After a year and a half of happy use of my 850, I had a very messy occurrence on my last brisket cook. Grease flowed out of the drip pan drawer and onto the shelf below. I thought that the foil pan had overflowed, but it was only maybe 1/2 full, WTH? Then another user, captgadget, also posted the same issue.
First, I called Traeger support, they looked it over via video chat, could see nothing wrong. We poured a quart of water into the grate pan, it ran down into the drawer with no leaks, hmmm. I asked them about replacing the bottom high-temp cloth gasket sealing the drawer, they said that it's not a replaceable part! (but it is replaceable actually). They offered to send a new drawer, but mine looks like new.
So, I decided to nerd out the grease pan to see how it works and what can be improved. The bottom line is that there is a critical place that you need to be sure is kept clean. Cooking at high temps with small amounts of drippings can build up grease in a place that will cause leakage until removed. Sorry for the long story but read on if you are interested.
Normal Operation;
1 - The grease pan sits in its drawer, the top cover plate seals against a high temp cloth gasket, this is NOT a grease seal, it's there to seal the drawer to the barrel which prevents most of the exhaust and ash from venting thru the lower pan. After closely looking this gasket over, it is replaceable, and is clipped in place just like the hood gasket should that ever be needed.
IF you INVERT the top plate, the grill will drain OK, BUT it will not be sealed to the barrel, exhaust will flow thru this area and may overheat things, beware.
2- The final drip channel steeply drops down to the square bottom tube and into the drawer below. The key point to notice here, is that that channel overhangs the down tube about 3/8" to 1/2". This means that grease drips off the end of the channel, basically right down the center of the tube and into the drawer below.
Here is a sketch of the normal flow of drippings into the pan;
View attachment 3041
This is a pretty clean setup, BUT, it does need maintenance, something I've not seen covered before.
What I just had happen after my greasy brisket cook was that grease did drip into the drawer, however, it also leaked grease onto the top cover of the drawer and then ran out thru the slot in the back of the drawer where the top plate's locking tongue inserts into the drawer frame!
So here's the issue, after many slow cooks, high temp reverse sears etc. Grease had collected under the spout tip and it filled in the space behind it. This allows grease to not only drip, but also "wick" and run down the side of the down tube and into the gap around the heat gasket. It then continues onto the drawer top cover, then flows to the back of the drawer and out of the slot for the cover top. Here's a sketch of that;
View attachment 3043
So, the key take away is to get in and really clean the end of the drip channel. It was a pain to get in there from below but that was the best access. I used a flat blade screwdriver to scrape out all of the old burned up grease, but that was a years worth. My grill is now insulated so this grease channel doesn't get near as hot any longer so it will be easier to just wipe down regularly.
In general, if clean, this system works just fine and one brisket does not overflow the pan. That said, I will probably use a large pan with a splash of water, on the lower shelf with the brisket on the middle shelf to cut down on the clean up.
One of the reasons I chose the timberline was for the invisible grease system and no smoke stack, but that's just my preference. They aren't as straight forward as the classic bucket (something I've accidently knocked off my old grill at the worst possible times!) but they do work.
Next up, small mod to the drawer, in case a small leak occurs...
