By marty on Unrecorded Date: Edit

i have a max 4 1998 20 hp. excellent shape. took it to my local dealer he charged me 369.00 for a tune up. lucky me. still does not run well. my friend who has max 4 helped it a little by increasing rpm to 3600 but that is not a real fix. engine wants to stall a little when you first give it some gas after it warms up for 5 min it is a letter better but not much. just sluggish. my friend even said it needs to run alot better after a tune up. i did notice my choke knob does not go really in all the way. ( likes asbout 1/8 inch )need some ideas i am out of money. marty mdo3059680@aol.com

By Larry Houghton on Unrecorded Date: Edit

Marty.Check and make sure choke is not partly closed.Also idle mixture screw could be out of adjustment.You didnt say if it was smoking or not.If it is it's to rich,no smoke to lean also did the gas filter get changed could be maybe piece of dirt in carb. or something blocking gas line.

By marty on Unrecorded Date: Edit

larry. thanks for the email. does not smoke but did back fire today when i turned motor off. i know we are running it rich because my friend turned idel screw so at least i could run it. but that is really not a fix. if you could e-mail me your email address so we can talk more about it. thanks. marty mdo3059680@aol.com

By scrambler71 on Unrecorded Date: Edit

to marty
fromdaveyoder
your choke might be suck a litle bit
and look at your carbrator
for dirt in side the carb bowl and make sure
in not the float
and start your max right up
and adjust idle set screw
and check fuel filter for dirt in the filter
and look at the gas line for any leak
crack in the line or holes
and make sure the fuel line tighted up
their you go marty
then it should run very good again

By Larry Houghton on Unrecorded Date: Edit

Marty. Forgot one thing maybe two. First check plugs and check around block of engine for lose wires.Kohler has a smart spark system and maybe a wire got knocked apart.
My e-mail is lhoughton@quicklinks.on.ca

By James Todd on Unrecorded Date: Edit

My 95 Kohler 20 has a real hard time starting once the engine is HOT. Starts fine with choke when cold. I just purchased this machine so have no histoy other than it has very low hours. When running it has a slight hesitation when reving up but seems to run strong. Idles fine. Any help would be great!

By mikesmax on Unrecorded Date: Edit

JIm thats easy your carb is dirty clean all the jets and blow air thru it and it will be fine LATER!

By Barry Smythe on Unrecorded Date: Edit

If all the good suggestions do not help the situation,
consider replacing the fuel pump with a new one. I
found the pump that came with the Kohler engine when
new was quite weak and the engine always took a bit of
cranking before it started. When I replaced the pump
with a new (plastic) one things really changed for the
better. It always starts almost instantly now. What a
difference. That was three or four years ago and it still
starts fast. Backfiring is a sign of too lean usually.
Could it be ice crystals in the fuel jamming up in the
filter or the carburetor ? Try some gas line antifreeze if
you are in a frosty location.

Good luck!

By James Todd on Unrecorded Date: Edit

Great. I'm going to put a timing light on it just to be sure its fuel before I take the carb apart and clean. Thanks so much for your advice.

Jim

By Dave Johnston on Unrecorded Date: Edit

ALl these messages seem to focus on the engine. What about the GAS? If you "fill it up" with eight gallons and then do not run it much, you end up running "old" gas thru the fuel filter, carb and valves. Old gas is gummy gas. Drain out all the gas, fill with a gallon or two of new gas and dump in some gas line cleaner. If you MUST fill it up it up, put some fuel stablizer in it. That may help a lot.