Sachs Hercules engine problems

gener hernandez /

Greetings,just joined the group,can anybody please help on what to do,i'm new on mopeds,can anybody please advise what to do,i have just finished rebuilding a sachs hercules which i brought from canada,its got new rings,new clone china carb,and runs well, issue is its leaking gas on the decompression exhaust port,and has knocking sounds,lately its leaking what seems to be ATF,because its reddish in color,will be very grateful for any assistance and recommendations,thanks,

gener from the philippines

Re: Sachs Hercules engine problems

What do you mean when you say it's leaking gas on the decompression exhaust port? Knocking noise from where? Video? What area is the transmission fluid coming from? Pics and videos are always a big help.

Re: Sachs Hercules engine problems

yea wow that's a lot of different problems you incompletely describe...

leaking from the decomp I suspect you mean the little hole on the underside of the cylinder next to the exhaust. This leaks if your decomp valve leaks, and is a common problem. solution explained here:

Knocking could be anything, be more specific as to where. could be the

if it's leaking gas from the tank, it's probably the petcock seals. easily replaced, just get a new petcock from doscycles or treats, or diassemble the one you got and tryn reassemble with new seals (replace in kind is best and easiest)

if it's leaking gas from the carb, chances are it's the float bowl s4eal. it's very common for those to pop out and leak on the clones. You can find replacement gaskets fr the float bowl, or just shut off the gas when not riding

Transmission fluid can leak from a few places but 3 are most likely. 1 is the clutch cover. if you took the 5 bolt cover off the clutch ever, and didn't replace the gasket with a new one, it's leaking there.

If you had to reall torque on the drain plug screw to fill the transmission and wrecked the threads or punched a small hole through, it will leak.

the third one's the pedal shaft seal. they wear, especially if you have or had a loose chain it can snag that and wreck the output seal on the pedal shaft. measure seal size and replace it with a new one. you can do this just pulling the old seal out once the crank pedal arm is off, and pushing a new one in.


Re: Sachs Hercules engine problems

gener hernandez /

ok sir stephen,thanks for reply,if i have a leaking decomp,can i just pull it out and clean it,i just don"t want to plug the decomp hole,to maintain originality,(when i first rode it for a test drive,people were really awed and curious when they saw it running!,my neighbor even offered to buy it!)also can it be possible that the faulty decomp causes the knocking sound,i'm positive its coming from the jug as well as the atf leak ,will try to take pics and videos, cheers, gener

Re: Sachs Hercules engine problems

If you want to try to repair it, you'll need to try to restore the spring action that holds it closed, and you'll want to lap it with valve lapping compound. Lots of valve lapping videos online, not for this woped specifically but enough to give you an idea of what you need. pull it out with I think it's just a 15mm wrench and you can look at it and work on it.

Plugging it doesn't really remove the originality, you could do it just to test if it makes an improvement and keep the original valve around to swap back on whenever. I think you can buy replacement valves if you email they might have some (probably not listed online but they have lots of back stock stuff that's not listed on their site) and there's also mopedjunkyard. Usually and doscycles are best sources for parts, but treats I don't think has much stock replacements. 1977mopeds is best to avoid anymore, their service has failed. mopedjunkyard is typically pricier but often has more original parts.

Re: Sachs Hercules engine problems

gener hernandez /

hi sir willd, thanks again for reply,yes i'm familiar with valve lapping,we call it here "asinta barbula!(aiming the valve) have done it before on small hondas,can't believe i'll be lapping a valve on a 2 stroke! cheers


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