Newbie question for the snowcat whisperers

[MyOwnPrivateIdaho]

Hello everyone. Been lurking for a few years now, have a winter snowcat access only property in Idaho. Wouldn’t have it any other way, but having reliable transport is an absolute must.
Bought a 1970 1450 super imp. It has a completely restored track system. Belts, grousers, wheels, it all seems sorted.
I went through the engine top to bottom, too much to list. Really happy about the availability of parts, ease of working on it, thousands of you tube videos and obv the experienced expertise shared on this forum.
Thanks to everyone for their input to the forum, I’m a motor head, but new to snowcatting. Learning quickly, lots of good information here.
Question for the experienced snowcatters…
As I said, everything seems tight and right. However, I’m getting a pretty serious vibration/shaking upon acceleration. Vibrating enough to cause my plug wires to vibrate off my distributor cap lol. Noticed that the guides were hanging pretty low with the new belts breaking in, and they were hitting the support bars for the leaf springs, did a track adjustment, tightened it up, everything clears now, was expecting that the vibrations would go away.
No.
Next thought was U-joints/drive shaft. Checks all the boxes for the symptoms. Pulled the drive shaft, took it to the shop for U/joints, rebuild and balancing. Installed it, expecting a dramatic improvement in the ride. Better, but it still will rattle your fillings loose on acceleration.
I realize that this is a steel box on a steel frame on tracks and it’s not going to ride like a Cadillac. I also realize that my driveway is a hard pack cat trail currently without recent snow, this obv affects the ride, but interested to hear everyone’s experience with the noise and vibrations in regards to normal operation? Am I chasing my tail, it is what it is, or is there possibly something not right…..?
Appreciate any input from the Cat whisperers.

 

[Melensdad]

How deep/soft is the snow when you rattle off the wires from the distributor?

I sold my snowcat, but never experienced anything like you are describing, and I had a different model/brand, so my experience may not be relevant. But the type of shaking you are describing is nothing like what I experienced. Different terrain would cause various shaking of my entire snowcat. A cornfield is much rougher than a bean field, deeper snow is much smoother riding than hard pack, etc.

But honestly what you are describing seems more like a mechanical unbalance than a terrain issue.

You've already pulled and balanced the drive shaft, I'd be looking at the other drive components to make sure they are all aligned and balanced because that seems like the place to start looking.

 

[MyOwnPrivateIdaho]

How deep/soft is the snow when you rattle off the wires from the distributor?

I sold my snowcat, but never experienced anything like you are describing, and I had a different model/brand, so my experience may not be relevant. But the type of shaking you are describing is nothing like what I experienced. Different terrain would cause various shaking of my entire snowcat. A cornfield is much rougher than a bean field, deeper snow is much smoother riding than hard pack, etc.

But honestly what you are describing seems more like a mechanical unbalance than a terrain issue.

You've already pulled and balanced the drive shaft, I'd be looking at the other drive components to make sure they are all aligned and balanced because that seems like the place to start looking.

Thanks for the reply, please elaborate on “other drive components”
It seems to be the drivers side mostly, and seems to originate there, makes me think it’s track related, the entire wall shakes, the door rattles, the gas tanked is mounted inside on that side and shakes also, maybe that’s what’s making all the racket, will look at its mounting tomorrow, really thought the rebuilt driveshaft would solve the problem, checks all the boxes for symptoms, maybe making something out of nothing. It’s basically a tank. Not sure what my baseline for performance is with no experience. Just want to be sure I’m not damaging something.
May look into wheel bearings next….?

 

[MyOwnPrivateIdaho]

Thanks for the reply, please elaborate on “other drive components”
It seems to be the drivers side mostly, and seems to originate there, makes me think it’s track related, the entire wall shakes, the door rattles, the gas tanked is mounted inside on that side and shakes also, maybe that’s what’s making all the racket, will look at its mounting tomorrow, really thought the rebuilt driveshaft would solve the problem, checks all the boxes for symptoms, maybe making something out of nothing. It’s basically a tank. Not sure what my baseline for performance is with no experience. Just want to be sure I’m not damaging something.
May look into wheel bearings next….?

