RV Repair: waste tank odor, ford rv, american cobra

Question
Hi Ron. We own a 1988 Class C American Cobra Ford RV. 25'. In  the fall, we drained everything including the waste tank throughly till it ran clear then winterized it. We just got back from Florida for 3 months and went inside to check and smelled a strong odor we thought it was coming from the bathroom. Ironically it wasn't. We keep that door shut and there is hardley any odor at all but you can smell it though the whole rv. It is extremely strong. We aired it out, but closed it up again since we have had a lot of rain. When we opened it up again, it was just as bad. Other than that, she runs real well with no other problems.We just bought it last year and have "some" experience with it.We also live quite far from an rv center. Thanks for any help you can give us.

Answer
Did you flush all the corners of the holding tanks, I will bet you did not.  You can buy a "wand" at any RV retailer that does a good job getting at the corners of the tanks.  Also, make sure the vents that go up through the roof are not plugged.
I had a similar problem with one I owned until I started using a little Clorox in the holding tanks a couple of times a year, cleared it right up.
Lastly and may sound strange, did something crawl up into your RV and die. Check it out!