Ryobi cultivator 410 r tiller

try www.jackssmallengines.com for parts carburetor has something not allowing the needle to seat properly

try and run it with the muffler off the screen inside might be plugged if so open the muffler and clean the screen they are made to open

the mixture is usually on the machine somewhere--if not go the honda website and look up info for that model

Exploded view:-
http://www.outdoordistributors.com/pdf/Ryobi/RYOBI-410.pdf

Did you replace the gasket (item 15 on the linked document) when replacing tank and lines, if you didn't and the old one has been torn it could be sucking in air, also the 4 carb mount screws need to be of equal tightness

If it is a 2 cycle, use 2-cycle oil. If it is a 4-cycle use the oil mentioned in the manual. If no manual, I would use a 30 weight oil. Good luck...Lee

some of the new models are 4 cycle, hence you dont mix it.The 2 cycle models are all 50 to one of a good synthetic 2 stroke oil

Here is a link to parts listings, when searching put in the work Cultivator and it gives you a few options. Hopefully the pictures will let you decide which one is yours.
http://hcpi.arinet.com/scripts/EmpartISAPI.dll?MF
Here is a link to find a dealer in your area that can help you http://go.mappoint.net/homelite/PrxInput.aspx
good luck Tom

Definitely stay away from Ryobi, Troy Bilt, Bolens and Yard Machines by MTD. They are all Ryobi with different brand names on them. (goes for trimmers too) MTD owns them all. The best small tiller, IMHO, is Mantis. (2-cycle) I think Sears sells them now. I have one and it will run circles around the rest.

If it's a Ryobi it is 40:1. If you go to the store, you can buy small bottles that will give that mix if the entire bottle is put into 1 gallon of gas. Ryobi bottles are pretty easy to find. Home depot carries them.