I need help troubleshooting my cutting torch. I can get a good flame after lighting the torch and balancing the oxygen and acetylene gases. I have the cutting valve open all the way. When I depress the oxygen cutting handle my flame changes to an unbalanced flame that isn't hot. It makes more noise and I can tell it is blasting more oxygen into the mix, but the flame is white and large and not cutting the steel well. I am learning this art on my own through textbook and DIY manuals (a few YouTube videos as well). I apologize for my ignorance in advance. I have checked the hoses for kinks and cleaned the tip with my round file. I had the torch handle into my welding supplier where they cleaned up one regulator valve (old handle of my grandad's). I'm at a loss now and think I may have to buy a new handle.... Thought I would solicit your collective experience before I started spending money troubleshooting....

When you say "cutting valve open all the way" which valve are you talking about?
There are three. TWO on the handle and ONE on the cutting attachment (Victors terminology) .

The valve on the HANDLE that controls oxygen, when using a cutting attachment, should be open all the way.
The mix of acetylene and oxygen is trimmed by the valve on the cutting attachment.
I like to get it close before hitting the oxygen lever, then fine tuning it with the oxygen lever pressed. 

Unless you adjust your regulators for each metal thickness (in that case the acetylene valve can be full open),
the acetylene valve will set how hot you flame will  be. Thicker metal, turn it up and or cut faster.
It is a balance of heat and travel speed plus steadiness that make a good cut.

I like a clean tip with a good long feather.

Floyd