Archive through August 28, 2012

[pbell]

Daniel,
<blockquote><hr size=0><!-quote-!><font size=1>quote:</font>

It dosen't vibrate very much @ idle or wide open but at mid range,where I like to mow,its pathetic.<!-/quote-!><hr size=0></blockquote>

If you read the Operators Manual on any of the IH built Cub Cadets (and it is printed in bold type in the manual that covers the ISO mount equiped models), it tells you that you should mow (or work/load the engine) with the engine at full throttle. The engine is designed for it, and it provides greater airflow across the engine to cool it. Even the solid mounted engines will vibrate some at "mid range".

 

[kfreeman]

On the Quietlines, I am with Gerry.

The cradle modification will not affect vibration. Without the mod, the two rails are rigidly fastened to the engine. The rails and engine should move as one. The cradle mod helps keep stress off of the engine mounting bolts if they loosen up. It also keeps the rails in proper orientation when the engine is out of the tractor, making engine installation easier.

The iso-mounts are not critical parts. If they are all the same height and stiffness, they will work. The weight of the engine will compress them. The amount of tightness on these bolts will not change the vibration issue significantly. Yes, changes in rubber stiffness or compression could have some minor effects on their ability to dampen vibration, but not major effects.

If you have huge vibration issues, I would look elsewhere.

Daniel, I would be mowing at full throttle, governed rpm. That is where everything was designed to run. That is where you get maximum cooling air flow. Under Edit: Yeah, like Paul said!

 

[wheinsohn]

I have replaced the engine mounts in my 1650 and last fall I took the balance gears out and added the cross brace to the rails. The engine vibrates a little at idle and more at about 1/3-1/2 throttle but runs pretty smooth at wot where it is supposed to be run at for mowing grass and other duties. It vibrates less than it did at wot but about the same at an idle than it did with the old mounts.

Don T, I have also added washers to my trunions and it does reduce the slow down and speed up when going down hills. It also adds to the thickness of the area that wears into the slot.

 

[bjamison]

Mercy - all this talk of these crap QL tractors, I'm wondering if the reason my 1650 doesn't cause me headaches is because it's still in pieces out on the patio...

 

[kmcconaughey]

Bill,

 

[vthomley]

The 1650 I have runs smooth at full trottle, its also fine at slow speed, but in between its not so smooth... Its a beast at full throttle though!!! Wow! this 1650 was a complete rebuild by a fellow forum member, he then offered it to me at a price I could not refuse, its my first and so far only QL tractor and its awesome. Here's a pic because pics are good!

 

[kide]

Don T:
You mean the Rag coupler I made out of a piece of conveyor matting back in the dark ages (BF/BC) HAS to be replaced??

Another thought on the vibration issue is that the rubber mounts cannot be too loose or the engine will shake at some speeds - undamped. If you've ever started up a small engine on the floor, you'll know that unless you restrain it with your hand, it'll dance across the floor at certain speeds - your hand is the damper, actually working like a shock absorber. I would think that if you don't follow factory specs, which I agree with Matt are a little suspect, the best way to tune the mounts for least vibration is tighten the all the nuts down a quarter turn at a time and test UNDER LOAD.. Tune for least vibration.

Added... I think it should be remembered that engine balance itself is a compromise, as the balancing is not perfect and better (and worse) at specific speeds. I think the 321 I'm going to build will have them thar added balance plates....

 

[dtanner]

Gerry Ide

No we are the same page, I did not want to confuse anyone so I used what Charlie's calls them on his site http://ccspecialties.org/clutch_driveline_rearend.html and he says they are called IH Cub Cadet Drive shaft flex coupling disc PN/ 722- , But dohicky has worked before

 

[wchockensmith]

thanks D.Tanner the local cub store tells me they are NLA I have a piece of Transmission Belting.you know the kind they would use on a steam engine to power a sawmill or thrashing machine it looks like it has enough reinforcement to hold up to the job

 

[bwittman]

I was able to get flex couplers for my 1250 from my local Cub Cadet dealer.

If a flex joint is to be made, I would want to use five ply belting rather than the usual stationary implement drive belt three ply.