4 stroke hasn't started in over a year

artmaker

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Ok, since my previous threads are so old, will start all over.
I have a Huasheng 4 stroke (improvement over my old 2 stroke) that has given me fits since I got the thing.
I'll post a list of all I did so far below,
short question first.... I THINK I narrowed down the issue to a bad kill switch. Actually I have two of them.
One on the hand grip gave out a year before the thing quit starting, and I've been using the little red button on the side of the motor.
The last time this bike ran, (summer before last) it was running like crap. Nowhere near the power it once had, hard to start... then on Memorial day, first time I started the bike that year, it was a royal pain just to get started. Ran real rough, very short trip, basically just rode a few blocks around my house, and even harder to restart later.... then tried for a late night ride and it simply would NOT start at all.
A friend helped me sort this out using a spark plug tester, and told me that yes, if the kill switch is going bad, it could have been causing all the crappy engine running issues until it just flat out fried. After we disconnected it and tried, at least now the motor sounds like it's trying to fire... (next thing to do is replace the two year old gas and try again.)
So... snooping around online... where the blazes does one find a new kill switch? Also could my having two of them, one on the motor and one on the hand grip have been a problem? I would rather lose the one on the motor and keep the one easier to grab if I have a choice. Or does that even matter.
So any advice on this would be appreciated....


Now for all those interested, the history of my nightmare with this motor.

First, the guy I bought it from sold me his own hand made clutch cover.... which was a hugely bad idea. Piece of cheap tin that awkwardly attached over the clutch, and did NOT seal it.... so every manner of grit and oily crud got right into the clutch, not even one year into this I had to buy a new, closed clutch box, also put in a heavy duty clutch, all of which needed a new chain, different gear ratio. Big pain.

Good for one season, the next started with the hard to start and running kinda rough issues.
First order of business was cleaning the carb. Did that twice, nothing. Replaced it. Also put in a better spark plug... nope.
Someone said adjust the valves, learned about that, bought the gauge, got er done. Got it running BUT....
I must have just got lucky, did not know about finding top dead center. But that got me a season.
Next year was the last time it ran at all. And this time I did not get lucky, read up on finding top dead center, and I STILL can't quite get that one.
Stick a straw into the spark plug hole, turn the engine over and the straw goes up down up down... great. It's a FOUR stroke. Up down up down. WHICH UP IS THE RIGHT UP???? That one I don't know.
Had a mechanic friend look, and HE set it to just the right spot.... (without actually showing me how he knew, and he vanished after this.) I did my adjustments, and still... nothing. Got frustrated and the bike sat ever since. (built another one instead.)

So now... another friend is the one who tried testing for spark and figured out it might just be this kill switch, the test light did light but just barely, then we removed the kill switch and it did light. Hence, it just might be that simple. Faulty kill switch. (again, still not starting but I have yet to flush out the old fuel. I will need some kind of kill switch, may as well get that first.)
And that's where I stand to date.

OH... Also... my exhaust pipe had to be bent to fit my frame, had a friend with a good vice and torch help bend it. That had to be done right away when I first got this motor and it's has run with it, but there is a point in the pipe that got just a bit crimped. I'm guessing here, but at one point the inside of the pipe may be 3/4 the diameter of the rest. I'm wondering if that might have clogged? Or even if just being slightly crimped if it may have over heated the motor and ruined it, and if so is there any way to open the motor up and see? What do you look for in an over heated motor? And if I have to replace the exhaust I think what I'll do is take the old one, and a new one to an exhaust shop and have THEM bend it. Just say match this shape but without the kink. Hope I can find a place that will work on such a skinny pipe. Shops might only have equipment to do car exhausts.

Anyway... kill switches, preferably hand grip only, where to find one.
thanks.

Bike4stroke.jpg

 
On the TDC stroke at TDC both the valves will be a little loose with play in them. There's a black plastic jet located under the black plastic idle adjustment screw. You remove it by gently twisting it and pulling up at the same time. On the bottom is a brass jet that is very tiny to clean. I've used a fine wire from a metal brush to push through it. Also there's 1 or 2 orings that seal that bugger, both need to be pliable and seal. If they don't seal it can cause issues especially no increase in throttle response, stumbling etc.. Don't remember if there's 1 or 2 orings but just pay attention when pulling it apart. You can't buy that jet if you bugger it up anywhere so try and be careful. You can buy the jet from ereplacement parts using the Honda GXH50 motor/carb and it works. Compare that price to a HS 142F on fleabay and decide which is better choice.
 
