425 Quit in 7 Degree Weather

[lyle425]

Yes - I am getting spark out of plugs -

 

[john_bud]

Iced carburetor.

Probably have some fuel passages blocked with ice. Heat the tractor up. A space heater aimed at the carb and a blanket over the tractor -- with care that things don't get too hot or touch the heater!!

2-3 hours at 45-60F will probably melt the ice and the stuff you added will work.

jb

 

[lyle425]

Thanks for responding - Do you think this is the case even though I dis-assembled carb and cleaned? - I seemed to be able to blow through jets - although I couldn't actually check all of them

 

[keeney]

In my experience, 90% of all small gas engine problems are carb/fuel related, and almost never the spark, timing, or valves. If the battery is cranking it over, there is almost certainly enough voltage for the ignition to make good spark.

I would suspect bad gas or water in the gas and/or icing in the fuel line. It will take quite a while (like until spring) for an iced carb or fuel line to thaw in a 28 degree garage! Try cranking the heat up in the garage well above freezing for several hours.

Does the gas coming out of the carb smell like gas? If you suspect its bad, drain it all, including disconnecting the fuel line to the carb and draining the float bowl and replace it all with known good fresh gas. A good way to check that the float valve is working and good fuel is flowing through the whole system all in one shot is if the float bowl has a drain on its bottom - you can just drain the whole system from there.

It could also be some contaminant plugged the oriface, jets, or float valve in the carb, but you said you checked all that.

Also, check for any linkage or springs that may have come loose from the carb. Verify that the throttle and chaoke are in reasonable positions while you are trying to start the engine.

- Rick

 

[lyle425]

Wow -- I appreciate your confidence Rick! Just about everyone I talk to is leaning towards this answer - (too bad I can't get my tractor through my front door to warm it up - Somehow I don't think my wife would appreciate it in the living room.)

I connected the float (top half) part of the carb to the gas line and gas flows right through it so no problem on that end of the carb - could I still have a problem elsewhere in the carb ?

 

[keeney]

It only takes a very small piece of ice or some other contaminant to plug the oriface that feeds the jets. The diameterof the hole is measured in thousadths of an inch. Typically on the order of like 0.015 of an inch or so if I remember right.

If you cannot warm the whole machine, you should be able sneak just the carb into the house without your wife finding out.

- Rick

 

[keeney]

I did have an old snowblower once that had a bad cowling on it that let enough snow find its way in to plug the carb air intake completely, but that was a strange case.

 

[lyle425]

I suppose I could just take carb off and bring it (not tractor) into the house - that ought to thaw out any ice in the jets, yes?

 

[Treemonkey1000]

Or borrow her hair drier. Just make sure there isn't any raw gas left around the carb and fuel lines. Or a frozen carb will be the last of your worries.

 

[lyle425]

Ahh - Yes, Rick, I think we were having the same thought at the same time there. Also, I noticed that when I took carb apart earlier this eve I broke gasket -- so that will need to be fixed -- gas is now leaking out of bottom of carb -- Aargh!