7hp Subaru Robin Puffs white smoke.

[j.concepcion54321]

Well im having a problem with my subie engine. Its currently on my manco 415 2 seater kart. Well the other day i was riding when it started puffing out these huge white plumes of smokke. And then it shut off. i rolled it into the back and saw that the oil was black so i changed the oil hoping that would fix the problem. It did at first. So i thought i was all set...

Today i went to ride it and after doing a few laps around my street the same thing started hapening, but this time it puffed out a **** load of smoke. like 10 times more thatn before. and so i shut it off, but even after it was off it kept smoking for a little while...

What could be the cause? I havent checked the oil again yet but i doubt that is the problem... Any thoughts? Also it smells like it is burning oil.

One more thing, the exhaust im using isnt meant for this engine so its a little offset, but it still cover the exhaust port fully so i dont think its a problem, what do you guys think? could this be a problem?

Thanks

 

[j.concepcion54321]

Heres a pic of the exhaust...

 

[jernigan]

I've fixed a few engines that were doing the same thing. A cloged breather would be the first thing i would check. It could also be worn or damaged valve stems or a broken piston ring.

 

[j.concepcion54321]

Hey, whats the breather? also how would i be able to know if its the valve stems or the piston rings?

 

[r97]

The breather is a vent leading into the air-box that allows the engine to keep the crank case pressure constant, and equalized with the external air pressure.

If i remember correctly, white smoke indicates fuel vapor that was not combusted in the engine. Right now I am thinking that maybe your problem is caused by an exhaust that isn't sealing, bad float, needle, stuck choke, or clogged air filter. Also, the muffler is likely not sealing correctly, allowing the problem to be more noticeable.

Wait for Russ to come around, he should be able to sort this out much faster than i could. One thing I can tell you for sure though is that that exhaust is just asking for trouble, at the least your risking shearing the mounting studs.

P.S. Blue smoke indicates oil being burned, often caused by worn piston rings, or valve guides.

 

[j.concepcion54321]

ok so what are the things that i should do? check the exhaust to see if its dirty, clean the airfilter, check the breather and see if the problem persists?

 

[jernigan]

Sorry i didn't answer back, I've been out of town for a couple of days. usually when there is "white" smoke coming from the exhaust there is water getting into the combustion chamber. But this being a 7HP air cooled engine, if there was that much water in the fuel it probably wouldn't run at all. If it was flooding (to much fuel entering the combustion chamber) you would be getting puffs of black smoke with a strong gasoline smell. So I am "assuming" you are burning oil. P.S. How long have you had that exhaust on that engine. It's possible that if you got it off of an engine that was worn or sit up outside that it could be full of gunk.

 

[Russ2251]

White smoke always indicates an oil control problem.

 

[sexyvicta]

^you can get white smoke from very stale petrol.

But if it smells like oil then its oil

 

[Russ2251]

Never witnessed that. Black is what I've seen. Resembles a rich condition, or incomplete combustion.

 

[jernigan]

White smoke is a new one to me on a small engine. I only ever seen it one time. An old timer showed me a little trick on cleaning carbon out of the engine. Dribble a little breakfluid in the carb while it is running. It worked, but there was the most white smoke I had ever seen in my life.

 

[j.concepcion54321]

i think i have a pic somewhere of the engine smoking. Ill check the exhaust and see if its full of gunk tomorrow, ill also check my oil to see what thats like, and ill try some new gas. Ill let you know my results. Could it be that i didnt use enought oil when i changed it? should i add some more to check?

Thanks guys, im really liking all this help

 

[j.concepcion54321]

ok well i took off the exhaust and it had some oil in it. also the surrounding area had some oil. So then i took off the carb, and that had oil in it too!! i know thats not a good sign. i also saw that where the carb goes that had some oil too. So i think that it is an oil control problem. I was considering bringing it to an engine shop to have it looked at and fixed but i dont have any dough to do it. so i took the carb off and adapted it to my clone engine and it runs now... kinda. so im still stuck as to what to do. i really wanna just fix the subie, or just get a new engine. im done dealing with this stuff. i just want something that runs and i can rely on. so far my briggs is the best engine ive had and thats on my bros kart.

i have the subie, a 5.5hp clone(i must add its in very bad shape, definitely beaten alot and i think the engine got dropped or something, the crankcase is bent, so is the recoil, and i think the flywheel is missing some fins.) and 2 tecumsehs. both 5 horse one is ohv the other is a flatty.

Which one will i have the least trouble with?

 

[HellSpawn]

Make sure you didn't overfill the thing with oil. Can cause giant plumes of white smoke if the engine is tilted at various angles with too much oil in it.

 

[j.concepcion54321]

I tried removing oil already and it didn't do anything. The thing is when I first turn it on its fine, then when I ride halfway up my street it starts smoking like a mofo and then it shuts off

 

[r97]

You sure you didn't run 2 stroke oil mix through the system? That could explain a lot.

In my opinion (who would guess this) I think you should go with the Subaru. Once running correctly it will run like a champ and take whatever you throw at it.

 

[kendelrk]

what you could do is drain all oil, pull off the side cover and put saran wrap over it, fill with some oil and turn the crank multiple times and dertermine where the oil is coming from, if nothing happens it might just be from sitting, i had one that if i let it sit over 2 weeks without running, it would spit smoke for the day, but next day it was fine

 

[j.concepcion54321]

Ok we'll. I drained out all the oil, went to the subaru website and found out the correct amount it needs and put that in. And then I ran it and now its just steady smoke. Its not just whenn I rev it up high. I turn it on and it smokes, I turn it off and it keeps smoking a lil. I think I need to try cleaning out the exhaust. For now I just put the subie on my minibike. I honestly don't mind the smoke if its not damaging the engine. I'm going to make an exhaust with a straight pipe so that I don't damage the threads for the exhaust and stuff.

What other tips can you guys give me that don't involve taking it apart? I haven't checked for the stale gas thing,m should I try that?

 

[kendelrk]

well, take off the exaughst pipe and run it without that for a second and see if it smokes, it might just be **** in the exaughst, or **** in the port, and see if it gets worse as you rev it up, or if it goes away

 

[j.concepcion54321]

Ill try it when I get a chance. Lol Ill have to wear safett goggles in case it starts puking out oil. Lol