Does anyone have an idea of why our tiller wants to dig deeper and deeper?
It's like we have to muscle it to go forward.

this is an older tiller , but just like the one we had before {son has our old one now- and it never had this problem}

The only thing that seems to be different is the tines are very slim - like they were sharpened a lot by the previous owner.

the tines on our old tiller were fat and not to sharp cause we never sharpened them, they always worked fine as is.

not sure if the adjustment of the wheels should go up or down and same with the stinger- up or down?
tried a few changes and makes no difference.

I actually still have and use my Daddy's tiller (circa early 70s) it is a beast if the tines are sharpened it "will dig you straight to China". It takes muscles to pull back on it so that it will go forward instead of down. When they are dull it works easier.
Just had a funny thought... with my leg doing the hokey pokey wonder what I would look like out in the garden behind that beast now ROFLMAO

Thanks for that info, that is about the only difference between the 2 tillers that I can tell.
I'll have son will bring the tines from the other one and we can try them out before doing any welding on this one.

I got a real workout yesterday from it. gotta get it fixed. I'm thinking we can weld some extra metal onto what is there...just to beef it up, they really sharpened it a lot. thin & pointy edges.

yep that is probably it Daddy always had it so it would "cut through the grount better you have to have it sharp".... Hasnt been sharpened since last time he sharpened it and he has been gone for 28 years. sure worked better for me in the past with it dull if opening up new are taht is a bugger but it but it will dig right in if yu hang onto it properly