what it is bro?

deacon · #1 (**permalink**) 09-07-2008, 10:56 AM

Okay quick background. I bought this engine on ebay and it didn't run just right. I tried to adjust the carb and it didn't do any better so I put on a new carb I had laying around. I do mean new not just an old one that was new to the engine.

Does the same thing. I put a hole in the muffler just in case it needed a better vent. Same thing.

I can get it to start no sweat. It will rev up... Sometimes it will take off and run great. Then for no real reason it will bog down. Sometimes I can let off the throttle a little and it will take off again and not do it for a while. Then when I throttle up later it will bog down. I let off and sometimes it will take off again and sometimes it will just keep dragging along. Two minutes later I varry the throttle and it takes off again.

I would think it was something I did except that it did it with both carbs. Maybe it's a leaky manifold gasket. I need to see if the manifold gasket is there cause come to think of it, I might have seen a piece of gasket laying on the ground outside the shop. I have torn apart so many engines it might have nothing to do with it though.

So what it is bro.

deacon · #2 (**permalink**) 09-07-2008, 11:06 AM

I wonder if it could be as simple as a clogged fuel filter. I did reuse the old one when I changed the gas tank. If that was the original problem it would still be the problem.

Large Filipino · #3 (**permalink**) 09-07-2008, 11:10 AM

It could also be your gas cap not letting enough air in. That's an easy check. Try running it with the cap off.

comfortableshoes · #4 (**permalink**) 09-07-2008, 11:52 AM

ON the side of the Ryobi 790r there is a allen head bolt- black and different from all the other bolts on the damn thing- Mine was loose and had a lot of the same issues your describing, when it got really loose my engine would start up, race and then die.

One I figured out the issue I tightened that down and man she's been sweet to me ever since.

On the gas cap issue- do you have the original ryobi cap? he stock cap is black and yellow, tightened down there is a really nice venting system that works well.

Did you check your: fuel lines, bulb etc? I've read alot on here about those being the source of some major issues with the weedwackers.

deacon · #5 (**permalink**) 09-07-2008, 12:52 PM

I have my own gas tank with vented cap, but I will check cause it might well be the issue.