4 stroke small engine nuts needed.

[Terryl]

OK all you small engine nuts out there I need some help.

Due to a manufacturing defect on a Ryobi 825R string trimmer (5 years old) I had to replace the magneto assembly, the spark plug wire was pinched between the top cover and the rocker arm cover, after a few years like this it finally shorted out the ignition module (built into the magneto assembly) and it quit, I ordered and got the new one in the mail but have one problem, it didn’t come with any instructions on what to set the spacing from the magneto pickup to the rotor magnets at, there is an adjustment of almost a .125 of an inch.

Instead of tearing it apart several dozen times and trying by pure luck to get the right gap I need someone that may know what to set this to, I rely need to get this running as the weeds around the fence posts are getting out of hand, I don’t want to send this out for repair as I’ve already spent $75 on a new part.

[StanW]

You sure that's a 4 stroke engine ? From what I gather the air gap between the ignition module and flywheel magnet surface should be 0.008 to 0.012 inch.

[zoogor]

thats what im getting stan is .008. i do know its a very shot gap so id say its worth a try. and yes, the 825R is 4-stroke.

[StanW]

Ok - I have a 700 series ryobi trimmer and that hummer is 2 stroke .

[Terryl]

You sure that's a 4 stroke engine ? From what I gather the air gap between the ignition module and flywheel magnet surface should be 0.008 to 0.012 inch.

Runs on regular gas, no oil to add, says 4 stroke on the side.

Thanks for the info Stan, will go dig out the feeler gauges and reset the spacing to .010, right in between.

[anyonomus]

Runs on regular gas, no oil to add, says 4 stroke on the side.

Thanks for the info Stan, will go dig out the feeler gauges and reset the spacing to .010, right in between.

"Brass" feeler gauges I can only assume????
Magneto= magnet

[Terryl]

I have good stainless steel gauges that's all that's in the tool kit, I have wire gauges, they wont stick as bad, if it comes down to it I can pound down some copper wire to the desired thickness, or look around the shop for some brass shim stock at the right gauge.

The bad part about all this is that you have to tear it all apart to get to this section (8 screws), it would have been easier if they had made a service cover to get to this.

[Terryl]

OK guys I got it running………………..

After several attempts to start it, it fired up, but it wouldn’t run after I took it off the choke setting, after tearing it apart several thousand times and checking everything under the sun and in and out of the book I was going to go out and shoot it with my .44 magnum.

But after thinking about should I waste a .44 slug on it and looking on the work bench I came to a conclusion that maybe why it won’t run after I take it off the choke position is that it may be getting too much air with out the air filter installed.

After re-installing the air filter it ran better but would stall out, so after cleaning out the air filter it ran a bit worst and still stalled out, so after looking for the .44 mag shells I came to another conclusion that maybe why the air filter was all oily was that it needed to be oiled.

So I oiled it up and it ran a bit better, Hummmmm why does it still stall out I wondered, so after looking in the manual it says to re-oil the air filter (would have saved some time and hair if I read the manual) (but guys don’t read manuals) with 30W motor oil, I look on the work bench at the can of 3 in 1 and think could that really be it?

So after soaking the air filter in some motor oil it ran much better but after about 15 minutes it stalled out, looking for the target stand I came across some 30W motor oil (I used 5W-50) could that be the real problem?

So I washed out the 5W-50 and soaked the filter in true 30W, it started and ran great.

I will have to tackle the weeds tomorrow as I now have too many beers in me to do a good job.

In short, if it doesn’t start the first time read the manual.

Or maybe I’m getting too old for this and should have taken it to someone that works on these things.

[StanW]

Sounds to me like you have to look at the carb ; the low idle jet and the float . You didn't touch the reeds did you ?

[anyonomus]

Sounds to me like you have to look at the carb ; the low idle jet and the float . You didn't touch the reeds did you ?


Low idle jet and float I agree with..
Reeds??? they are only in a two stroke from what I can remember..
a four stroke as far as I know would have valves..intake and exhaust no matter how small the engine..

[StanW]

Right you are Any on the reeds .... old fashioned 2 stroke guy I am .lol

[Terryl]

Carb is a one piece plastic thingy, I cleaned it up and checked all screws and bolts, but this is California they don't trust us out here for adjusting anything that has to do with a carb, this thing is all sealed up with out any way to adjust anything..

Runs great with 30W in the foam air cleaner.

Or was it the sight of the .44 mag that scared the gremlins out of it?

[JCO]

Carb is a one piece plastic thingy, I cleaned it up and checked all screws and bolts, but this is California they don't trust us out here for adjusting anything that has to do with a carb, this thing is all sealed up with out any way to adjust anything..

Runs great with 30W in the foam air cleaner.

Or was it the sight of the .44 mag that scared the gremlins out of it?

It was because your filter wasnt oiled with the proper oil.. Same thing happens with K&N air filters if you dont use their oil the filter messes up the air mix and it stalls..
Theres a reason for them specifying 30W it doesnt change its viscocity with a slight temperature change.. And it has a carb??? not fuel injection??? Get with the time terryl...LOL

[superbee]

to set the air gap i just use a business card sounds like the carb is starving for fuel check fuel filter and screen in carb