Hard to tell from the one pic. but if I have it oriented right that pic is of the vacuum breaker device on the top back of the china bowl. Is that correct?
A few more pic of the area up top can help. On ours 2004 models, there is a plastic cover over the top of that vacuum breaker. It is in the top back center of the bowl. Would be behind the toilet seat. If yours has one, take the cover off and have a look there.
See here for pics of mine.
The vacuum breaker is under the white plastic cover behind the seat. The little green Sealand sticker is on the cover.
Looks like this with the cover off
And from down below looking up
There should be a toilet model number sticker somewhere on the bowl. If it is still there. See ours
Let us know what your model is so we can look up the part diagram. Your manual should have one too. I know they changed somewhere in the 2005/2006 year as the sprayer was no longer offered.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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