hs50 questions

kai20

New Member
#1
My dad has an old mini bike with an HS50 67005 engine, and I recently did I rebuild as a school project but never got it to start. Quite honestly I am pretty inexperienced overall with small engine mechanics.

1. Is the carb supposed to be slanted? It does not lay perfectly flat as you’d expect for a carb.

2. What are some possible issues as to why it won’t start? It has spark, and it has gotten very close to turning over a few times.

I want to try and figure it out without having to bring it into a shop, so any advice overall is appreciated.
 
#4
With that carb intake your engine is meant to be installed on a slanted engine mounting plate. Once the engine is installed the carb bowl will be level. Does the bike you are putting it on have a slanted or level engine mounting plate?
Michael
 

kai20

New Member
#5
With that carb intake your engine is meant to be installed on a slanted engine mounting plate. Once the engine is installed the carb bowl will be level. Does the bike you are putting it on have a slanted or level engine mounting plate?
Michael
After checking yes it does, thank you.
 
#7
As part of your recent "rebuild"did you (completely) disassemble and (thoroughly) clean the carb? If "yes", by what procedure did you use? Do you have the low and high speed jets/needles set properly?
Michael
 

kai20

New Member
#8
As part of your recent "rebuild"did you (completely) disassemble and (thoroughly) clean the carb? If "yes", by what procedure did you use? Do you have the low and high speed jets/needles set properly?
Michael
No not really. We took apart most of the exterior parts and somewhat cleaned it. That was the only part we didn’t thoroughly clean besides the exhaust.
 

kai20

New Member
#9
Setting/adjusting the timing can be a challenge on those. Are you confident you got that right?
Yes pretty confident, all of the timing marks and such were still very visible and we checked to make sure the valves moved at the correct times as well as the piston.
 

Triley41395

Well-Known Member
#11
Yes pretty confident, all of the timing marks and such were still very visible and we checked to make sure the valves moved at the correct times as well as the piston.
You said that you rebuilt it for a school project, do you know if it ran before the rebuild? I'm guessing it didn't run before and that's why you done the rebuild. Have you tried starting fluid? If you have not tried starting fluid try that and if it starts on fluid it is most likely the carb.
 
#12
No not really. We took apart most of the exterior parts and somewhat cleaned it. That was the only part we didn’t thoroughly clean besides the exhaust.
Soooooo....
The "rebuild" you did was just removing the exterior parts and cleaning them? Not trying to be a PITA- just need to be clear on what you have already done to the engine so that we can help you moving forward...
Michael
 
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f4radar

Well-Known Member
#15
Are those before your rebuild or after pictures. If after; that motor does'nt look in any condition to test run. You should probably put a new spark plug on it. I’ve had plugs that spark but won’t run motor. You should also double check your points and timing. That said your carburetor is also going to be a main source of problem. You might be better off to get a cheap Chinese clone at least to get it running in the first place.
 
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kai20

New Member
#16
You said that you rebuilt it for a school project, do you know if it ran before the rebuild? I'm guessing it didn't run before and that's why you done the rebuild. Have you tried starting fluid? If you have not tried starting fluid try that and if it starts on fluid it is most likely the carb.
It ran when it was parked but it’s been parked for over a decade and because of that it didn’t run before I took it apart. I will try starting fluid next time I get a chance.
 

kai20

New Member
#17
Soooooo....
The "rebuild" you did was just removing the exterior parts and cleaning them? Not trying to be a PITA- just need to be clear on what you have already done to the engine so that we can help you moving forward...
Michael
Sorry I worded that bad, I fully disassembled it as and inspected and cleaned everything as well as honing the cylinder & replacing all of the gaskets. That being said I am an amateur and was under a short time frame.
 
#20
Thank you, when I get a chance I will do it again because there is a chance I did it wrong. Do you know anywhere I could possible find a new part, the wires and other small parts aren’t in the best shape after sitting for a very long time.
Thank you, when I get a chance I will do it again because there is a chance I did it wrong. Do you know anywhere I could possible find a new part, the wires and other small parts aren’t in the best shape after sitting for a very long time.
https://www.jackssmallengines.com/jacks-parts-lookup/
 
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