Tecumseh carb question

[crosstalk]

The choke is fully open. I pulled the head and found tons of carbon on the intake and exhaust valves, but very little on top of the piston. Also a big pile of carbon inside the exhaust port. Zero valve clearance. Also snapped off flush a muffler support bracket bolt on top of the head. I guess I have some work to do.

[FortyCaliber]

The choke is fully open. I pulled the head and found tons of carbon on the intake and exhaust valves, but very little on top of the piston. Also a big pile of carbon inside the exhaust port. Zero valve clearance. Also snapped off flush a muffler support bracket bolt on top of the head. I guess I have some work to do.

I just finished doing my valves on my 5.5HP Tecumseh. It wouldn't even run at all anymore. Started first pull today, although I still have carb adjustments to make. I guess it's a common problem on Tecumseh from everything I've read.

[thomd51]

surging is because low speed circut in carb body is still plugged. remove idle mix screw ( on side of carb ) shoot carb cleaner in there it should come out ldle holes in carb throat but also from the bottom of carb where main jet adj. threads in. hold carb upside down and look in hole that you took low speed adj. screw out of tap carb , a small rod will fall down and block the hole that the tip of the low speed screw goes into. if you turn the the carb upright it will move out of the way, this rod and passage must be clean TOM.

[bgsengine]

hold carb upside down and look in hole that you took low speed adj. screw out of tap carb , a small rod will fall down and block the hole that the tip of the low speed screw goes into. if you turn the the carb upright it will move out of the way, this rod and passage must be clean TOM.

THAT depends on the carburetor being worked on - not all of them have the metering rod - On some carburetors, you turn the mix screw IN to enrich the mixture (Air adjustment) and those are equipped with these rods you speak of - On others, you turn the screw OUT to enrich the mixture (fuel adjustment) and those are NOT equipped with metering rods.
Easy to spot which is which by looking at the mixture screws - If the original screw has a long untapered smooth shaft before the end comes to a somewhat blunt taper point (after the threaded section) it's an air adjust and should have that rod - if the screw is not installed with the carb held upside down that rod falls in and blocks the tip of the screw when trying to install it, if you try to seat the screw you can mash the screw tip and bend the rod, ruining the carburetor... So those screws must be installed with the carb oriented so bowl is facing down. - If the rod *should* be there, the carb will rattle when shaken (float removed) - if not, then the metering rod may be stuck (gum/varnish) or bent/damaged (prior service attempts)

The "no rattle, its bad" mis-information is an extremely frustrating thing I deal with when customers walk in with a carb and want to buy a new one after reading such information, without the specific disclaimer that NOT ALL OF THESE CARBURETORS have the metering rod - Several of those carbs, I took over the counter, ran through ultrasonic cleaner, reassembled and set base adjustments, customer took it home and their engine started right up and ran fine with no adjustment needed.. Saved them from wasting $80+ on a replacement carburetor they did not need.

The carb in question to this post , if it is original to the engine, is a 632334A carburetor using kit # 632347 , which uses the aforementioned FUEL MIXTURE adjust screw, and this carburetor will NOT have a metering rod.

[38racing]

surging is because low speed circut in carb body is still plugged. remove idle mix screw ( on side of carb ) shoot carb cleaner in there it should come out ldle holes in carb throat but also from the bottom of carb where main jet adj. threads in. hold carb upside down and look in hole that you took low speed adj. screw out of tap carb , a small rod will fall down and block the hole that the tip of the low speed screw goes into. if you turn the the carb upright it will move out of the way, this rod and passage must be clean TOM.

I don't think surging is the issue at this point, I think it's a running too rich problem.

[okie]

Maybe this video will help with the basics of gasoline (from 1935) or not.

Travis

(I can't let a whole day go by without someone posting)


http://www.tvraaca.org/gasoline1935i.htm

[Mek-a-nik]

Maybe this video will help with the basics of gasoline (from 1935) or not.
Travis
(I can't let a whole day go by without someone posting)
http://www.tvraaca.org/gasoline1935i.htm

Should've won an Oscar!
I wonder what the new, ethanol soaked gas drop would look like in cartoon form? Probably some evil, nasty looking thing.
Maybe they did a Buck Rodgers version of the gas drops trip through EFI?

[crosstalk]

Just want to close the thread on this one. After grinding the valves to adjust the lash and cleaning up the carbon, I put the engine back together and it was doing a similar thing (hunting/running rich). I took the carb apart again and removed the welch plugs this time. The idle circuit was clogged. I was able to clear it with more cleaning. The engine is starting and running much better now, though I still have some fine tuning to do on the carb and top speed adjustment. Not sure if I wasted my time with valve adjustment--it probably needed that too, but the carb was the primary problem. Fixed just in time for major snowblowing!