Ok, since my previous threads are so old, will start all over.
I have a Huasheng 4 stroke (improvement over my old 2 stroke) that has given me fits since I got the thing.
I'll post a list of all I did so far below,
short question first.... I THINK I narrowed down the issue to a bad kill switch. Actually I have two of them.
One on the hand grip gave out a year before the thing quit starting, and I've been using the little red button on the side of the motor.
The last time this bike ran, (summer before last) it was running like crap. Nowhere near the power it once had, hard to start... then on Memorial day, first time I started the bike that year, it was a royal pain just to get started. Ran real rough, very short trip, basically just rode a few blocks around my house, and even harder to restart later.... then tried for a late night ride and it simply would NOT start at all.
A friend helped me sort this out using a spark plug tester, and told me that yes, if the kill switch is going bad, it could have been causing all the crappy engine running issues until it just flat out fried. After we disconnected it and tried, at least now the motor sounds like it's trying to fire... (next thing to do is replace the two year old gas and try again.)
So... snooping around online... where the blazes does one find a new kill switch? Also could my having two of them, one on the motor and one on the hand grip have been a problem? I would rather lose the one on the motor and keep the one easier to grab if I have a choice. Or does that even matter.
So any advice on this would be appreciated....


Now for all those interested, the history of my nightmare with this motor.

First, the guy I bought it from sold me his own hand made clutch cover.... which was a hugely bad idea. Piece of cheap tin that awkwardly attached over the clutch, and did NOT seal it.... so every manner of grit and oily crud got right into the clutch, not even one year into this I had to buy a new, closed clutch box, also put in a heavy duty clutch, all of which needed a new chain, different gear ratio. Big pain.

Good for one season, the next started with the hard to start and running kinda rough issues.
First order of business was cleaning the carb. Did that twice, nothing. Replaced it. Also put in a better spark plug... nope.
Someone said adjust the valves, learned about that, bought the gauge, got er done. Got it running BUT....
I must have just got lucky, did not know about finding top dead center. But that got me a season.
Next year was the last time it ran at all. And this time I did not get lucky, read up on finding top dead center, and I STILL can't quite get that one.
Stick a straw into the spark plug hole, turn the engine over and the straw goes up down up down... great. It's a FOUR stroke. Up down up down. WHICH UP IS THE RIGHT UP???? That one I don't know.
Had a mechanic friend look, and HE set it to just the right spot.... (without actually showing me how he knew, and he vanished after this.) I did my adjustments, and still... nothing. Got frustrated and the bike sat ever since. (built another one instead.)

So now... another friend is the one who tried testing for spark and figured out it might just be this kill switch, the test light did light but just barely, then we removed the kill switch and it did light. Hence, it just might be that simple. Faulty kill switch. (again, still not starting but I have yet to flush out the old fuel. I will need some kind of kill switch, may as well get that first.)
And that's where I stand to date.

OH... Also... my exhaust pipe had to be bent to fit my frame, had a friend with a good vice and torch help bend it. That had to be done right away when I first got this motor and it's has run with it, but there is a point in the pipe that got just a bit crimped. I'm guessing here, but at one point the inside of the pipe may be 3/4 the diameter of the rest. I'm wondering if that might have clogged? Or even if just being slightly crimped if it may have over heated the motor and ruined it, and if so is there any way to open the motor up and see? What do you look for in an over heated motor? And if I have to replace the exhaust I think what I'll do is take the old one, and a new one to an exhaust shop and have THEM bend it. Just say match this shape but without the kink. Hope I can find a place that will work on such a skinny pipe. Shops might only have equipment to do car exhausts.

Anyway... kill switches, preferably hand grip only, where to find

Stop playing the guessing game. When it comes to valve adjustments you need the proper tools. If somebody doesn't bring the proper tools to do the job with. You should then began to question their qualifications.

Thread 'Robin Subaru EH 035 Valve Adjustments' https://motoredbikes.com/threads/robin-subaru-eh-035-valve-adjustments.57938/

Any engine that had set up for a year needs a good Sea Foam flushing.

If you know you're going to be storing the bike for a lengthy period, drain the gas and let the engine run till it cuts off. Spray the inside of the carb with Sea Foam. Drain the oil and flush the pan with Sea Foam. I then like to fill the cylinder head with Sea Foam through the spark plug hole and fill the oil pan with Sea Foam. Get a vacuum pump it makes doing this very easy. Then when you're ready to ride again all you have to do is pump the Sea Foam out and replace it with oil in the pan and put gas in your tank.

Get a tachometer/hour counter. Change the oil every 25 hours of use and clean the air filter every 10 hours of use. My Robin Subaru 35 is 11 years old and still working great. All I've ever replaced is the spark plug and the carburetor.
 
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Adjusting the valves really isn't hard. I did it when I took my engine off the old frame. As long as you have a few allen wrenches/torx bits an 8mm box wrench and feeler gauges a monkey's uncle could do it. Like you said a straw or bic pen can help find tdc it's when the magnet is closest to the coil and check with an LED flashlight. Before you see the piston start going down in the bore that's where you adjust it. Mine wasn't the killswitch or the valves being a problem but the whole rear wheel because stock huffy wheels are crap and the clutch being the crap ebay one. Probably has several hundred miles on the engine maybe 600-800 miles. Some 2 strokes will have mechanical engine problems by then so I view the engine as alright. It would be cool to see 40mph out of one of these little 49cc engines.
 
Ok, all the replies here are great. I'll address a few,
1. been watching more videos on valve adjustments.... I sure can try that again.
2. Seafoam.... never heard of the stuff but.... my friend already told me to pick up some lucas fuel injector cleaner.... found at least one youtube vid comparing the two and lucas came up better. Either way yes I'll grab a can.
3. Clutch I already addressed..... already had to basically rebuild mine on year one. Only because the moron who sold me this took OFF the original all enclosed clutch that was suppose to come with this motor and slapped on his own. But when I replaced the whole thing, being a heavy person to begin with I bought heavy duty parts.... it's not the clutch. I can't get the thing STARTED....
>>> which circles back to the use of seafoam OR lucas.... watching videos, one has to run the motor with the stuff in it. IT WILL NOT START so how can I "run the motor" with cleaner inside?


Finally...... guys. We TESTED THIS. When the kill switch is completely disconnected, we got a flash from the tester showing there would be spark. When the kill switch was wired up, there was a light but very dim. So I'm back to the one thing I have not yet changed out, the stupid kill button. And where to find one? Can I have two? One on the motor and one on the handgrip? Or do they conflict?
 
I'd adjust the coil when it is over the magnets on the flywheel with a regular business card and use just the handlebar killswitch. Take off the wires that you spliced in or whatever. Could be a bad coil, inspect the wires for anywhere it could be touching metal or bare wire.
 
On the TDC stroke at TDC both the valves will be a little loose with play in them. There's a black plastic jet located under the black plastic idle adjustment screw. You remove it by gently twisting it and pulling up at the same time. On the bottom is a brass jet that is very tiny to clean. I've used a fine wire from a metal brush to push through it. Also there's 1 or 2 orings that seal that bugger, both need to be pliable and seal. If they don't seal it can cause issues especially no increase in throttle response, stumbling etc.. Don't remember if there's 1 or 2 orings but just pay attention when pulling it apart. You can't buy that jet if you bugger it up anywhere so try and be careful. You can buy the jet from ereplacement parts using the Honda GXH50 motor/carb and it works. Compare that price to a HS 142F on fleabay and decide which is better choice.
I don't know if the running issue is related to that piece in the carb. Mine still has it and it starts up 2nd or 3rd pull. It does hesitate to take throttle slightly but I was thinking of using a delorto clone. Problem is all the offset intakes are for 2 strokes.
 
Ok, all the replies here are great. I'll address a few,
1. been watching more videos on valve adjustments.... I sure can try that again.
2. Seafoam.... never heard of the stuff but.... my friend already told me to pick up some lucas fuel injector cleaner.... found at least one youtube vid comparing the two and lucas came up better. Either way yes I'll grab a can.
3. Clutch I already addressed..... already had to basically rebuild mine on year one. Only because the moron who sold me this took OFF the original all enclosed clutch that was suppose to come with this motor and slapped on his own. But when I replaced the whole thing, being a heavy person to begin with I bought heavy duty parts.... it's not the clutch. I can't get the thing STARTED....
>>> which circles back to the use of seafoam OR lucas.... watching videos, one has to run the motor with the stuff in it. IT WILL NOT START so how can I "run the motor" with cleaner inside?


Finally...... guys. We TESTED THIS. When the kill switch is completely disconnected, we got a flash from the tester showing there would be spark. When the kill switch was wired up, there was a light but very dim. So I'm back to the one thing I have not yet changed out, the stupid kill button. And where to find one? Can I have two? One on the motor and one on the handgrip? Or do they conflict?
I've never used more than one kill switch. Sea Foam is small engine repair tech's goto product for keeping engines cleaned out. I strongly suggest getting a top dead center tool; they're very inexpensive usually under $20. The TDC tool has a scale on it so you have a reference point. It is also holding the measuring scale in the dead center of the spark plug hole. Though you may be close using the ink pen or straw method, it is at best still a guess. Unfortunately, being close isn't good enough. Being as little as 1mm off can keep the valve timing from performing at peek performance.

If you have feeler gauges to adjust the valves with; then also use them to adjust the coil spacing with. Unless you use a feeler gauge calibrating tool on the card you have no way of knowing how thick the card is.
 
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So started shopping for a TDS tool. GOOD LORD!!!!! Called O'reilly's, guy didn't even know what I was talking about. (unusual for them.) Tried Autozone, all they show is some gadget with long wires on it, not what I need I'm sure.
Tried just shopping online.... the plethora of devices blows my mind! Found the exact one pictured in this thread on ebay SOLD IN PAIRS! I don't need TWO of them.

And STILL no leads on a kill button?
I swear I'm about ready to just buy a new motor and chuck this POS. Except without knowing what went wrong, it may do the same thing.
grrrrrrr.
 
I really wish at this point I could find a good mechanic willing to take on a side job and not only fix this thing but show me what was wrong. Finding a good mechanic though..... about as easy as finding a good doctor. (I have yet to land one in that department either.)
 
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