Osburn 1100 - Air Control Plate Play

[Snoman]

I have a pretty old crusty Osburn 1100 that has been a little unpredictable from an air perspective. It will occasionally just take off while it's cruising / damper nearly closed and kind of feed itself more and more air and continue ramping up. The air control damper does work... somewhat, but I've always felt it to be a little suspect.

I sealed the ash plug, and did put in a key damper last year and it helped quite a bit, but I decided to take a look at the air control plate / assembly underneath it this week in prep for winter; 1. to lube it up a bit because it has some surface corrosion all over the place that causes some binding in the control rod, but also 2. just to look at the mechanism a bit more closely.

There are basically 2 channels that hold a thick steel control plate that has a penny-sized hole in it. What i noticed is that there is some play in this plate- I'm able to push it up and down in the channels- maybe 1/16" gap? Is it worth taking a small hammer and trying to close some of this gap a bit after i clean everything up? I have to imagine air just rushes through it from the sides. Anyone have thoughts on the matter? Any recs on lube to use? I was going to use something like graphite.

 

[EatenByLimestone]

Graphite is a good high temp lube.

Air is certainly getting in around that plate, but it must be designed with such loose tolerance.

How tall is your chimney?

 

[stoveliker]

Tightening it up and then having things expand when it gets hot may result in bigger problems imo..
So be careful.