Ryobi 790r gas trimmer

If your fuel filter is clean, and none of the fuel lines are pinched, then you probably need to replace the diaphragms, gaskets, and screen in the carb. Some carbs with the primer bulbs mounted on the carb have a check valve in the primer system. This is the least likely problem, but it is possible that the check valve is defective.

Here is a page that will take you to a download of the exploded view of the trimmer ..
http://safemanuals.com/user-guide-instructions-owner-manual/RYOBI/790R-SERIALS-810046371-THRU

on the right side there is a place to select the download .

That pin should be the same as other Ryobi trimmers. Find one for one of them and compare. Lee

This link will take you to the specific four tooth blade you can put on a Ryobi 790r. Cheers!

http://www.ereplacementparts.com/4tooth-blade-p-283522.html?osCsid=5lrh04vo7vs660lfcg0ku8ben2

The window ratio should be fine between 40/1 to 50/1.

Reduce oil ratio by increase gas part if some unburned oil can visible from the exhaust.

Someone else could have a better voice on this matter..

On the 790R you will have to remove the carburetor and the four screws of the plastic housing behind it. The gas tank will then slip out.You will need to replace both the housing and carburetor gaskets.

Hope this is of some help, Lamar

Maybe a quick fix and maybe not
check your muffler the factory puts a spark arrestor screen that tends to plug after awhile
there is a little plate on the side muffler that needs to be removed to access the screen you may need a torx bit or allen wrench to remove
you may have to remove the back half of the plastic cover to access the screws
remove screen and clean with carb. cleaner or equivalent make sure you can see through it and reverse the procedure to put it back

I don't mean to over simplify this, but are you using fresh gas? Gas string trimmers are extremely ticky when it comes to gas. They like it SUPER fresh. And while the gas and oil mixture should be right, it can be off a little bit and still run. Try draining all of the gas out, and then filling up with fresh mix. This is ALWAYS my first step with string trimmers, and it fixes the problem 75% of the time.
Hope this helps!!

chad

Hi

Check the spark at the plug,compression and carburation.Clean the air and the fuel filters.Check the muffler.

best regards savumihai71