Btw, it’s melt freeze icy cat road right now, maybe I’m just overreacting and it’s just conditions, but again, I don’t know what my “working correctly baseline” is, looking for input. My dog is very unhappy with the noise and shaking lmfao

 

[MyOwnPrivateIdaho]

Btw, it’s melt freeze icy cat road right now, maybe I’m just overreacting and it’s just conditions, but again, I don’t know what my “working correctly baseline” is, looking for input. My dog is very unhappy with the noise and shaking lmfao

Wheel bearings, bent spindle? Bent frame? Old sprockets, new track…? Seems acceleration based, other driveline components…? Not experienced with track systems, or drivelines, just brainstorming, thanks in advance for any input forum gurus.

 

[MyOwnPrivateIdaho]

Sorry boys, talking to me is like drinking from a firehose, what about cab mounts? Possible I have a broken bolt or attachment so that it’s not secure?

 

[Melensdad]

Wheel bearings, bent spindle? Bent frame? Old sprockets, new track…? Seems acceleration based, other driveline components…? Not experienced with track systems, or drivelines, just brainstorming, thanks in advance for any input forum gurus.

YES all those, I'd start with bearings and spindles as those seem like thing that would be more magnified by speed.

 

[pixie]

Did you check or replace your engine mounts ?

 

[Idaho IMP]

Welcome to the group, you must be in North Idaho or McCall as we have ZERO snow here in the Wood River Valley.
Id remove your doghouse and run the engine. Look for/feel for any sizeable vibration. Check all of your plug wires and ensure they’re in proper firing order.

Seems like what you’re describing is from driving on a hard surface. I doubt it’s a track issue as they rotate slowly. It’s possible you have a broken engine mount but I doubt it. Otherwise, pray for snow and give her a rip in softer conditions. Keep us posted

 

[BoyToys]

Did you check or replace your engine mounts ?

That's the first place I would look.

 

[MyOwnPrivateIdaho]

Welcome to the group, you must be in North Idaho or McCall as we have ZERO snow here in the Wood River Valley.
Id remove your doghouse and run the engine. Look for/feel for any sizeable vibration. Check all of your plug wires and ensure they’re in proper firing order.

Seems like what you’re describing is from driving on a hard surface. I doubt it’s a track issue as they rotate slowly. It’s possible you have a broken engine mount but I doubt it. Otherwise, pray for snow and give her a rip in softer conditions. Keep us posted

Thanks everyone, appreciate the sounding board and good information. Been tinkering for a while now, going through every system, and have learned a lot. Win win.
I’m a motorhead, the engine is completely tuned, but I have never worked on a tank before lol. Fortunate to have new tracks from the previous owner.
Update, my previous multi post rant was right after I installed the balanced drive shaft/ujoints and it wasn’t handling well, but it seems that it just took a little time for the tight bearings to break in, it ran a lot better the next day, and has run smoothly and reliably since. It was definitely the U joints, just flew off the handle when it didn’t work immediately.
Ugh yes, the icy cat road that is my driveway. Have broke a few grousers, no substitute for having a bag of ice melt in the back, but it gets me up and down the hill every day. It has three sections with 45 degree slope climbs and it’s always an adventure. Amazed at how capable it is pinned in 2nd gear. Hauls my water up the hill to fill my cistern, 2 50 gallon drums full, chugs right up.
Everything seems spot on. Hoping that Vintage means that they don’t make them like they used to instead of Vintage meaning that it will break down all the time.
Love my IMP, life would be a lot harder without it, so far so good.
Hope you get some snow soon Idaho
imp. I live in Driggs. Weird winter. -20 to 40 in a day….? Crazy stuff.