Subaru Robin EX17 Problems

[l008com]

I've got a Manco Dingo with a Subaru Robin EX17 motor.

It has been running great. 1 or 2 pulls, and it starts right up. Even though its getting close to 20 years old.

So it had this little phase where, for a while, when you would shut the engine off using the little red On/Off switch, it would keep running for a while before it finally conked out. That was strange.

Then after that went on for a while, suddenly it wouldn't start. This has always been a very reliable engine. But suddenly, nothing. The exhaust smelled strongly of fuel, so I don't think it's a carb problem. I've started to wonder if the problem might be that On/Off switch? It only has one wire to it, so I'm not sure exactly how it works. But could it have broken in a way that it's not actually switching on?

An easy test might be to pull the plug, ground to the chassis and try to start, seeing if there's a spark. Unfortunately I went to ape **** crazy pulling the cord to try to start the **** thing, I snapped the rope. So I have to replace that before I can really do anything else. I wish this thing had a plug in starter like my snow blower.

So I can't actually DO anything about this right now, but I figured I'd get a conversation going now anyway. If anyone knows electrically how these switches work, and if you think that could be my problem? And if there are any thought on why it would keep running when switched off?

 

[ezcome-ezgo]

Probably a simple grounding switch. Could be bad. Can you test the continuity of the switch?

 

[OzFab]

Most likely a faulty switch; simple fix...

 

[l008com]

I hope it's a simple fix because parts for this engine are crazy expensive! Not like the $13 shipped brand new carb I got for my lawn mower! I'll order a new rope and switch and keep you posted. Hopefully the gas isn't too bad by now, I don't remember if the gas in there is stabilized or not.

 

[OzFab]

Before you pay for a new switch, why don't you see if you can clean the existing switch; just be careful of the small spring & ball bearing...

 

[anickode]

Do you check the oil every time you run it? If your carb float valve leaks even a tiny amount over time, and you don't shut the fuel off, that fuel can make its way into the cylinder and seep past the Piston rings.

I had a clone engine do that once... Over the course of a week it leaked the entire tank of gas into the crankcase.

So that could explain the gassy oil... As could the fact that it's 20 years old, and it's likely got some wear on the rings and wall.

Quickest way to tell if it's the kill switch that's the problem is to unhook it. If it runs, the switch is broken. If not, it's something else.

The running after shutting off the kill switch can also be an indication of an engine running way too hot, although that sounds more like a hit or miss engine sputtering along, with plenty of backfire.

 

[l008com]

I do not check the oil every time, I just change it once a year and thats it. But I also very rarely use this thing. These days, I usually just start it up and let it warm up from time to time and that's about it. So far I've never had any issues with the oil being bad when I change it, or the gas level going down even a bit.

That said, who said anything about gassy oil?

Wouldn't unplugging this switch PREVENT the engine from running?

I know my engine isn't running hot. It mostly just idles. I try to drive it around a bit, but then right back to idling. If I can get this thing started again, and replacing the switch doesn't solve the problem of it still running, I'll post a video.

I also have another question about this engine. It was available with three different power options, a 12 watt output, a 36 watt output, and a 200 watt output. How can I know for sure which output this engine has? I would assume it's 36 watt, because it came with an incandescent headlight, but I'd like to know for sure. I ask because at some point, I'd like to throw an LED headlight on there with some LED tail lights, and I don't want to draw more power than I'm making.

---------- Post added at 06:10 AM ---------- Previous post was at 06:08 AM ----------

Before you pay for a new switch, why don't you see if you can clean the existing switch; just be careful of the small spring & ball bearing...

The switch is one of the few parts that's not too expensive. And the current switch is getting pretty brittle from the sun, so I figure I might as well change it anyway. This way I won't have to pay shipping twice if I replace the cord, then still need to order a switch.

