[AMRadio] Balanced tuner

[CL in NC]

I have been using a Heath 2040 tuner with my 130ft dipole for many moons.  I recently got a fixer upper Johnson Matchbox, the 250 watt size, and restored it by replacing burned contacts from an apparent lightning strike.  Seems to work fine, but I need to know what some of you get dial reading wise if you have a similar dipole.  Feeding the matchbox through all the same lines and SWR meter, on 80, the tuner seems to work well and gives me good matches from end to end.  On 40 though, the Matching dial stays at 95-100, and tuning runs from 5 to 30 and am unable to get a perfect match, ranging from 1.2 to 1.5.   The Heath tuner will give me a perfect match everywhere. The question is, since the Johnson is a balanced tuner and the Heath has a balun, is the Heath masking the real quality of the antenna and feed when compared to the Johnson?  I tried it on 20 to 10 just see how it worked, and it did OK, but still unable to give me a 1 to 1 where the Heath will, but since  I don't use my dipole above 40, not a concern.  Any thoughts on why the Matching dial likes to stay at 100 on 40 meters?  Maybe an feedline length vs antenna length conflict?

Charlie, W4MEC in NC