HS40 carb air leak

Old_iron

Old_iron

#1
#1
I spent some today trying to get my HS40 up and running. I could it to run at pull choke but nothing I did get get it torun past full choke. After doing some reading I sprayed carb cleaner around different parts of the carb while the engine was running. Lo and behold, the throttle shaft seems like its leaking air.

  1. Is there anying worth doing to fix this?
  2. Are the chinese carbs on ebay any good, and other than the adjustment on the bottom is there anything else to look out for?
  3. Are the carbs for the H30 and HS40 different?


Thanks
 
bikebudy

bikebudy

Banned - Must pay $500
#2
#2
1. you could see if replacing the throttle shaft would fix the leak.
If you shaft is badly worn? this should help fix it. If the carb body is worn, you may need a carb.

2. You will hear two stories here, I have never had a problem with Chinese carbs off e-bay and I have now used 7 of them.
Others say they have had problems?

If your carb has the High end adjustment screw on the bottom of the float bole, it most likely has the low end screw on the
left side near the carb flange. I always start at 1 1/4 turn out on the two screws and once running set up from there.

3. H30 & H40 are pretty much the same carb but, could be set up completely different as well.
 
markus

markus

Well-Known Member
#3
#3
Did you have the current carb apart and correctly go thru and rebuild it or at least a really good cleaning of the jets and air passages? Its gotta be a REALLY BAD leak at the throttle shaft to make that be the actual cause, they are not an airtight fit to begin with.

Just like any cheap china made thing, you take your chances as to if its going to be usable out of the box. biggest problem I have had with them has to do with folded over gaskets and floats with holes in them. So If I have to use one, anymore I just order a brass float and seal kit to try an avoid any hassles and just "rebuild" it right out of the box. I have seen people complain of idle issues, I have not really seen that myself with them, but I rarely use them. I do what I can with original carb bodies when possible.

The most workable version for the small frame engines will be like this one in this ebay listing, Has that long choke lever so it can be twisted to fit many apps, has high and low needle settings, and a 90 degree fuel inlet. This was just a random listing, with good photos of the stuff you need to watch for to make it work correctly and fit the best for recreational engine apps, I know nothing about the seller or anything like that)

Carburetor for Tecumseh 631921 632284 631070A Fits Many H25 H30 H35 Engines US | eBay
 
Last edited:
Old_iron

Old_iron

#4
#4
I did clean the carb out really well. I tried the standard default screw adjustments plus a myriad of other combinations. I am thinking the carb body is worn since aluminum is softer than whatever the shaft is made frame.
I will try the ebay carb route and see how that goes.
 
markus

markus

Well-Known Member
#5
#5
Old_iron said:
I did clean the carb out really well. I tried the standard default screw adjustments plus a myriad of other combinations. I am thinking the carb body is worn since aluminum is softer than whatever the shaft is made frame.
I will try the ebay carb route and see how that goes.
Click to expand...
Its actually the other way around, the shaft will wear before the body does. Best of luck :thumbsup:
 
You must log in or register to reply here.
Top