oil inside cylinder and moved the piston by hand; I can hear the chuff sound with the whistling sound as well. I did clean out the small holes in the cylinder end as well as the baffle plate hole.
> I haven’t removed the baffle plate to check for a difference in sounds between the cylinder hole and the baffle plate hole. I presume if I enlarge the baffle plate hole, the forced air will diminish in forced volume into the chamber and less smoke will come out?
> Is the whistling noise a characteristic of the units?
> A cleaver engineer at AC Gilbert designed this device.


What I have done, that works is put a little insulation between the baffle plate and the piston chamber. To much will lesson your smoke, to little you will still have the whistle sound. Put just right works great.......It doesn't take much.

The only time I had to enlarge the baffle plate hole was on the 4-8-4 #800 from Lionel. Then I also had to counter bore the piston chamber from the piston side. 

AZ=Flyer

My Classic American Flyer Cabinet-top Train Layout


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## flyernut (Oct 31, 2010)

Vaseline is the #1 choice for lube in the piston chamber.


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