Ryobi Strimmer - Primer Bulb

Reply

  #1  
Old 04-10-16, 03:38 AM
Member
Thread Starter
Join Date: Apr 2016
Posts: 4
Ryobi Strimmer - Primer Bulb

Hi, I'll try and make this not sound too confusing..

Last week I was using my Ryobi 2 Stroke petrol strimmer, Everything was working fine with it, started fine, ran fine ect...

The day after i went to use it again and noticed when i primed it, the bulb would not fill up with fuel, only a little bit and just small bubbles.

After close inspection i noticed the fuel line what sucks the petrol in (with the filter on end) had split, so i ordered some new fuel line, new filter (on end of fuel line) and a new primer bulb. Fitted it all but still had the same problem.

So next thing i thought maybe the carb is blocked somewhere so i removed the carb gave it a full clean from top to bottom, refitted and still same, the primer bulb would not fill.

So i ordered a rebuild kit for the carb. Rebuilt it by following a video on youtube. Refitted the carb, still no luck.

As i was trying to prime it, my friend noticed quite a lot of fuel dripping from the bottom so after close inspection i noticed the new fuel line i fitted, the fuel was leaking over the top and realized when i pulled it off the carb it came off too easy (and also went back on too easy) not really much give so im not wondering if this could be the problem???

I have tried everything and just cannot get to the bottom of this hope somebody can help me .

Oh by the way, I noticed aswell (for some strange reason) when i loosend the right screw which holds the primer bulb in the fuel came into the bulb really fast but when primed it was leaking also sometimes when the bulb was pressed it didnt come back up (until i loosend that screw). Strange
 
Sponsored Links
  #2  
Old 04-10-16, 06:00 AM
Member
Join Date: May 2006
Location: Iowa!!!!!
Posts: 3,728
The filling of the primer bulb or the bulb not coming back up to its starting position can have to do with the reservoir diaphragm not compressing on the lever that actuates the needle valve in the carburetor. The primer is just a little pump that pumps air, then fuel from the reservoir, through the primer bulb, then on to the tank. It's purpose is to get the air out of the system so the choke can do its thing to get you started cold.

If the diaphragm is perforated or if the needle valve in the reservoir chamber is stuck the fuel can't circulate and you get a primer that isn't filling. Any blockage through the carb and onto the fuel tank get you the same thing. Or an air leak in the lines or a filter in the tank that isn't submerged in the fuel gets you the same thing.

The thing you're seeing with loosening the screw to make it work is usually a kinked fuel line that leads to the primer. You tighten the primer screw it pulls the primer in towards the carb, compresses the line, stopping the fuel flow & sticks the primer bulb down. Just check the fuel line and reroute it.
 

Last edited by marbobj; 04-10-16 at 06:16 AM.
  #3  
Old 04-10-16, 07:42 AM
Member
Join Date: May 2006
Location: Iowa!!!!!
Posts: 3,728
Also, In rereading this I notice you said the line came off and went back on the fitting easily. That sounds like you may have the wrong size fuel line. There are a few variations.
 
  #4  
Old 04-12-16, 06:20 AM
Member
Thread Starter
Join Date: Apr 2016
Posts: 4
Update...

i received the new fuel line today, 2mm i/d, 5mm o/d. Installed it fits loads better no leaks ect which was a good sign.

I also removed the carb again, took all parts off and gave it another good clean only this time i found a really thin wire, the kind whats used when you buy new cabling ect with a black coating, just removed black coating so it was bare and cleaned all tiny small holes ect....

refitted the carb and thankfully the primer bulb now fills and primes as it should .

But there's another problem.............after priming 3x/4x times as stated, i put the choke on the lowest one pulled 2/3 times it fires up then cuts out..so i then put choke half way, pull once/twice and starts straight away, it idles over really well from what i can tell by the sound of engine but the problem is when i put choke onto "run" (there a little symbol of a man running lol) it just dies and bogs down....when i try putting any throttle on it just dies so now im stooped?????

another question ...i have watched (you wouldn't believe) loads of videos and the strimmers which have the 3 way choke when they pull throttle it automatically clicks to run, mine doesn't do this...is this normal??

just to clarify, if the strimmer "ticks" over or "idles" ok, by that i mean it doesnt sound like it struggling, starving for fuel ect...or it doesn't sound like its revving to much it litreally ticks over until i stop it. So does this mean the carb, fuel line ect is all good does it just need adjusting?
 
  #5  
Old 04-12-16, 09:05 AM
Member
Join Date: May 2006
Location: Iowa!!!!!
Posts: 3,728
The auto kick off on the choke is a model specific feature. Some would have them and others wouldn't.

