Self propelled mower wont start unless i use starting fluid?

[ohioboy15]

I have a B&S Quantum power 5hp self propelled engine on a MTD yard machines 21in self propelled deck(or base whatever its called lol) It says on the engine model type: 124782-3197-01 and Code: 9405055. This mower i bought used and its in pretty nice shape but when i bought it from someone he said the rings or something needed replacing because it burns a whiteish blueish smoke from the oil, Well i tried every type of oil to help that and i found the 5w-30 i think it is which is like the thickest i could find and it helps very much and hardly ever smokes. It still goes through oil very quick so i have to put more oil in each time i cut grass(my yard is about 2/8th an acre) which doesnt bother me too much. Since i have bought this mower though it has never started on its own, i have always had to use starting fluid to get it going and once i just do a quick spray or sqirt of it it starts up on the first time and works pretty decent. Also since i have bought it,it has never had a air filter in it(i know not good but im on limited funds) so i dont know if that has something to do with it or what but it has a new spark plug and all so thats good, but if you have any clue please let me know any ideas and use some details because im not too smart with part names and such but i do know how to take them apart and back together(well atleast push mowers, never done a self propelled before)
Thanks

 

[Lawnranger]

Does the carburetor have a primer bulb? If so, is it damaged? Is there a manual choke? Does it have an automatic choke and if so, is it working? If the rings are worn, the engine may not produce enough initial vacuum to draw fuel from the carburetor but once it's started it can. You just may have to use some type of starting fluid on this engine until it's repaired or it dies.

 

[ohioboy15]

Well i went out and got brand new gas line since the other line was worn to bits and cracking all over, now there is alot of air in the new line and i cant seem to get air out. Any ideas? also the carb was very clean inside the bowl and all is nice and clean(i didnt even need to clean it) also im not sure the difference in auto or manual choke also yes it does have a primer button and has a little crack in it but could such a small crack cause that problem?

 

[Lawnranger]

A small crack in the primer bulb may prevent it from priming the carburetor properly and that could be the reason you need to use starting fluid to get it started. Replace the primer bulb and see what that does for you.