ISO mounts questions

rdeyoe · #1 08-19-2015, 08:07 PM

Tearing into my 1450 now. I knew the mounts were terrible when i bought it, the engine was trying to exit the tractor. Got the motor out (pretty easy with only one bolt in the oil pan), and saw the flattened lower ISO bushings. I'm thinking the uppers may be usable, pretty old though.

I've already read just about everything on these mounts and options for them. I studied around for a while on options (solid, car bushings, etc.), not being able to put the newer Cub Cadet mounts in. I happened upon some isolation mounts on ebay (not the aftermarket ISO bushings someone's selling). I measured my cradle holes...seem about 7/8" on the ID and the OD from the old mounts was 1-1/4". These mounts are 3/4" ID and 1-1/4" OD with 3/8" steel bushing. They're recommended for a 3/8" mounting plate, so i figured clamping them down to the 1/4" cradle would expand them a bit. I heard the newer Cub mounts were kind of hard, so I asked the seller for the durometer scale of his. He replied that they're a 40 shore scale....pretty soft (does anyone know the scale on the originals?). Got them in today and they are soft....about as soft as my originals. Plus, they were only $20 for all four, worth a shot.

Some pics of the mounts free, loose on the cradle and mounted to the frame. I clamped them up with some larger washers on the top side that has ID larger than the steel bushing. The seemed to clamp up very nicely. The space on the lower side is a bit less than 1/2". I have the bolts tightened all the way down to the shank.

Has anyone tried these? Other opinions? Can anyone give me the height measurement of original mounts? It's going to be a while before I can get the motor back in to test, but this cradle seems to have good isolation and firmness. Have to repair the oil pan from all the banging around it did in there and get the cradle mod done....

bkw3614 · #2 08-19-2015, 09:30 PM

First of all, I think Quietlines are great tractors!

Replacing your ISO mounts is the best thing you can do for your tractor and its power plant. when I replaced the mounts in my 1250 Nightmare, I used genuine Cub Cadet replacement parts. I was unaware of your choice, but they look decent to me; better than the Moog replacements that so many use, and seem to have decent luck in getting them to work.

One thing you didn't mention in your project is to make the recommended engine cradle modification. this keeps the ISO rails from twisting independently and causing stress to the oil pan. From this forum's technical section, here is the modification plan: http://www.onlycubcadets.net/forum/s...ead.php?t=4630. This is worth every bit of the modest cost. Either having a welding shop make the repair, or doing it yourself, if you have a welder, it is worth every bit of the effort.

That 1450 is a wonderful tractor! Please keep us informed as to your results. There is all kinds of help here to get it up and running again. All the best to you and your project.

Brian Wittman

zippy1 · #3 08-19-2015, 10:20 PM

Quote:

Originally Posted by bkw3614

First of all, I think Quietlines are great tractors!

Replacing your ISO mounts is the best thing you can do for your tractor and its power plant. when I replaced the mounts in my 1250 Nightmare, I used genuine Cub Cadet replacement parts. I was unaware of your choice, but they look decent to me; better than the Moog replacements that so many use, and seem to have decent luck in getting them to work.

One thing you didn't mention in your project is to make the recommended engine cradle modification. this keeps the ISO rails from twisting independently and causing stress to the oil pan. From this forum's technical section, here is the modification plan: http://www.onlycubcadets.net/forum/s...ead.php?t=4630. This is worth every bit of the modest cost. Either having a welding shop make the repair, or doing it yourself, if you have a welder, it is worth every bit of the effort.

That 1450 is a wonderful tractor! Please keep us informed as to your results. There is all kinds of help here to get it up and running again. All the best to you and your project.

Brian Wittman

His last sentence he mentioned the cradle mod...

rdeyoe · #4 08-19-2015, 11:40 PM

Hehehe...yeah, bkw. I've read over several of your posts on all kinds of stuff to fix. I've already picked up so much from your Nightmare posts. I really like the simplicity and power of this tractor. Since it's my first, and I'm not planning on collecting a bunch, i wanted something that I could use and expand on. The 1x50 models were the ones I wanted. Glad I chose this one...

I got bored / curious right after I posted this, so I hit the shop for a couple of hours to do the mod. I had the 1.5" x 0.25" bar stock. Pretty simple welding (I have a mig / stick welder but I'm no pro with it) so I zapped it together real quick and threw the mounts together. It's very strong now. Firm, yet it does give so slightly. I stood on the cradle, and even though I don't have much clearance on the belly pan, maybe 1/4", i couldn't make it touch. I've read somewhere, somebody used some 5 hp air conditioning or refrigerator compressor mount but never really mentioned the mount numbers...so i'll give these a shot: Universal Isolation Mounts

Some progress pics. Someday she'll be all prettied up with new paint, but for now everything has to get functional. I had to weld around the pan mount bolt holes, there were some deep gouges where the pan had hammered some washers the PO had put between pan and cradle. Lots of grinding and flattening going on. Going to space those snubbers out too.

ol'George · #5 08-20-2015, 08:44 AM

Don't mean to piss in yer porridge, but hope you bolted the iso rails to your oil pan or a like jig, before you welded the cross brace to them.
If you didn't, all the stars and planets have to be lined up perfectly or your bolt holes will not align with the pan, and/or the brace might interfere with the pan sump.
You'd not be the first to have that happen.
Best of luck!!

rdeyoe · #6 08-20-2015, 10:43 AM

Heheheh, yeah. Thanks ol'George. I've read up on the iso bar mod and did put my oil pan in place before welding. Actually, that one's going to be another project. The oil pan (aluminum) had been sitting on the bars for quite a while so the bolt bosses are beat towards the outer edges, not flat across. When I bolted the bars on, they wanted to tilt to the pan bosses, so I couldn't crank them tight. I put the bolts in but left them a little loose. I clamped the brace on tightly so that it would square up the bars to each other...the pan was just keeping the bolt holes lined up. When I welded the brace in, i did one edge at a time letting it cool down before starting another section so that distortion would be minimized. After it was welded, i could still turn all the bolts with very little pressure. The complete cradle lined up fine with the iso mount holes also, there's a little room to play with on those though.

