Hs50 stalls...

#1
Hs50
Bought as a project/ history unknown
Aftermarket carb
New air filter
New head gasket/has a leak though
Remote gas tank

It runs well, seems to have plenty of power and for the most part idles fine. The problems happen as I come to a stop, worse if I come to a hard stop. If it doesn’t stall right away it’ll idle very low and if I chirp the throttle to pick it up it’ll stall. If I tickle the throttle a few times it generally won’t stall. When it does stall it starts up just fine.

The head gasket leak- at some point in its life someone crapped up the threads in the block on one of the head bolts and in fixing it they redrilled/tapped the block out of alignment to the head so I worried to hole in the head to get it realigned. I haven’t pulled the tin to confirm that that’s where the leak is but it’s too close to the bad bolt to be coincidence. I haven’t a clue if this has anything to do with the stalling but...

Thanks
 
#3
I agree, (I should’ve mentioned that I put On new intake gaskets) I had this problem on another engine and wasn’t ever able to fix it. I did a few searches and wasn’t able to find anything. Maybe I used the wrong word(s)...

I pulled the head and “flattened” both the block and head. This is just a guess but it looks like the original bolt broke, they tried to flush it to the deck, drilled and retapped. They left part of the old bolt proud of the deck. I didn’t think it was enough to cause problems but I’ve got it flush now.

I also noticed that the intake valve doesn’t fully close at TDC so I pulled the breather and I’ve got 0.006” on the intake and 0.008” on the exhaust. I pulled the intake valve and will lap it tomorrow. Again, I don’t know if any of this will help the with it stalling but I’m 41yrs old and haven’t ever lapped a valve which just don’t seem right.
 
#4
The leak at the head is fixed, the valves have been lapped and both have 0.005” of lash. It has noticeably more power but still stalls when coming to a stop. When it doesn’t stall right away it idles super slow and a quick roll of the throttle kills it but if I roll it a few times the idles comes back up. Wish I had another good carb to try...
 
#5
Does it have a fuel filter? Timed correctly? Carb cleaned and rebuilt? Fuel line collapsing? Gas tank height? I’d lean towards the carb...at this point you may just want to tear it apart and redo all your issues at once...clean valves up...rebuild carb...time...fix your head issue correctly....that way you can enjoy it
 
#6
Head and valves are good. The carb is a new knock off. I just adjusted the float using an 11/64” bit and it’s better as in it doesn’t stall as often. It’s running well enough that it doesn’t bother me but I’ll pull the carb once more to double check the float level. The bottom of the fuel tank is a good 5” above the engine and the fuel line and filter are new so I’m pretty sure it’s just something funk with the carb. I have an old Tecumseh carb that I cleaned and rebuilt that I can try.
 
#7
Tried another carb, same thing if not worse. I’m putting the first carb back on and calling a day. I still hope to fix it but for today it’s good enough.
 
#8
Have you gone thru the tec L head service manual and looked at the governor set-up? Most engines I get like yours, the previous owner has changed the governor in an effort to cure an ill. The lever/stem can be out of position, the linkage bent, and the spring might need replacing.
 
#9
Ha, another thing I should’ve mentioned! No governor. I have been using the service manual. I keep it open on my phone.

Head gasket leak fixed
Valves lapped and lash set to 0.005”/0.005”
No governor
Carbs- 1 new knock off 1 cleaned and rebuilt
Tecumseh, same results
New gaskets
New fuel line, filter and tank
 
#10
Interestingly, I just put a remote gas tank on another bike in pretty much the exact same setup and now this bike is having trouble idling. The tank is a cylinder mount parallel to the fame in front of the seat, petcock/filter mounted to the tank, single piece of 1/2” fuel line running to the Carb. 04621562-A99D-44EB-9F2A-D64ABAADB45B.jpeg
 
#12
I believe so. I feel like it could be a little more open but with that in mind while the bike was doing its low idle thing I removed the cap and didn’t notice any change.
 
#14
7/8 of a turn. The bike was running great before I swapped the tank. The only other thing I changed was it now has some of that ethanol free can gas in it, had been using pump gas. I’ve got the same gas in other bikes that aren’t stalling.
 
#15
Is
7/8 of a turn. The bike was running great before I swapped the tank. The only other thing I changed was it now has some of that ethanol free can gas in it, had been using pump gas. I’ve got the same gas in other bikes that aren’t stalling.
Is there a filter integral to the tank fuel barbed fitting like a Honda?
 
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