Roper 8 hp Won't Start

[Berniebac]

That is your main nozzle and make sure the small holes are clean.

I have finally gotten back to working on my Roper (B&S) engine. When I last posted I could get it to run by pouring gas in the cylinder, putting the plug back in, and turning it on. It would run for a couple seconds till the gas burned off.

It would not run when I hooked the fuel line to the carb. So today I pulled the carb off. When I pulled the fuel line, gas ran out of the line till the tank was empty. So I assume gas is not entering the carb. When I took the bowl off there was no gas in the bowl, that seems to confirm that none is getting past the first needle that lets it into the bowl.

I also noticed that the float does not sit parallel to the carb body. (See attached pic). It sits at quite an angle to the body. I read somewhere that it should fit parallel to the body, so I think I will adjust that first. I also pulled out all the needles, the main nozzle, and the nozzle that the main nozzle sits on top of. Cleaned all parts with carb clear and poked a small wire through all the tiny holes.

I will add another post with additional pics of the carb in just a few minutes. I hope you will recognize it and offer some suggestions.

I appreciate any help in trying to get this thing to run again. I would like to get it to run, before I spend any money on it. If it goes, I'll probably get a carb kit and see if it helps. I don't think I would recognize a bad seat, or a worn out needle so I don't know if new parts would even help.

 

[Berniebac]

Some additional pics of the carb torn apart on my work bench.

 

[Rivets]

Looking at your pics I think you have found the problem, float height. It should rest parallel to the base. You will need to adjust the float tab. After you adjust it blow on the fuel inlet ( with your mouth, I hope you don't mind) and see if it holds pressure. If it does put the carb back together and try it. If it doesn't you will have to put a new needle and seat in. Good Luck

 

[Berniebac]

Looking at your pics I think you have found the problem, float height. It should rest parallel to the base. You will need to adjust the float tab. After you adjust it blow on the fuel inlet ( with your mouth, I hope you don't mind) and see if it holds pressure. If it does put the carb back together and try it. If it doesn't you will have to put a new needle and seat in. Good Luck

I reset it to parallel and blew into it and I could blow air into the carb. I did this before I read your post and I thought that was a good thing. If air goes in, gas should go in. I reassembled the carb, put it back onto the tractor and hooked up the gas line. The gas flowed right thru it and onto the ground. As soon as I saw that, I did not try to start the tractor.

I guess that means that the inlet valve controls the flow to the point that gas will not go into the bowl until you try to start and run the engine. I suppose if the bowl was full from the last use it would start on that and the engine vibrations would make the needle open and close to allow gas into the engine.

While it was apart I looked at the needles under a magnifying glass and they looked scored, maybe even bent but hard to say.

I will order the carb kit and giver her the overhaul. At least I got gas into the carb, I have spark, and I can get it to roll over. Not a bad place to begin.

 

[Berniebac]

I also noted that my inlet needle did not have that little viton tip on it. I wonder if it is supposed to?

Thanks for your help.

 

[Rivets]

First, did you have it turned upside down so that the needle is closing the seat. if yes rebuild. You could try this first for fun. Disconnect the fuel line and see if you can start the engine. If it starts let it run until all the fuel is removed from the carb. This will tell you if everything else is working. It may not run smooth, but at least you'll know it works.

 

[Berniebac]

First, did you have it turned upside down so that the needle is closing the seat. if yes rebuild. You could try this first for fun. Disconnect the fuel line and see if you can start the engine. If it starts let it run until all the fuel is removed from the carb. This will tell you if everything else is working. It may not run smooth, but at least you'll know it works.

Do you mean have it upside down when I blow into it? I think I had it right side up when I blew into it and air would flow into it. I was thinking the same thing about trying to start it. In an earlier post you had suggested pouring a little gas into the carb and trying to start it. I will give it a try in a few minutes when the fumes die down.

 

[Rivets]

Upside down so the needle is sealing against the seat under the weight of the float.

 

[Berniebac]

First, did you have it turned upside down so that the needle is closing the seat. if yes rebuild. You could try this first for fun. Disconnect the fuel line and see if you can start the engine. If it starts let it run until all the fuel is removed from the carb. This will tell you if everything else is working. It may not run smooth, but at least you'll know it works.

I just tried to start it but it would not run on the gas in the bowl. Not a kick. It did seem to blow some gas back out of the carb when I stopped rolling it over, I don't mean gas, but almost like a steam rose out of the breather hole. I don't have the air filter, or the metal cover in place while trying this.

 

[Rivets]

Just let some gas into the carb and see if it will start with the choke on or off. Try both ways