On the pan, I plan on brazing some material to it to build up a bit, flattening out the bosses and drilling for some steel keyserts. There are threads in the holes, but they're very loose threads. I'll loctite and lock washer the bolts in the mounts to keep those suckers from coming out anymore. Got this pic that kind of shows the non-flat bolt boss compared to the cradle bar. All four are about like this but I couldn't really get good pics. Front right pan mount, no bolt in it here...just sitting on cradle bar:

budscub · #7 08-20-2015, 12:08 PM

HELLO Rdeyot,
I have a 1450 and a 1650,
The 1650 was my fathers so I have been very familiar with it, and have always thought that it rattled too much and shook more than to my liking. Those 16hp are real thumpers, l0l.
I had previously did the rail mod and installed the "e pay snubber "ISO" mounts" it helped, and I was satisfied with the results, Well atleast at that time. Now, fast forward to Fall of 2013,
I ran across the 1450 and it has the dual hydraulic stick. Anyway, when I redid the engine mount on it, I did the rail mod and was able to reuse the top original iso on the bottom and replaced the uppers with shock bushings. All I can say is wow that thing is smooth.
SO , now I have learned that a quietline really can be quiet and smooth, I am no longer satisfied with the 1650 shakes. With a new found encouragement, I loosened the bolts on the brand x iso, it does help by not as smooth as it can be. Now usable, but I will still be doing something to improve it.
Now to your original post, I too have contemplated using those. Seems very plausable that they would work. My concerns with that mount is the final mounting height, concerning driveline alignment. My thinking was to order some abrasion resistant rubber isolation washers to put under them to bring the rail height up to near original, and use a second isolation washer between the top mount and rail to close the 3/8" stock down to the rail thickness. Now I have not gotten to the point of taking the measurments of an installed ISO, The uninstalled mounts are aroung 7/8 uncompressed vs, the 1/2" of these "versa-style" mounts.
So after all this rambling, I am interested in the results of your project. Looking forward to following your progress. Congratulations on your 1450, You will really appreciate and enjoy it when you get it correct. You see alot of varying opions on the quietline machines, having had them in both in neglected mechanical condition and in correct operating condition, I can understand the varying opinions. I feel that anyone that " hates on" the quietline have not operated one in correct condition.

rdeyoe · #8 08-20-2015, 12:36 PM

Thanks buds. I'm curious about that too. I was looking around but can't find the installed measurement of the original lower mounts either (if anyone knows and can post measurements / pics, that'd be grrreeeeeaaaat). I wanted that to determine the universal installed height. I know the originals are around 7/8" uncompressed, but there's no real physical "stop" to keep them from being crushed smaller...hence the sinking to the frame when they get bad. I was thinking that that may be the reason a lot of people recommend the "1 or 2" threads on the lock nuts, to keep the mounts from any more pressure (or to increase the rebound with less clamping force)...i dunno.

I have two 1/2" ID x about 1/8" thick washers on the top of the upper bushing. They push the top bushing down below the stop of the center steel bushing. It seems to only crush the upper bushing more and not affect the lower height much, if at all. The bolt is cranked all the way down to the shank also. As they are right now, they're probably as tight as they can get. That should give me a lot of release space if I feel i need to loosen them up. I stood on the cradle to see if they would sink. They didn't budge much with 170 lbs on them, figure the ~120 lbs motor shouldn't move them at all.

edit: I notice that my snubber spacing is at least 1/4" too high. I don't believe my frame or bars to be bent and I think the snubbers are original parts (another measurement for snubber thickness needed?). I think the snubber-frame spacing is supposed to be .06-.12". I might have twice that.

budscub · #9 08-20-2015, 02:27 PM

Well i will measure on mine that I used the original bottoms on, the snubber heights seem to be about right, but I haven't measured them. I was thinking that the one side of your rail looks to be bent upward, now thats just looking and comparing to my memory, lol for whats thats worth. I will check mine again to see if I see any upward swing in the end of the rail. I will check the snubber height on that same machine too. I believe the originals are pretty soft, stands to reason that the softer they are the lighter vibrations that can be absorbed rather than passed into he frame. When you look at the load ratings of the "Versa" mounts, keep in mind that the rating would be (X4), being the engine weight is distributed across the 4 mouning points, So, say a 40 pound rated mount, using 4 pieces in theary could support 160#'s. Like I said before I have been contemplating getting these and some additional Iso washers to build up a mount to get me the results I want. Then, after seeing the dofference the originals made in the 1450, the questions becomes, experiment or bite the bullet and go originals. However, my understanding is that the new style original design are slightly harder than the 1st generation style.

rdeyoe · #10 08-20-2015, 03:10 PM

I was wondering about that bend myself. Didn't notice it with the bars out, but i do see it in the pics...in fact, on both sides. I guess the only way i'll know anything for sure is to get in back together and run it. That may be this weekend sometime, although i have two cars in my shop that need to get running again. Any measurements or pics you can get will be a big help! Maybe i'll notice something that needs correcting before i get the motor mounted. I think if i need to raise the cradle up, i can fab some spacers to go under the lowers. The oil pan work is going to be next. Might make a new thread for that work...