Ryobi weedwacker engine

[BentTooner]

Hi, again

Yes, I completely tore down the Ryobi engine and that's how I know the ring was broken. The parts to repair it were more than a used one in good condition off ebay.

That little primer bulb is easy to find but costs about $10 to replace. They always crack after they've been sitting, dry for a couple of years. A piston and rod assembly will run about $35. The flywheel is over $30. And so on. In the end, it's just cheaper to get one used.

That little Ryobi puts out about 1.6HP which is about the same as the 35cc Robin engine so it works great for a MB project. My Ryobi 2 strokes all got about 225+ MPG which is better than the Robin 4 stroke where I get 180 MPG. I never understood that...

The Robin has more low end torque since it's a 4 stroke. That's nice for hills.

I didn't bother with the starter because I just lowered the drive spindle onto the rear wheel after I was moving at a good speed and relied on a compression start. Works great and no need for the starter mechanism.

 

[MikeL]

Doh! I must of overlooked the part about the rings haha that would need a tear down I can't have high hopes since it's been sitting for so long.. this thing says 32:1 but what happens if I do 50:1? I still almost got 1 gal of pre-mixed 50:1

So with a 2 stroke I'm limited to a friction drive? I've been reading here and trying to figure this out.

 

[BentTooner]

Hi,

If you have 1 gallon (128 ounces) of 50:1 premixed fuel, you have about 125 ounces of gas mixed with about 2.5 ounces of oil.

To get it down to 32:1 ratio, you would add about 1.4 ounces to get it up to about 4 ounces of oil in the 1 gallon (plus the added 1.4 ounces of oil) of gas.

It's not necessary to be that precise but it's better to be too rich rather than too lean so I'd a little oil.

The pictures are great! That engine has a lot of wear and, FWIW, I wouldn't put any serious money in it - just some time, if you want. You could clean it up with carb cleaner but the primer bulb will have to be replaced and that's $10 unless you can get a used one somewhere cheaper.

You won't need the recoil starter mechanism if you're going with a direct friction drive.

No, you're not limited to a friction drive with a 2 stroke. I didn't mean to imply that. You can use any kind of drive you want (chain, belt, etc.) but the friction drive is the easiest way to get started.

If you haven't already, you might look in the gas tank to be sure it's in good shape and the filter is there, in one piece and tight to the bottom of the tank. Also, if you haven't already, you might want to check the fuel lines for cracks. I've found that the lines can leak, especially at the joints and the gasket at the bottom of the tank can leak, too.

In the end, you can easily spend $30 just getting little parts for an engine that is pretty worn. So, before you do that, you might check on ebay for a similar engine in good shape and see what it would cost you.

I've got at least one used Ryobi 31cc in my shop that I was using on a bike when I bought the Robin engine. I've also got a couple of the Ryobi 4 stroke engines that work well that I'm no longer using. And, I've got a NEW 31cc 2 stroke that I bought and never used except to start it to see that it worked. If you're interested in any of them, please let me know. I don't know where you live so I don't know if it would be worth it due to shipping costs.

You might be able to find one on a weed wacker at a yard sale in your area for dirt cheap, too. That would be best to save shipping costs.

Good luck! I hope this helps.

 

[MikeL]

Thanks for the help on the mix, so I've taken this motor apart and this is my first time taking a 2 stroke apart.. the piston top cleaned up good and as well as the cylinder head.. rings look a bit worn.. I might be able to get a little more life out of it, if not for a bike something else..

As for the fuel tank the filter is in it but all the fuel lines just pretty much broke upon touching them.

I just put the head back on so that was easy.. now for the carb the yellow and red adjustments are for the H and L carb adjustments right? The carb is pretty cheap so not much to do with that.

 

[MikeL]

updated shots before bed.. lubed with oil.. only one thing is I guess RTV gasket maker is not going to work for the cylinder head because it's not thick enough so the flywheel hits the coil.

having said that where is the clutch on this thing?? In the cutting head? it seems direct drive to me..

lol and how the poor shape this was in

Surprising the piston seals pretty good. I poured a decent amount of 2 cycle oil in the plug hole and let it sit for awhile and 10 min later it was still at the top.

 

[MikeL]

hmm this ryobi has no clutch which is odd they list a clutch cover in the parts manual.. seems to be from the 1997 era.