Sounds like it just needs adjusted. You may have one or two mixture adjusting screws. Since you already have it idling fine, look on the side of the carb for a couple of screws that look like setting types. Often they are marked with an "H" and an "L" for high and low respectively.

If there are two, start it up and set the L for max rpms at idle, then the H at max rpms at full throttle. Now check the throttle for responsiveness. It should snap right off. If all's well there reset the H screw at wide open throttle to get a small noticeable drop in rpms - about 1/8 turn out (counter clock) usually. That's to ensure lubrication in a two stroke, so don't forget to do that.

Now go back to the idle speed and set it at a speed the head just starts to move. If the head spins all the time normally, then you don't have a clutch, so leave the idle speed where you have a good idle.

If you just have the one setting screw, skip the parts on the "L" screw.
 
  #6  
Old 04-12-16, 09:35 AM
Member
Thread Starter
Join Date: Apr 2016
Posts: 4
hello mate thank you for your reply, i know which screws you are on about, i have seen videos on this but mine seems to be different, this picture is same as mine [ATTACH=CONFIG]64991[/ATTACH], then the next picture is the most common one ive seen in videos which requires a special tool to adjust Name:  index.jpg
Views: 275
Size:  6.4 KBi have tried having a mess around while strimmer is on idle but i cant really seem to notice any difference, only when i turn the large screw which adjusts the throttle a little bit. Am i doing something wrong?
 
Attached Images  
  #7  
Old 04-12-16, 10:05 AM
Member
Join Date: May 2006
Location: Iowa!!!!!
Posts: 3,728
The limiters on the screws are usually rooted in emission control. They're pretty common. The range you can turn them usually gets the job done.

The top of the carb is the pump and the underside has the four screws in the plate that covers the fuel reservoir. Usually the pump has a gasket and a diaphragm. The diaphragm lays in first, then the gasket. On the fuel reservoir, the gasket goes in first, then the diaphragm with the disc on it.

The needle valve that controls the flow of fuel is fitted with a lever. The end of that lever has a spring under it and the metal disc on the diaphragm has a small tit on it that pushes against the lever that in turn lifts the needle valve. All that controls the flow of fuel. That lever with the spring in place and the retaining screw on the pivot should rise up to be level with the casting.

When you assembled the carb do you have all that in place?
 
  #8  
Old 04-12-16, 05:27 PM
BFHFixit's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Jun 2007
Location: USA.
Posts: 1,836
The auto kick off on the choke is a model specific feature. Some would have them and others wouldn't.
Ryobi does not have this.

If all's well there reset the H screw at wide open throttle to get a small noticeable drop in rpms - about 1/8 turn out (counter clock) usually. That's to ensure lubrication in a two stroke, so don't forget to do that.
This also helps in cooling and assuring sufficient fuel supply under a load.

The limiter caps can be removed and sometimes all that is needed, is more adjustment than they allow. !!Be warned that improper removal can result in the jet being broken off flush to the carb rendering it un adjustable.

There is more than one way to skin a cat, my steps differ a bit, but yield the same result. I find it easier to get the high set somewhat in range first, adjust the idle screw for a higher idle so it will stay running, then adjust the low until it steps up off of idle to full throttle without hesitation. Then back the idle down to set so the clutch just is about to engage, then repeat the steps for high makings sure to get the noticeable drop in rpm. The low will affect the high, but the high should not affect the low.
 
  #9  
Old 04-19-16, 12:28 PM
Member
Thread Starter
Join Date: Apr 2016
Posts: 4
still having problems

i have gone to extent in buying a new carb because it started running very poorly, fitted the new carb the day i got it, it idled on lowest choke but when applying throttle (this new carb has the feature where it clicks straight to run when throttle is applied), but i had to be very generous with the throttle and too much made it bog down and cut out................now (for some reason) when i start it with choke and lowest one, it idles very quick and longer i keep it running the higher rpm's get but will no now run on "run" throttle at all....i give in lol
 
  #10  
Old 04-19-16, 01:15 PM
Member
Join Date: May 2006
Location: Iowa!!!!!
Posts: 3,728
Never give up. The mixture is too lean. That causes a two stroke to ramp up the rpms.

You could have an air leak possibly at the mounting of the carb to the manifold or at the crank seals. The best way to find something like that is to spray WD40 or carb cleaner around the mating surfaces and see if the rpms change. If so that's the leak point.

It may also be an adjustment, although the rich mixture that causes a boggy throttle doesn't contribute to the higher rpms you're seeing. It's usually the lean mixture and often an air leak.

Try a complete reset of the mixture screws. Get it warmed up first.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes