photos taken from cylinder show buildups of something that seems to be carbon, if I rasp it with a screwdriver i can see that there is still polished chrome under it, but correct me if im wrong Im not skilled on this matter... trying to learn reading...
Chinese engine failure after 1300 miles - Tried troubleshooting root cause unknown -
- Thread starter djsalto
- Start date
chrisnbush
Member
Just some thoughts -
I started losing power at 2500 miles on my first DAX. I pulled the piston, and the lower bearings were failing - the connecting rod wobbled quite a bit on the lower bearing.
Any of these motors I have pulled, the piston is always pretty loosey goosey on the top bearings, even on a new engine. You might want to take the pin out of the piston (remove clip on side) and check pin - is their a groove worn in it ? Are the bearings missing a roller ?
My first motor lost power at higher speeds , and I learned about the intake gasket. It must be air tight, these things will suck air like crazy. I have extras, but have had real good luck with one on my current motor (DAX) that I made out of a margarine box (that waxed cardboard) - I learned this from a post.
I have 3400 logged miles on my current DAX. I have never run it at full throttle though, and pretty much always pull the clutch and coast down hills - even small ones. My crusing speed is like 23 miles per hour. I got a 44 tooth sprocket, and use 20:1 oil that I get at Walmart by the gallon. This is my transportation, so I go easy on it.
Not that I don't want to go fast, but if you wind these things up going DOWN hill you are asking for trouble.
I am thinking your bearings are going, wiggle the connecting rod, should be tight and check the top ones. By the way, you can go to a chainsaw store and get Stihl 028 wrist pin bearings, these are supposed to work as upper bearing replacements - I have never had occassion to try them, but I bought them and they fit.
Otherwise:
1st engine I got 1500 miles, from LFM or some vendor like that - top bearings went and motor locked up
2nd engine from DAX, blew up (top bearings again) after 400 miles, DAX sent me replacement under warranty
3rd engine (DAX replacement) got 2500 miles (still running but big loss in power, bottom bearings going)
4th engine used from eBay for 60 bucks was real weak, I think the kid screwed up the ports with a dremel and wanted to unload it - I trashed it.
5th and current engine 3400 miles - seems to be running strong - a small loss in compression maybe over time, but not much. I put on an angle fire head for more juice.
I could rebuild the current one maybe, but the "aint broke don't fix it" applies to me
Your pics seem to indicate more wear on your motor than I would expect with that few miles. So again, I suspect the bearings.
I started losing power at 2500 miles on my first DAX. I pulled the piston, and the lower bearings were failing - the connecting rod wobbled quite a bit on the lower bearing.
Any of these motors I have pulled, the piston is always pretty loosey goosey on the top bearings, even on a new engine. You might want to take the pin out of the piston (remove clip on side) and check pin - is their a groove worn in it ? Are the bearings missing a roller ?
My first motor lost power at higher speeds , and I learned about the intake gasket. It must be air tight, these things will suck air like crazy. I have extras, but have had real good luck with one on my current motor (DAX) that I made out of a margarine box (that waxed cardboard) - I learned this from a post.
I have 3400 logged miles on my current DAX. I have never run it at full throttle though, and pretty much always pull the clutch and coast down hills - even small ones. My crusing speed is like 23 miles per hour. I got a 44 tooth sprocket, and use 20:1 oil that I get at Walmart by the gallon. This is my transportation, so I go easy on it.
Not that I don't want to go fast, but if you wind these things up going DOWN hill you are asking for trouble.
I am thinking your bearings are going, wiggle the connecting rod, should be tight and check the top ones. By the way, you can go to a chainsaw store and get Stihl 028 wrist pin bearings, these are supposed to work as upper bearing replacements - I have never had occassion to try them, but I bought them and they fit.
Otherwise:
1st engine I got 1500 miles, from LFM or some vendor like that - top bearings went and motor locked up
2nd engine from DAX, blew up (top bearings again) after 400 miles, DAX sent me replacement under warranty
3rd engine (DAX replacement) got 2500 miles (still running but big loss in power, bottom bearings going)
4th engine used from eBay for 60 bucks was real weak, I think the kid screwed up the ports with a dremel and wanted to unload it - I trashed it.
5th and current engine 3400 miles - seems to be running strong - a small loss in compression maybe over time, but not much. I put on an angle fire head for more juice.
I could rebuild the current one maybe, but the "aint broke don't fix it" applies to me
Your pics seem to indicate more wear on your motor than I would expect with that few miles. So again, I suspect the bearings.
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Now engine is working and on break-in just replaced cylinder, piston and rings (with upper connecting rod)
engine is running ok, just little worried because i hear a noise like a bell i think maybe a bad bearing but on the bigger end of the connecting rod.
Suggestions?
Thanks all of you guys for your help
engine is running ok, just little worried because i hear a noise like a bell i think maybe a bad bearing but on the bigger end of the connecting rod.
Suggestions?
Thanks all of you guys for your help
Last edited:
well god ****.. , you guys are only getting about 600-3000 miles out of these things?
And went through 5 engines already?
****!!!
So if each engine is $100, after $1500, you could only get about 15000 miles if each engine got 1000 miles a piece?
WTF!
I mean ****. So thats the life expectancy of these things......, ****.
Im now thinking about selling mine now when I fix it up.
