The 1872 starts very hard, why?

1811woody · #1 01-04-2014, 09:15 PM

When first trying to start the cub after it sat for about a week I cranked and cranked and cranked... occasionally it would try to start and then kick the starter out with out starting. I checked the fuel filter it was full of fuel I lightly pressurized the tank to get fuel to the carb still no start. As a last resort I gave it a shot of ether still didn't start until I gave it a few more shots then it finally hit but acted as though it was really starved for gas (barely running) but finally took off and ran good. I let it run for a few minutes turned it off and checked the spark plugs one was gapped at .035 the other at .025 I gapped them both at .025 like kohler specs said. They were a little carboned up but over all looked to be in good shape with no signs of oil fouling, to lean etc.The electrode was like new. I then grounded them to the block and turned the engine over they have a nice blue spark. You would think if it were a fuel problem then it would have started when I first sprayed it with ether and if it were a spark problem then I wouldn't have the good blue spark. When its running it purrs like a kitten and when I give it the throttle it roars like a lion. What am I missing, what are some of the issues that the magnums had as far a starting problems.

ken6x6 · #2 01-04-2014, 10:08 PM

looks like your cub caught the 1872 flu that's been going around. i think your the 4th member i've seen in the past 2 weeks with the same issue.

i hope mine doesn't catch it.

1811woody · #3 01-04-2014, 10:28 PM

It wasn't to long ago I was telling that to A Cecil. I think there is something going around it must be getting spread through this forum LOL. Good luck with yours.

ACecil · #4 01-04-2014, 10:40 PM

Something definitely going around with the 1872's. My buddy checked today and my 1872 hardly had any spark. Going to have the ignition module replaced.

1811woody · #5 01-05-2014, 12:49 AM

Did that cause it to be a yellowish spark or was still a good blue spark?

inspectorudy · #6 01-05-2014, 01:25 AM

My experience similar to yours turned out to be crud in the tank, line and carb. Not enough to keep from running but enough to make it real hard to start and make it run hot due to being lean. Buy a new plug but check the fuel and carb too. Get a good clear glass jar and let all of the gas drain into it and let it sit for a day to see if you have any sediment in it. Do it before the filter just to be sure that it is there or not. Then if it is, clean and flush the tank, get a new fuel line/filter and clean the carb and all of it's orifices.
Good luck

ccpullin · #7 01-05-2014, 09:24 AM

I have placed electric fuel pumps on my supers and it has taken care of the same type of starting issues that I had as the carburetor is now full of fuel before attempting to start. Also I always bring the throttle up 1/3, start cranking the engine over and after it gets up to speed (3 seconds) then pull the choke out until it fires, then partially push it back in and they usually take off and start.

When it's cold out everything plays a role. I assume you have good gas (not some from last summer), the battery is strong and winter oil in it. When it is running and the hydro is in neutral (no brake on) does it sit there or want to move? If it moves a little forward or back it needs adjusted or it will drag when starting the engine.

Basically with a centrifugal type starter drive, once the engine fires once and does not continue to fire and start, the initial cylinder fire takes the load off of the starter and the engine will throw the starter drive out. It's a common problem especially in the winter and is why most starters now have a solenoid to hold the drive in. Hope some of this may help!

1811woody · #8 01-05-2014, 11:30 AM

Thanks for the info guys! Its a new day I'll do some more tinkering based on your info and see what I can figure out. I'm still curious if it was a fuel problem shouldn't the starting fluid allow it to at least hit? I did some torqueing of bolts on the intake manifold and carb last night the manifold bolts were a little loose (vacuum leak)? The engine had already been run so of course it fired right up I'll see if it helped at all today after sitting. Its funny the seller said it was really cold blooded he didn't say it was near impossible to start I guess I should of asked for clarification. Of course when I went to go look at it he had already started it so it started right up for me.

ccpullin · #9 01-05-2014, 11:58 AM

Quote:

Originally Posted by 1811woody

Thanks for the info guys! Its a new day I'll do some more tinkering based on your info and see what I can figure out. I'm still curious if it was a fuel problem shouldn't the starting fluid allow it to at least hit? I did some torqueing of bolts on the intake manifold and carb last night the manifold bolts were a little loose (vacuum leak)? The engine had already been run so of course it fired right up I'll see if it helped at all today after sitting. Its funny the seller said it was really cold blooded he didn't say it was near impossible to start I guess I should of asked for clarification. Of course when I went to go look at it he had already started it so it started right up for me.

Yes, it should fire on starting fluid, although it like gasoline has a shelf life. We don't any more, although in the past inflated truck tires and started the old 2 cycle Detroit's with it and found if the can was a year or more old it had went bad. Don't recommend using starting fluid on your Kohler and should not need to. Just need to determine the hard start issue and repair. Even though the fuel level in the tank is higher than the carburetor, it will not free flow fuel through the fuel pump and if the fuel in the carburetor evaporates due to the engine being warm when shut off, an electric fuel pump will refill it before starting. I have a JD 318 and before I installed an electric fuel pump, if it sat for over a week (summer and winter) you had to crank and crank to get started. Now I just turn the key on, wait 5 seconds and start it right up. If you decide to install an electric fuel pump be sure to get a low pressure one (3.5 pounds or less) otherwise the needle/seat in the carburetor will not control the fuel level in it!

1811woody · #10 01-05-2014, 12:27 PM

Quote:

Originally Posted by ccpullin

Yes, it should fire on starting fluid, although it like gasoline has a shelf life. We don't any more, although in the past inflated truck tires and started the old 2 cycle Detroit's with it and found if the can was a year or more old it had went bad. Don't recommend using starting fluid on your Kohler and should not need to. Just need to determine the hard start issue and repair. Even though the fuel level in the tank is higher than the carburetor, it will not free flow fuel through the fuel pump and if the fuel in the carburetor evaporates due to the engine being warm when shut off, an electric fuel pump will refill it before starting. I have a JD 318 and before I installed an electric fuel pump, if it sat for over a week (summer and winter) you had to crank and crank to get started. Now I just turn the key on, wait 5 seconds and start it right up. If you decide to install an electric fuel pump be sure to get a low pressure one (3.5 pounds or less) otherwise the needle/seat in the carburetor will not control the fuel level in it!

I agree about the tank and fuel flow that was proven to me on my 1811 with m18 if fuel was below 1/2 tank it took forever to get the pump to pull fuel to the carb so I'm sure this 1872 has the same issue. Do you by chance know the part number of the pump you use?