Alright so I got the new carb & installed it. Turns out I'm STILL not getting fuel! Looks like the float in the carbs fuel bowl won't go back down. Is this a desighn flaw with carbs? I'm using regular unleted gas fresh from the pump so gas shouldn't be the problem.
Help! 4 stroke bike not getting fuel.
- Thread starter bikejock
- Start date
Just out of curiosity, has anyone ever adapted a 2 stroke carb to a 4 stroke?
Back when I had my 2 stroke bike I never had any problems with the carb on that bike. But on my 4 stroke the only problem I'm struggling with the most is the carb on my HS 142F.
Also a fuel injection system would be awesome for these 4 stroke motors & proabably give some extra performance.
It's a modern 4 stroke so you'd think fuel injection would be standard on 4 strokes of any size these days. Carb fuel systems seems pretty primitive.
Back when I had my 2 stroke bike I never had any problems with the carb on that bike. But on my 4 stroke the only problem I'm struggling with the most is the carb on my HS 142F.
Also a fuel injection system would be awesome for these 4 stroke motors & proabably give some extra performance.
It's a modern 4 stroke so you'd think fuel injection would be standard on 4 strokes of any size these days. Carb fuel systems seems pretty primitive.
Slogger
Member
I'd say go back to square one here. Put your palm over the carb throat, seal it off, open the throttle and pull the rope.
Your hand should get sucked on by the vacuum.
If it doesn't, you either have a stuck closed intake valve or broken off cam lobe in there or something.
If it does, you have a clogged inlet fitting, float needle seat or main jet if it isn't getting any gas at all.
So, does it suck air?
Your hand should get sucked on by the vacuum.
If it doesn't, you either have a stuck closed intake valve or broken off cam lobe in there or something.
If it does, you have a clogged inlet fitting, float needle seat or main jet if it isn't getting any gas at all.
So, does it suck air?
Slogger
Member
I just saw your last post, about fuel injection.
EFI requires high fuel pressure, a lot of electrical power and precise senders for the crank position that tells the computer when to inject fuel and how much. Throttle position sensor, mass flow sensor, on and on. About 10 amps of 12 volt power required.
It's just not feasible on a $200, wee little engine.
I have read of others using NT carbs on HF engines. They say they worked fine.
Hope this helps some.
EFI requires high fuel pressure, a lot of electrical power and precise senders for the crank position that tells the computer when to inject fuel and how much. Throttle position sensor, mass flow sensor, on and on. About 10 amps of 12 volt power required.
It's just not feasible on a $200, wee little engine.
I have read of others using NT carbs on HF engines. They say they worked fine.
Hope this helps some.
The_Aleman
Well-Known Member
Are you sure your gas tank cap is venting properly? Try starting/running the engine without the gas cap.
Sometimes those vented caps don't work very well.
Sometimes those vented caps don't work very well.
KCvale
In memory of KCvale 1959 - 2019
Yes.
The HS intake holes are the same as a 2-stroke intake so you can use a 2-stroke intake.
An offset worked best, we just did some creative cutting.
Get a catch can for the breather hose, it hampers performance if put in the air cleaner like that last one.
Ok after installing the new carb I still was getting fuel line blockage for what ever reason from half way from my fuel line to the tank. But I was able to use the fuel that was in the line & fuel bowl to get it to start again. But the problem is it won't start unless I have the throttle open which could be bad for the engine always having to start it that way.
People say that having to start an engine with the throttle open is often a sign of flooding but I don't think that's the case here. If it were flooding, I would see gas leaking out of the carbs clear exaust tube.
The problem that might be causing this could be the float bowl keeps filling to high causing the float to be in the up position all the time, a clogged jet (don't see that being the case since it's a brand new carb), float level set incorectily (these carbs have no way to adjust the float level which IS a huge design flaw if that's the problem), using ethonol fuel (doubt that's the problem because I'm using regular unleted gas straght from the pumps so it should be ethonol free fuel)
People say that having to start an engine with the throttle open is often a sign of flooding but I don't think that's the case here. If it were flooding, I would see gas leaking out of the carbs clear exaust tube.
The problem that might be causing this could be the float bowl keeps filling to high causing the float to be in the up position all the time, a clogged jet (don't see that being the case since it's a brand new carb), float level set incorectily (these carbs have no way to adjust the float level which IS a huge design flaw if that's the problem), using ethonol fuel (doubt that's the problem because I'm using regular unleted gas straght from the pumps so it should be ethonol free fuel)
crassius
Well-Known Member
- Local time
- 4:13 PM
- Joined
- Jul 23, 2012
- Messages
- 4,550
I'm not sure that you are understanding the float - it is supposed to go as high as it needs to shut off the fuel, then drop a bit as fuel level goes down from use to let in more fuel. If you're not using fuel, it will not go down.
I understand what a float is for problem is I don't think it's working right. Problem is I have no way to figure out why.
The problem is the float won't go down even when I'm trying to use fuel. My fuel valve is in the on position & I got about $1 worth of gas in the tank for testing.
The fuel flows for about a few seconds then an air pocket developes between the middle of the fuel line where my filter is & the gas tank. I know it's not the fuel filter causing the problem because I unplugged my fuel line from my carburetor to drain the gas & it flowed out through the line just fine even with the filter installed. That's why it has me thinking my float is up without ever coming back down after the fuel bowl fills up with gas.