 

[l008com]

Bad news. I replaced the rope and the switch, but the engine still won't start. I also pulled the plug (which looked fine) and grounded it to the block. I am definitely getting spark. Smells like I'm getting plenty of fuel. Air filter is nice and clean. Not sure what's going on with this thing?? It may not be the freshest fuel in the world in there, but it's not that old. And this has always been one of those engines that will run on almost anything.

I'm open to suggestions

 

[OzFab]

Spark plug?

Remove the spark plug & repeat the spark check at the plug; remember, just because it has spark outside the engine doesn't necessarily mean it will inside the engine, it must be a strong spark...

If you feel it has a strong enough spark, refit the plug & try to start the engine, then remove the spark plug; if it's wet, it's getting fuel...

 

[l008com]

How do you judge how "strong" the spark is? I really have no idea. Also if the spark is weak, is it the plug or is it whatever part of the engine creates the electric pulse? the plug looks lightly used, but then again is a $3 plug so easy enough to replace.

 

[OzFab]

If you can hear the spark, it's strong...

 

[esfoder]

Be careful and don't ground it next to the plug hole. I saw a farmer do that and it shot a 6 foot flame out the spark plug hole when it ignited. Old John Deere 620 two cylinder. I gotta admit it was cool but the farmer just about soiled himself.

 

[l008com]

My spark didn't look that strong, so I'm trying to replace it. "trying" because I can't seem to find this plug at any auto parts store.

Also, is there a trick to getting the starter rope coiled right? I replaced my rope but it doesn't wind into the engine all the way, I'm not sure exactly how to line it up just right.

 

[OzFab]

Remove the recoil unit (not the entire shroud); you should see a notch cut in the rope "wheel"; align the notch so it lines up with the rope exit point & pull the rope up into the notch. Now turn the rope wheel a few times in the direction it would be pulled until you feel the spring tension... Done...

 

[l008com]

Ok I could not find this spark plug at any local automotive shop, so i ordered it on Amazon and threw it in today. As soon as I put it in, I pulled the cord and half a pull started it right up! While it was idling, I re-wound the pull cord and that seems to be fixed.

So the engine was idling but there seemed to be a lot of blue smoke. It idled well for a few minutes, then died suddenly. Given it hasn't been run in 6 months or so, that didn't seem too unusual. I let it sit for a while, then figured let me check the oil level to see how that looks. Theres never been any kind of oil puddle under it so i don't think it would be leaking, but good to check. And maybe it was overfilled? So I pulled the dip-stick/plug and oil gushed out of that! That makes no sense to me, but I plugged it back up fast.

At this point I'm very confused. I didn't feel like changing the oil but I have oil on hand so figured might as well. I drained it and replaced it with mobile 1 0w-30 synthetic. A little fancy for a go kart but thats what I have on hand, and that should make it easier to use/start when it's 0° out and I want to rip through some snow!

As the oil was draining, it was really glugging hard, it was almost as if there was some kind of pressure in there pushing it out. It also seemed to smell like gas a bit to me. I'm no expert on that sort of thing though. But the gas tank was still full. And when I measured what came out, it was right around 20 oz. So everything added up. I put it all back together, started it up again, and it ran great. Now it's outside idling as I type this. I want to burn through the gas that's in there so I can get some fresher (and stabilized) gas in it. It's not so old I want to drain the tank, but it's old enough that the sooner I get rid of it, the better.

So I'm not exactly sure what happened but everything seems to be running great now. The new switch has a nice solid clunk when you turn the thing on and off The pull cord is fresh and new, and the engine runs great.

I'm going to try to at least start it up once a week till the gas is gone. If it keeps working well through all that, then maybe I'll start to think about some of the upgrades I've wanted to do

 

[MTNSleder]

Turn your fuel off, gas leaks through the carburetor and through the piston rings into the oil pretty easily when gas is left on...

 

[KartFab]

Turn your fuel off, gas leaks through the carburetor and through the piston rings into the oil pretty easily when gas is left on...

...especially if you have a bad float needle or dirty carb that keeps the float needle from fitting into the seat.