79cc issues

#1
i got a 79cc with a 19mm carb and gov delete. its got spark and fuel to carb. but nothing. compression feels week. it was a new out of box engine. any help
 
#3
If it's a Predator ?
Had one of those for a couple of hrs. , & ended up taking it back to HF,, because the valves were to tight,, & the rocker arms were not centered at all over the valve stems ect.,, & couldn't get them to line up better.
It was pretty bad. :eek:

I would pull the V - cover & check that out. ;)

Added,,

Did you completely remove the governor from inside the case ??

I
 
#4
If it's a Predator ?
Had one of those for a couple of hrs. , & ended up taking it back to HF,, because the valves were to tight,, & the rocker arms were not centered at all over the valve stems ect.,, & couldn't get them to line up better.
It was pretty bad. :eek:

I would pull the V - cover & check that out. ;)

Added,,

Did you completely remove the governor from inside the case ??

I
That's what I was thinking. It sounds to me like the intake valve may be staying open and causing the cylinder to load too much. With such a small bore and stroke they might not notice it when pulling the engine over. They also bog and are slow to build power when the clutch is worn or not a good match for the motor.
 
#6
I bought a Doodlebug that had Predator 79cc with a governor "removed" and was very unimpressed. I can't imagine how bad it was stock. However, I watched a video of a guy who put one in a Power wheels jeep with a small metal frame and it did surprisingly well. He did intake and exhaust work too. If done correctly they are capable of about 7hp but I believe that includes a little head work.
 
#9
sorry forgot about this post. i did run it for a few mins before i removed the gov all the way. i will check valves. anyone know the valve lash for these 79cc
 
#11
While your there check the torque on the head bolts, they can have a compression issue from that too. If you removed the governor did you take out the detent? The paddle inside can be a little piece of work as well.
 
#12
I'd suggest 17 ft lbs since that is basically what is on all the clone motors for head bolt torque. I spent about 20 mins searching for answers for you. Post a question on the YouTube video I linked with the Power Wheels jeep, that guy built his engine himself.
 
#13
so i opened the valve cover and found the push rods and rockers not even onto eachother correctly. i cant find my feeler gauge put so will have to wait until i buy a new set
 

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