To those who have performed the engine ISO mount cradle mod
 

To those who have performed the engine ISO mount cradle mod - what % of vibration did it remove? I am trying to see if it's worth performing or not. If the majority of those who did the mod say it helped reduce vibration - then I'll go for it.

Thanks for your time.

It doesn't reduce vibration at all. It keeps the rails from tearing up the oil pan. :Forgot:

It's worth performing. I have a whole pile of oil pans that will have to be built up, machined off and the threads repaired. Otherwise, they are just junk.

as Jon said the purpose isnt to reduce vibration but to save the oil pan. without the cradle mod the only thing holding the two rails together is the aluminum oil pan, it will eventually pull the treads out of the pan as well as crack the corners off.

I did the cradle mount mod on my 1650 this winter. In my experience, I think the tractor vibrates a little more now! Has anyone else who has done this mod seen some increase in vibration? The K341 is a shaker for sure, and mine didn't appear to have the balance gears.

What else did you do while the engine was out?

Since I did my 1650, it runs so smooth, you can hardly tell it's in there.

That would be nice! It smooths out at full throttle, but it's no Cadillac!

Here is the list of everything I did this winter:

-Pulled engine to replace crank seal that was leaking.
-Engine cradle mod
-replaced oil pan gasket
-new flex discs. 1 in front, 2 in back
-new hydro fan
-welded and filed trunion
-replaced cork gasket
-did the front-end pivot pin Grade 8 bolt mod
-thrust bearing on steering

After all that, the engine still leaked oil--badly. Pulled the engine again to find the crank seal dry as a bone (it was leaking previously). What was continuing to leak was the bearing plate gasket. In fact, some of the bolts were very loose.

-replaced bearing plate gasket and shimmed
-re-replaced crankshaft seal

I think that's it, aside from other little things like fixing lights and painting the grill, foot treads, rear-end cover, and drive shaft.

Improper timing and carb settings as well as not having the rubber mounts tightened properly will cause it to shake more than it should.

I think my timing and carb setting are fine. The engine runs great and just as it did before I worked on it. I torqued the rubber mounts to 20 ft-lbs, I believe. Is that proper? Perhaps they should be tighter?

The common thought is that 20ft lbs is too tight. Thighen the nuts until about 2 threads show above the nut. Try it and do small adjustments from there.

Thanks. I will check that out. Do you think loosening up those nuts will help my vibration situation? Also, when I reinstalled the engine, I put new metal lock nuts on the mount bolts. Do I need to replace those again if I back them off a little, or should I be okay?

There is no mention of new motor mounts, were your old mounts in good enough shape to reuse?

I should have mentioned that the previous owner of this tractor replaced the motor mounts right before I bought it from him, so they are practically brand new.

Way too tight. On my 1450 I used Ny-Lock nuts and tightened them down to the point where the rubber bushings were just snug. No problems....!!!

:ThumbsUp:

Okay, good to know. I need to check the bolts, but I think about 2 threads are showing through at 20 ft-lbs. Is tightening these motor mounts along the lines of tightening the flex discs on the driveline? Just make it snug, don't torque down on it?

Did you replace the centering bushings for the driveshaft? Bad mounts (which they all have at some point) will wear the driveshaft ends and bushings out of round. I would try loosening the mount bolts as suggested, but it may be driveshaft related.

Bill

Berwil,

I did not replace those bushings. The ends of my driveshaft did not have any noticeable wear. I felt the bushings before reinstalling, and everything seemed okay, but I didn't inspect them. I actually didn't consider them for wear.

I will certainly loosen up my mounts. Seems to me that may be what is causing the vibration. It's not violent or anything, but it does seem to be a big more rigid.

Just snug up the motor mounts then?

Grab the driveshaft at the front and try to move it up and down. If there's much movement the front mount needs replaced. Reusing the nyloc nut should be ok.

That is correct. As mentioned, check the drive line.

Ok please by all means correct me if im wrong, but i hear people complain about engine vibration at low idle and it goes away at high idle????? The engines were designed to be ran at HIGH idle this is how they COOL!!! It's not a Porsche + mowing should be done at high idle anyway. JMHO

The engines were designed to run at WOT or 3600 RPM's.

When I'm using the tractor, it runs wide open. If I stop to get off and do something I'll bring it down to an idle. For it being called a Quietline, I don't really consider it very quiet, at least not right next to it. Maybe my neighbors can't hear it. Unfortunately, mine is missing the muffler shroud, so perhaps that is working against me.

i will tell you this; my 1250 after total rebuild and all new mounts shakes...even gets some small rattles at about mid throttle.. but the amazing thing is that i have noticed, especially like if my son is riding on it with me, its the only tractor i can actually talk to him in a regular tone of voice and be heard...its a single...they shake..but maybe you do have something wrong...youll know when you get it...good luck