rat mower

[r97]

this may help sounds like a similar problem didn't read the whole answer though, to lazy lol, if that doesn't help i will do a more in-depth search

 

[jareeB]

Yes and yes, read post #34.

yeah sorry about that lol.

 

[motor_head]

the idle speed screw isn't set to high is it, might have been beings it was only running on 1 cylinder

 

[newrider3]

The throttle butterfly is as closed as it will go, the idle screw isn't touching. It's not like it's idling a little high, I mean if I open the choke more than a 1/8", it redlines, and keeps climbing until I kill it.

 

[Kaptain Krunch]

Air leak?

 

[newrider3]

I took off the intake and inspected everything, no cracks, gaskets were excellent, bolts were tight. I still have a runaway idle condition. Tried running it with the gov disconnected, and a simple return spring, no change. I started it up and held it at idle (choking it by hand) and sprayed carb cleaner anywhere a vacuum leak would be likely, still no change.

..........

 

[Kaptain Krunch]

I'm not gonna lie, i was too lazy to read the whole thing.

 

[r97]

shot in the dark here, but maybe your carb is putting out too much gas, and it is just running rich until you choke it and its too rich to run, so it slows down until it pulls less and less fuel so it just becomes even with the amount of air and runs normal, hope that makes sens, like i said, shot in the dark, remember, carburetors are tricky things, there is a reason why they don't put them in cars now.

 

[sideways]

remember, carburetors are tricky things, there is a reason why they don't put them in cars now.

And that reason is because it's too hard to make them meet emissions laws, and EFI just generally works better. A well set up Webber will work just as good as EFI at high revs but that's about as good as carbies get. And then there's the starting issues.

Thanks

Hayden

 

[r97]

the thing is just getting them to work perfectly all the time

 

[motor_head]

maybe the butter fly in the carb is bent? otherwise i'd say vacuum leak
can't think of anything else

 

[newrider3]

So, this thing has been taking up space in my garage for a while now, I decided to start messing with it again this weekend.
The stock carb still doesn't work right, so I took it off and threw it as far as I could. Then I dug out some spare Tecumseh carbs (sigh) and intake manifolds.

Took the manifolds, and cut them down to what you see here. Afterwards I used a flap wheel to smooth out the reinforcing ribs to leave a smooth tube.

The two steel flanges also in the pic were actually the original flanges for the muffler. I cut the tube off the right side of them, and they bolted right on to the intake ports.
Add a piece of heater hose each, some hose clamps, and some wire for a throttle linkage, then brace using old push mower throttle parts...

Runs like a champ. Seems like plenty of carb for this engine.

 

[B man]

nice idea.

 

[mudduck7.3]

very nice . i had the same problem with the 18 hp o/c briggs in my build , cleaned the carb and put new hose on the vacum fixed my problem.