ISO Mounts
 

Tonight I replaced the ISO mounts on a 1650 that was supposed to be a parts tractor for my 129. My plans changed a bit so I'm fixing both up. Anyways I used the TRW equivalent to the moog bushings. (They were 4.99 vs 8.99 for the moog)

The stock lower bushings were completely gone. The uppers were in bad shape as well so I used the TRW for uppers and lowers. Uncompressed they are a bit taller than the stock setup so I had to use a little longer bolts. I snugged it up so two threads were showing and started it up. The thing vibrated like crazy, but the engine was no longer hopping around so I took it out in the yard for 10 minutes. After about 5 minutes it smoothed out a bit, but it is still pretty bad. Tomorrow I'm going to try tightening the mounts down a bit more to see what happens.

I guess while researching I noticed people said the moog type mounts shook pretty good. I guess I attributed that to an oversensitive operator. After trying them out for myself, I now know that it's not a sensitivity issue. I'll run them for a while to see if they break in and settle down a bit.

The test drive produced one casualty. One of the hydro fan blades broke off. After the fact I noticed they had a cotter pin on some adjacent linkage that seemed a bit long and if turned right could touch the fan. I'll take a closer look at that tomorrow.

Sounds like they needed tightening...was the engine jumping around or solid to the frame ?? You may also notice a sweet spot on RPM's that lessens the shake...


What were the part numbers on the TRW part ??

The Moog (or whatever brand) are stiffer than the Cub Cadet mounts. As a suggestion, as I have learned this from personal experience, get a "Ny-Lock" nut for the mounting bolts/ Only tighten to the point of being snug. The vibration of the motor has to be absorbed by the mount(s). If the mounts are too tight, it defeats the purpose.

If you had to use longer bolts, indicates that the geometry of the drive now is off because it is now raised up. As another suggestion, take Moog mounts and take some material off to the point where the dimension would be the same as the CC mounts.

:IH Trusted Hand:

I agree with Roland that the engine sounds likes its sitting to high which is also causing alot of undo flexing in the rag joints as it spin, creating more vibration.

I spent some good time smoothing my 1450 out after I gave it a makeover. I did use new CC mounts though. There are many factors in play that create vibrations. Its important to keep the drive shaft level. After some playing around I found by using a small magnetic level on the drive shaft (tractor not run of coarse) I snugged the iso mounts up until the shaft was pretty level, it did not take alot to do so maybe 10 -15 in lbs.

Also make sure your snubbers in front are adjust correctly, once you hang a belt on the pto they will help keep it level as well.

Time is your friend as well, as I got to 10 hours with the new rebuilt engine and mounts she really smooth out where you cant notice much at WOT.

Thanks for the replies guys. The TRW Part number is 18074. TRW parts also have a lifetime warranty. I've had good luck with them on my cars.

I don't think the height is too much of an issue. I think with the way the TRW mounts sit in the engine cradle they stand a little taller when they're not compressed. I tightened them down some more tonight and the vibration decreased a bit. I also noticed what I think a lot of my problem is. The two front bolts bolting the engine to the cradle are loose. I can't get them to turn in anymore either. I have the feeling that the threads are all messed up from the engine bouncing around for a few years. I was hoping to get away with not pulling the engine but it looks like I'll have to.

I'm debating on if I should just solid mount it. My father has a case 644 with a brand new retrofitted 16HP kohler in it. They guy he bought it from solid mounted it and I don't think it vibrates bad at all. Granted the case has a few hundred pounds on the cub which will help dampen it a bit.

On another side note I noticed that I have a head gasket leak on the front of the engine. So I'll have to fix that too.

I'm starting to wonder if this should turn back into a parts tractor...