Advice anyone?

Fri Jun 15, 2012 7:46 pm

:help: New to the forum, proud owner of a cub loboy 154 for the past 4 years. Now with a problem looking for help.
My Cub had been running fine for 3 + yrs.,toward end of last mowing season she started losing power and eventually didn't have enough guts to engage mower. Over the winter I put new rings ,valves, springs, cap, rotor, points, condenser, wires, fuel filter, battery. Ran fine for first 4 to 5 times mowing 3.5 acres each time.Developed a problem back-firing out of exhaust and cutting out when running throttle in high also fuel leaking from carb. drain hole when tractor is off. I've since rebuilt carb. and have been pulling my hair out for 2wks.,nothing helped. :? Any advice anyone????? Really like my tractor and don't want to give up.(I've read alot of the forum and think you guys are very helpful to others)

Re: Advice anyone?

Fri Jun 15, 2012 7:57 pm

Thinking ignition related. Double check everything ignition related. Thinking timing slipped - some how. Check with timing light.

Is the carbureton problem, flooding, solved?

Re: Advice anyone?

Fri Jun 15, 2012 8:35 pm

I haven't got the carb. problem fixed yet , I think I may have the float set at the wrong level or the needle and seat are bad new one didn't resemble original ones. I was confused because the carb kit said to set float at 1 13/16 to 1 15/16 from mating surface ,so that's what I set (bent the float to),then I read my IH book and it suggests a height of 1 13/32. At the 1 13/16 to 1 15/16 the tractor would run for about 45 second then run out of gas ,wait for 1 min. start back up , run for45 sec. run out of gas again. I then sat it to book spec 1 13/32 and it now runs gas out the drain hole. So I think I need to tear carb . back apart and find happy med. or do you know proper setting?
Thanks for the Quick reply

Re: Advice anyone?

Fri Jun 15, 2012 9:28 pm

Use the Service Manual, fuel system section. Following is how I bench test my Cub carburetors for fuel level in the bowl. Leaks will also show up during the bench tests. I use a plastic hose on the carburetor inlet, use rubbing alcohol, pour alcohol in the inlet hose and check fluid level in carburetor bowl.

Below is with the carburetor installed on the tractor.
Get a hose barb to fit the carburetor bowl drain hole and about 3 feet of clear plastic tubing to fit the barb. Install the barb and plastic hose. Hold the open end of the hose close to and above the carburetor. Turn on the fuel at the gas tank. Measure from the top of the fuel in the hose to the top of the bowl. Fuel level should be 9/16 to 5/8" below the two carburetor halves.

Re: Advice anyone?

Fri Jun 15, 2012 9:48 pm

Thanks Eugene, I'll try this tomorrow and let you know how I make out. Appreciate all the advice and tricks of trade for the cub loboy .

Re: Advice anyone?

Sat Jun 16, 2012 10:46 am ... index.html

Above link has several discussions and photos on carburetor repair, including testing and setting the float height.

Re: Advice anyone?

Sat Jun 16, 2012 2:51 pm

Check the fuekl bowel for water too. I've seen the tractor run great them go off the deep end stalling and sputtering when some water goes thru it then it runs ok again. Check the distributor cap for water too in it.

On adjusting the float first i would remove the carb and keep the hoes attached(gas). Remove the bowel and hold the float up and turn the gas on to see if the needle and seat are working properly. If its shutting off the gas the way it should i would drop the float a tad and assemble it and try it. I would keep on dropping/lowering the float till it shuts off the gas in the upward position like it should yet turn the gas on when it lowers. Does your float have any gas in it?? "bad float" Does your float, float in a coffee can of gas? If it sinks you need a new float.

I work on so many carbs i find that setting the top of the float parallel to where the bowel surface on the carb body is a good starting place.

Re: Advice anyone?

Sat Jun 16, 2012 6:54 pm

BigBill wrote:I work on so many carbs i find that setting the top of the float parallel to where the bowel surface on the carb body is a good starting place.

Tough to judge that with a round float.

Re: Advice anyone?

Thu Jun 21, 2012 7:12 pm

THANKS TO ALL, got the old girl running again and she's running like a new one!!!! I ended up getting the carb. and float set correctly , then moved on to replacing everything ignition wise. First, new sparkplug wires , that wasn't it ,new rotor, not that neither,new condenser, BINGO!!! She's running like a top , cut grass for 3 1/2 hrs and she never missed a beat.Thanks again everybody for all the advice, really enjoy the site and forum and am glad I joined.