Cub 1811 Kohler M18

[Charlie175]

I need to replace the intake valve on my M18S. CC said the part is NLA and I have looked online and can't find them either.
I can find the M20 intake valves, even though they have a different Part #, I was wondering if they are compatible?
Otherwise is there a hidden source of these valves out there? I see some aftermarket ones, but they just note M18/M20 intake valve which makes me leery.

[J-Mech]

Hello Charlie and welcome to ECC!

I am thinking the M18 and M20 valves are the same. Give me a few minutes and I'll go look.

Might I ask what happened to the valve that it needs replaced?

Show us some pictures of that 1811 too! I've owned one for about 17 years now. One of, if not THE best Cub Cadet GT ever made!

[Charlie175]

Thank you.
I purchased it used in 2000, had 190 hours on it. I think it is a 1989 model. I now have 620 hours on it. Has a 50c deck.
When I got it out from it's long winter nap, when I cranked it, it barely cranked over, fired and then stopped.
Found the case full of gas as the fuel pump stuck open. The right rod broke which busted the lower edge on the jug. When I took it apart I was surprised to see that it had been apart before as the other side rod had broke and you could see where it had bunged up that side. So maybe it has more hours on it that the clock says...
I found a good used jug and took it to a local repair place to have the valves swapped over as I don't have a tool for the valve springs. The repair guy said the intake was burnt bad and needed to be replaced. He showed it to me, it is black and not silver. Not sure what I am looking at but he has been doing repair for 35 years
https://i.vgy.me/Q6LG4G.jpg

[Charlie175]

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[Charlie175]

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[J-Mech]

Very good looking 1811!!
It looks like maybe a 620 hour tractor. Rods can break for a lot of reasons, as you have found out. My 1811 just rolled 2100 hours and it on engine #2, installed at like 1175 hours just before I bought it. I've put just almost 1000 hours on it.

On the valve, while the M18/M20 valves carry different part numbers, I think they are the same and why the Stens replacements list them as one part. The engine specs state the stem size is the same, as is the lift, and blah, blah.... the specs match. Kohler liked to change part numbers for every little thing. If Stens says it fits, it will work. That said, All States Ag Parts (also a company I use a lot) has listed the Kohler valve. May give them a call, or just order it online. As far as are the two valves the same.... I'm about 99.9% sure they will interchange. I do quite a bit of Kohler engine work, and know for sure that there was a valve seat angle change in the Mag series from 45 to 30 deg. The KT and M valves will interchange, and the both the KT17/KT19 and M18/M20 engines are basically the same in build, only that the larger one had a longer stroke. Pretty sure they even used the same jugs, as the compression ratio on the larger engine was higher. I think they just put a longer stroke crank in and left the rest the same.

On another note, I want to encourage you to always check the oil in the engine before you start it for the day. Most people never give it a thought, but small engines can and will have issues from time to time just like this. A simple popping of the hood and pulling a dipstick would have saved you quite a bit of time and money. On the farm, oil always gets checked on every piece of equipment before it starts it's daily chores. Just a good habit to get into. The fuel pump didn't stick open either. It just wore out. Make sure you replace it, along with removing, cleaning and putting a kit in the cab. If you don't already have one, I suggest a fuel filter in line between the tank and the pump. Now is also a good time to replace all the fuel line and drain and flush out your tank.

Good luck and I hope I helped you out! Let us know if you have any more questions!

[Charlie175]

Thanks for the tip on All states. I order tractor parts from there, didn't think about mower parts

[J-Mech]

I didn't think of them either, but it came up when I searched the part number. Otherwise I would have never checked with them either.

[zippy1]

Good looking 1811 Charlie.
I'm going through one right now myself. EVERYONE I've picked up in the past, used, was "used", but not used up. I'm keeping this one, cause I "need" another tractor.
Welcome to the group, pretty good bunch here, and a great deal of knowledge throughout. You got one of the better guys to answer your question. He's (Jon) is a walking, talking book of knowledge.

[Charlie175]

Thanks!
Been eyeing a 1872 for sale locally for $1200. Not that I need it...

[J-Mech]

I've got like 21 garden tractors, or some silly number. I probably don't need all of them, lmfao.

[zippy1]

Thanks!
Been eyeing a 1872 for sale locally for $1200. Not that I need it...

That's cheap for a super. Go get it.

[Charlie175]

Question, I forgot to note when I removed the adapter plate from the engine, where the spacers go. I have 3 different sizes for reason. Does it need them? Looks to sit correctly on the plate without them

[J-Mech]

Yes, you have to have the spacers. Should be 4 total, and they should all be the same size. They go between the engine and the mounting plate. Engine mount bolts pass through them and there are 4. If they aren't all the same size, get new ones.

[zippy1]

Just put mine back together. As Jon said/wrote, they are ALL four the same length.
Something definitely wrong that ain't right, if you got three different lengths...

[Charlie175]

Thanks for the info. I guess someone else lost 2 of them. I made duplicates and it is now mounted.