I've been reading about other quietlines with bad shaking issues. I'm compiling a list to check. Lots of people say these just shake and that's what they're known for. I know what "normal" shaking feels like from Kohler iron. This is quite a bit more than normal. So motor mounting and drive line are the two big places to check.

My question is this, why are these known to be shakers? I had a 1210 briefly that I drove around before pulling the M12 out to use in my Jacobsen, and it had the same mounting system, except it had the cross supports at the front and back. It did not shake at all. It does not shake in my Jacobsen either bolted right to the frame. Also, my 123 has a K301 in it, it shakes some but not terrible. So, it definitely can't be normal to shake like the hood is going to fly off. Maybe I should go to the smooth running M12 in this tractor if all else fails.

My 1250 shakes a bit at idle but that’s about it. It has the cradle mod and aftermarket rubbers from CC Specialies, new driveshaft and flex discs

My QLs don't shake any more than the WFs. Except the 1650, which shakes at low speed. All have the cradle mod and new OEM iso mounts. Even the 1650 smooths out at speed.

Just using the 1450 the other day for the first grass cutting of the season. I thought it wasn't running at full speed, it was so quiet and smooth. I had to put the laser tach on it to confirm it was running close to 3600 rpm. When properly adjusted and the grill and hood snugged down, and the muffler and air duct all buttoned up tight, QLs are actually pretty, well, quiet.

I have investigated the driveline, it had some wobble in it. I had a very good condition engine side coupler and very good condition rubber rag joints so I took it apart and installed those. The driveshaft is perfect, no wobble, but the engine still shakes pretty hard. One thing I noticed is one of the engine mounting holes is stripped out, so only three of them are able to be drawn down tight. Maybe that's it? So, I pulled the engine out again. This is a K241 with an aluminum flat bottom pan, and I happen to have a cast iron flat bottom pan on the shelf from a 100 that's in good shape. So I plan to swap that over and reinstall the engine.

While I have that engine out, I tried swapping in my M12AQS engine, and it won't work. The flywheel shroud is a little bigger than the K series, and it hits the iso mounts which won't let it sit down all the way to bolt into the rails. I would need about 1/4" spacer or something under the engine but that would probably throw off the driveshaft alignment, which I don't want to do. Or I could eliminate the iso mounts somehow, which I probably don't want to do either.

So the current plan is to put the K241 back in with the cast iron pan and run it, and work on tuning the engine and see if I can get it smoothed out.

After that the next project is a trunnion repair. It's pretty badly worn and the spring is WAY off center. It's really hard to find neutral.

I finally got the M12 in there. I realized the K had indents in the shroud to clear the iso bolts. So I made indents in the mag shroud and it fits. I did the cradle mod also, and I ordered new iso mounts because even though they look pretty new they’re a little chewed and compressed from the bolts being drawn down tight. The issue now is the M12 has a 1 1/8” PTO shaft. So I need to do something about a clutch.

Attachment 99506

Well being that a QL has an electric clutch that would be an easier fix than one on a WF. I've had Ariens machines with 1-1/8 dia cranks while the twin cyl powered machines had 1-1/4. When I swapped out a KT for a Magnum twin, the Magnum had an 1-1/8 crank I had a good clutch left from a single cyl powered machine and that clutch hub went right on. Glad to see that you were able to get the Magnum in there good info for later use.
I have a pair of wide base Magnum singles here, one of which I know is drilled for both pans. I have an extra aluminum cub pan here.
Another interesting combo to try.

Winner winner chicken dinner! I have another PTO on the shelf and I got to looking at it thinking it looked similar. It had a 1 1/8” bore. So I pulled the pulley off the rotor and it looks the same. So I swapped the rotor over and we have a 1 1/8” shaft PTO for the QL.

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Coool!!!!!!

Well now another issue popped up. I noticed the top of the shroud is jammed against the firewall. It is more square than the original engine. I haven’t run the engine yet but I wonder if that’s going to be an issue. Everything is bolted in fine but it’s gonna rub for sure and probably vibrate.

Time for the Ralph Kramdon... hamma, da hamma, hammer!