engine problems

[newargoowner]

Im having problems with my M18 (18hp kohler). I got 6 hrs on it since its been rebuilt. It was running until yesterday. It started up fine, then i ran it for 20 minutes, so it was warmed up. i shut it down to put on its snow tracks then fired it up and ran it slow in the driveway (back and forth at an idle) to checkout the tracks. then it just stalled. i tried to start it but all it did was crank over. I pulled the chock and it would start up then stall. then it wouldn't start at all. i poured some gas down into the carb it would run for a few seconds. so i did that enough to get the machine in the garage for the night. i figured the fuel pump went since during the rebuild i had the carb cleaned and rebuilt, replaced the fuel filter, and had new gas with stablizer. then this morning i went to start the machine and carb was filling up with gas (flooding). i check the sparck plugs. the front plug was soaking wet with gas but the back one was bone dry? so now the its getting to much gas. I'm assuming there is something wrong with the fuel pump, i order one through NAPA but it won't be in until tuesday. has anyone seen this before?

[Bazooo guy]

Sounds like the float or needle valve is leaking.
Pull the float bowl and check for debris.....make sure the float is adjusted properly and the needle and seat are clear.
Also check the crankcase oil for gas and change the oil if its contaminated.

[newargoowner]

I checked the oil level it is about 1/8 above the full mark, i figured i would have to change the oil since it was dumping alot of fuel into the carb. I needed to change the oil for winter (10w30) anyway. I'm going to take the carb off and check for debris in the bowl. i'm still going to replace the fuel pump since it didn't run for a year and half before the rebuild and i read that the nylon will dryout if not kept wet and malifunction. will update when i find out something.

[Bazooo guy]

You could check the flow of your pump before you replace it.

[newargoowner]

I pulled the carb off yesterday and found some sediment in the bottom of the float bowl. I also see some floating in the see threw fuel filter i put on last year. I did test the pump during the rebuild and redid it yesterday and it seems to be pumping out alot more fuel than before. I don't know if this if possible? but i'm going to replace it anyway to rule it out. i'm going to replace the fuel filter too. i carb cleaned the float bowl area and will take out the main/idle needles and spay down into the holes. I hope i don't have to rebuild the carb again. The float seemed to be working fine(not stuck) I don't know if that little bit of sediment in the bottom of the bowl would cause the float to stick?

[Bazooo guy]

Any sediment in the carb will cause problems.
I would drain the gas tank and make sure its clean inside.
Is your tank steel? Rust can form inside when its dry and flake off when you put fresh gas in it.
Check that the float is not cracked and filling with fuel and the needle/seat adjustment is correct.

[amphibious drew]

Did you replace your fuel lines before the new engine was installed? Old lines will decompose from the inside and cause all sorts of fuel delivery issues.

[newargoowner]

The tank is poly. i did clean it out (i thought pretty good) I can't take the tankout of the machine with out splitting the tub (i not doing that) I'm going to try to such out the tank again. Yes i did replace the fuel lines during the rebuild. The float is new (replaced when the carb was rebuilt) the motor was idling and running good before this happened.

[teeko]

All very good advice but I would also check the needle itself. If there is a visible ring around the needle where it mates with the seat, there could be leakage. A new needle and seat is very reasonable, usually 5 or 10 bucks. Ethanol could be another issue. Where do you buy your fuel and what grade do you buy? Remember your car has many cylinders and a computer to tell it what to do. Small engines may not be compatible with the rates of ethanol found in some lower grades of gasoline. For the amount of fuel you go through in your machine, I recommend running premium grade from a reputable company such as shell V-power. I ran cheap gas in an old snowmobile and within 5 minutes of running, it quit. I rebuilt the carb and it ran like crap. I realized that ALL my rubber intake gaskets had the consistency of 'goo'. Replaced them and then it ran fine. It was the ethanol that dissolved the rubber.

[newargoowner]

I buy BP 87 octane and and add stabilizer to it. I just got the fuel tank pulled out of the argo (what a pain in the a$$). I do see some sediment in the bottom (shouldn't the filter stopped it for getting to the carb?). i got to goto work. going to clean it out tomarrow. any suggestion on what to use? dump out what left of the gas and maybe spray it out with a garden hose and then let it dry over night?

[teeko]

Thats how I cleaned mine out. The filters should help keep sediment out. If your oil was overfilled and smelled of gas then I would assume it is a needle and seat problem. If your needle doesn't stop the flow of gas into the bowl it runs into the cylinders and past the rings into the case, increasing the volume of the crankcase, which is why it reads high on the dipstick.

[newargoowner]

I'm going to checkout the float needle. at first the engine wasn't getting gas, then the next day it was flooding... i'm assuming the sediment chocked off the gas then when getting the machine in the garage the sediment caused the needle to stay open. I already drained the oil and will be refilling it with 10w30 for the winter (also changing the oil filter). thanks for the help!

[newargoowner]

Well, she's running good again. I ended up cleaning the tank, new fuel filter and all new fuel line(the other one was alittle short), replaced the fuel pump and cleaned out the carb. I tore apart the old pump and it had alot of corrosion and sediment in it. Thanks for all the help!