Weekend Freedom Machines banner


1015 Views 15 Replies 10 Participants Last post by  sreynolds
Used a friend's new (to them) 425 today. Mowed for 1/2 hour and shut it off. Had a slight run-on. Sat for 1/2 hour. Would not crank. Pulled plugs- cylinders full of fuel. Mowed for 1/2 hour. Shut off fine. Removed fuel cap and tank had pressure in it. Cap says Non Vented on it. My 425 has a vented cap. Did they change this over the model years? I also noticed a previous owner installed a shut off valve in the fuel line so I wondered if had happened before. Anyone have any ideas? Thanks.
1 - 16 of 16 Posts
My 1993 425 is non Vented and as far as I can tell the Shut of if located on the left side under the side cover is original, yesterday I wanted to test my pump and after shutting of the key the fuel flowed all by itself so there must be pressure in the tank .
The newer caps are vented. There have been numerous posts about this problem. Most indicate tank venting is part of the 'flooding hot' problem. If the tank builds pressure, it can cause flooding during a 'hot soak', shut it off, let it sit, engine heat soaks the fuel system and caused fuel to boil over, into the intake manifold. They're hard to start until it evaporates........check the previous 425 posts for more info.
Fred, I have an early model 425 that runs very well with only 550 hours. Should I switch my non-vented gas cap to a new vented cap. Thanks Fred
I was wondering the same thing. Thought I might just drill a small (1/32 or less) hole in it.
I drilled mine with a .048 carb jet drill. The problem is, when parked up on my elevated ramps with the front end up to clean under the mower deck, the fuel will leak and run down the back if the tank is over 3/4 full. Once it's down to half, it doesn't leak.

That's a big problem because it hits the rear deck as well as killing the grass if you clean in the wrong spot. I tried backing the tractor up on the ramps, but it's not as convenient for cleaning under the deck with the back end up, as opposed to raising the front.

Eventually, the solution is a new vented cap, for now I just don't fill the tank before mowing. Yes, drilling the cap will vent the tank and cure the pressure build-up problem.
Hi Everyone.
Well I have been using my 72/ 110 for OUR Halloween train more.Trouble I am have that it is not charging.At WOT it is discharging and at idle it is putting on a small charge? Any Ideas
Ken K
See less See more
You need to do the test procedures as described by the Service Manual. That will tell you if it is the switch, a broken wire, stator or voltage regulator. If not you are just guessing and throwing parts at the tractor. You only need a VOM meter to do the tests but the procedure is a bit long to type here. Roger
I would think the WOT vs. idle charge state is not accurate - my guess is that your regulator is either making DC or it isn't. If you have a VOM you'll be able to determine if your regulator is being fed AC and outputting DC, and that will tell you if the fault is pre regulator, post regulator, or just plain regulator.
To add to the pre regulator, posts regulator or regulator, there is the real possibility of pre-stator aka FLYWHEEL. That is a nightmare in and of itself.

In short ,if there is no ac voltage AFTER you change the stator, it is the flywheel.........ask me how I know.
check your wiring

broken case on the wiring cause a lot of problem

check the connection for loose, rusty or dirty connection

I have been working on a 112 and I check my wiring over and all looked good
one of the connection to the voltage regulator was dirty and loose
clean it and tighten it up - all is good now

good luck - hope it is some thing simple
Thanks Glen
Its so easy to just say "Yea the connections look good"until you really get in there and clean them up.You don't know!
Ken Had This Problem With My 110. Check The Key Switch . Mine HAD A Burnt Terminal. Hook Up Your MeteR OR Load Tester And Watch For A Voltage Spike.
Well its been a year and my friend has determined that the stator is bad.Should I go New or used ?
The new ones are only 50.00 on ebay and that is for the KOHLER brand.

You don't have to bid on it. There are many "stores" selling them on ebay. Click on buy it now option.
1 - 16 of 16 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.