HELP! Problems with Older Leahy Incubator Holding Temp

[nate_o23]

Hi all. I bought an older Leahy Incubator last year and spent the winter going through it.
I replaced both wafers and micro switches and rewired everything. Also upgraded fan and replaced heater with two 250W strip heaters. Figured I should have a good incubator but so far has not worked that way.
Heres whats happening. I have #1 wafer set at 100 and #2 set at 101. It kicks out at 100 every time, problem is temp continues to rise to around 102 then slowly falls all the way to 95 before heater will kick back in. That seems WAY to wide of a fluctuation. My hatch rate has been horrible.
What should I do??

 

[chickengeorgeto]

First consider where you have your incubator sighted. Drafts are bad for keeping incubators operating on track. So are air vents, and windows, especially if the Sun shines in.

 

[nate_o23]

Its in a pretty good spot, north side of house. No direct sun, drafts, temp swings, etc...

 

[nate_o23]

So I was messing around with the incubator today and I think I figured out what is wrong but not sure how to fix it.
I took temp readings top and bottom and bottom temp was around 104 while top was 96. This was with the heater off. Seems like an air circulation problem but I have a new Dayton Motor in it that seems to be pushing plenty of air. The curved metal deflectors are both there as well.
I just dont get why I have such a temp difference top to bottom????