And went through 5 engines already?
****!!!
So if each engine is $100, after $1500, you could only get about 15000 miles if each engine got 1000 miles a piece?
WTF!
I mean ****. So thats the life expectancy of these things......, ****.
Im now thinking about selling mine now when I fix it up.
HeadSmess
Well-Known Member
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well god ****.. , you guys are only getting about 600-3000 miles out of these things?
And went through 5 engines already?
****!!!
So if each engine is $100, after $1500, you could only get about 15000 miles if each engine got 1000 miles a piece?
WTF!
I mean ****. So thats the life expectancy of these things......, ****.
Im now thinking about selling mine now when I fix it up.
that was a highly articulate outburst! though also ignorantchrisnbush
Member
Well, you have to think a little about the value of the motors. The total MONEY I spent on motors since the fall for 2007 is 120 x 2 (two new kits), 100 (one replacement motor), 60 (I used motor I wanted to play with) = $400 total cost.
I got a total of 7800 miles on motors (see above). I have a jeep that gets 20 miles per gallon, if I had driven that (my only other ride) would have used 7800/20=390 gallons of gas. At $2.80 per gallon (it has been much higher than that since 07) that is $1092 dollars. I get 80+ MPG on my bike (LOTS of hills), since the gas mileage is 4x better, that would be 1092/4 = $273. SO my savings taking my bike (I commute 30 miles a day) has been 1092-273 = $819.
So $819 gas savings - $400 equipment cost = $419 profit. I have certainly spent that on parts, mirrors, oil to mix with gas (Walmart cheapo 2 cycle in quantity) BUT think of the savings for brakes, tires, etc. on the Jeep. I can't replace the tires on the Jeep for less than $400 and that is for the 2 year wear max life tires ! And oil changes, etc.
I have another 4 cycle bike that I have used since 08, got over 3000 on it - probably have just about paid for it at this point.
The reasons I am moving away from 2 cycle is, kind of strangely as I have done so much work on them and have gotten them to be pretty reliable for me, is the oil mix (!). I work in an office, and the extra oil (in the gas) makes the engine dirty quickly, frame, tires, etc. Every time I touch the dang thing I ruin another shirt or pair of pants. Also, my feeling at this point is that the Hua Sheng motor is going to get more miles on it than your average 2 stroke motor. Since I commute a reasonable distance, I think I am going to save even more with the 4 stroke.
I have a Titan motor now on a moondog, center mounted, using the Grubee 4g transmission (the one with the freewheel). Have about 400 now on this situation, this is the Titan motor that I have over 3000 miles on. I hear that the freewheel can be a problem, might consider replacing it with a fixed sprocket, until then I will get and keep a spare with me. Not quite as much speed as the 2 stroke, but pretty good torque (have it geared low). Better for my purposes - I am going for the best value. I drive the thing much of the winter time.
As I read a lot on this and other forums, its all about what you like and what you are trying to accomplish. The other thing is how much I enjoy riding my motorized bike. I love it - it is different than a motorcycle (had a number over the years), just great !
Enjoy the ride, and remember how much you enjoy it when you are working thru technical problems. It gets better (at least it has for me)
I got a total of 7800 miles on motors (see above). I have a jeep that gets 20 miles per gallon, if I had driven that (my only other ride) would have used 7800/20=390 gallons of gas. At $2.80 per gallon (it has been much higher than that since 07) that is $1092 dollars. I get 80+ MPG on my bike (LOTS of hills), since the gas mileage is 4x better, that would be 1092/4 = $273. SO my savings taking my bike (I commute 30 miles a day) has been 1092-273 = $819.
So $819 gas savings - $400 equipment cost = $419 profit. I have certainly spent that on parts, mirrors, oil to mix with gas (Walmart cheapo 2 cycle in quantity) BUT think of the savings for brakes, tires, etc. on the Jeep. I can't replace the tires on the Jeep for less than $400 and that is for the 2 year wear max life tires ! And oil changes, etc.
I have another 4 cycle bike that I have used since 08, got over 3000 on it - probably have just about paid for it at this point.
The reasons I am moving away from 2 cycle is, kind of strangely as I have done so much work on them and have gotten them to be pretty reliable for me, is the oil mix (!). I work in an office, and the extra oil (in the gas) makes the engine dirty quickly, frame, tires, etc. Every time I touch the dang thing I ruin another shirt or pair of pants. Also, my feeling at this point is that the Hua Sheng motor is going to get more miles on it than your average 2 stroke motor. Since I commute a reasonable distance, I think I am going to save even more with the 4 stroke.
I have a Titan motor now on a moondog, center mounted, using the Grubee 4g transmission (the one with the freewheel). Have about 400 now on this situation, this is the Titan motor that I have over 3000 miles on. I hear that the freewheel can be a problem, might consider replacing it with a fixed sprocket, until then I will get and keep a spare with me. Not quite as much speed as the 2 stroke, but pretty good torque (have it geared low). Better for my purposes - I am going for the best value. I drive the thing much of the winter time.
As I read a lot on this and other forums, its all about what you like and what you are trying to accomplish. The other thing is how much I enjoy riding my motorized bike. I love it - it is different than a motorcycle (had a number over the years), just great !
Enjoy the ride, and remember how much you enjoy it when you are working thru technical problems. It gets better (at least it has for me)
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