Colt Case Ingersoll Garden Tractors

I just changed the hydraulic oil on my 446 which is used only in the winter with a snow caster. The lift circuit has always made a squeal when lifting the caster. I’ve had this GT 30 plus years. I figured if I could tighten the adjustment screw a little the squeal would stop. After removing the lift adjustment screw cap I see the adjustment screw has no slot in it. I checked the travel adjustment screw and there is a slot in it. Has anyone ever seen an adjustment screw without a slot to turn it? Harry

Harry wrote: ↑Sun Mar 19, 2023 12:43 pm I just changed the hydraulic oil on my 446 which is used only in the winter with a snow caster. The lift circuit has always made a squeal when lifting the caster. I’ve had this GT 30 plus years. I figured if I could tighten the adjustment screw a little the squeal would stop. After removing the lift adjustment screw cap I see the adjustment screw has no slot in it. I checked the travel adjustment screw and there is a slot in it. Has anyone ever seen an adjustment screw without a slot to turn it? Harry

Harry,

I may be wrong, but I seem to remember that you use a hex bit on that one.

Bob

Thanks for the reply Bob. The adjustment screw cap threads unto the adjustment screw. It’s a threaded round screw more like a fine thread 7/16” bolt. Harry

Is it possible that the PO had it apart and put the screw in backwards ?

When you bring in PO’s into the equation anything is possible David. I’m not sure how I could even get it out without buggering up the threads. I was thinking of double nutting the screw, but only about 3/8” is out side the valve body. As you know it’s in a very difficult area to maneuver. Harry

with the spring pressure against it, it's only a little bit beyond finger tight as far as moving it. Perhaps you can get a good condition pair of needle nose or bent angle needle nose pliers on it?

Or one of those tiny cute little sets of channel locks?

Bob

Thanks for your reply Bob. I didn’t want to take it out and didn’t want to possibly cross thread the adjustment screw. Then I would have to take it out. I was afraid of the spring and ball coming out and losing the ball. Maybe if I jacked up the rear of the tractor, put it on jack stands, so it was pitched forward the ball and spring wouldn’t fall out. Just a thought. By the way Bob I do have two pairs of those cute little channel lock pliers. Harry

I was thinking of taking a small air operated die grinder with a small 2” disc on it. Reach ip in this very small area and cut a small groove in the middle of the threaded bolt. The try running a die over the threads to chase off any burrs. With a S-shaped screw driver I have, try adjusting the bolt. The more I procrastinate this the more ideas I come up with. Suggestions are always welcomed. Harry

@Harry I would give the die grinder idea a try. I have a Dremel with a 4ft whip which works for getting into tight places. grinding a slot in situations like this is my method of choice.

Lots of good ideas. I have a TCV from a 446 out in the shed. I'll have a look later tonight after the kids I find it very unusual to have an adjustment screw with no means of turning it. At the very least it should show signs of mutilation.

If it were me, it doesn't make any difference if it's forwards or backwards it's still applying pressure to the spring. So I would just make a slight adjustment up or down to make this squeal stop and put it all back together.

But as far as taking it out goes you have to apply a little pressure to it to get it to thread in because the spring is up against it. But there's zero danger of the spring and ball falling out. The ball is on way on the inside of the spring and the spring is about 2 and 1/2 in long.

Bob

I recall reading in the old forum that adding a flat to one side of the ball bearing will stop it from rotating and squealing. I never tried it but I do have the same problem at times on my 4016.

There you go

MattA wrote: ↑Sun Mar 19, 2023 9:58 pm I recall reading in the old forum that adding a flat to one side of the ball bearing will stop it from rotating and squealing. I never tried it but I do have the same problem at times on my 4016.

I'd want to have an extra ball bearing on hand, because if the flat gets rotated around where the seal is made then it won't seal. Then, as the "soup nazi said, "No pressure for you!!!" It'll be "all relief, all the time."

Bob

thebuildist wrote: ↑Mon Mar 20, 2023 7:28 am

MattA wrote: ↑Sun Mar 19, 2023 9:58 pm I recall reading in the old forum that adding a flat to one side of the ball bearing will stop it from rotating and squealing. I never tried it but I do have the same problem at times on my 4016.

I'd want to have an extra ball bearing on hand, because if the flat gets rotated around where the seal is made then it won't seal. Then, as the "soup nazi said, "No pressure for you!!!" It'll be "all relief, all the time."

Bob

I don't buy the ball rotating , I have heard the stem style squeal .
from research scientists
"The poppet valve is a fundamental component in fluid power systems. Under particular conditions, annoying “squeal” noises may be generated in hydraulic poppet valves. In the present study, the frequency spectrum of the squeal noise is obtained by analyzing the sampling data from the accelerometer mounted on the valve body. It is found that the flow velocity, pressure, and structural parameters have crucial effects on the properties of squeal noise, especially frequency. Larger valve chamber volume or lower backpressure leads to lower fundamental frequency of the squeal noise. An explanation for the squeal noise, as a result of Helmholtz resonance, is suggested and proved by experimental results."

DavidBarkey wrote: ↑Mon Mar 20, 2023 8:29 am
from research scientists
"The poppet valve is a fundamental component in fluid power systems. Under particular conditions, annoying “squeal” noises may be generated in hydraulic poppet valves. In the present study, the frequency spectrum of the squeal noise is obtained by analyzing the sampling data from the accelerometer mounted on the valve body. It is found that the flow velocity, pressure, and structural parameters have crucial effects on the properties of squeal noise, especially frequency. Larger valve chamber volume or lower backpressure leads to lower fundamental frequency of the squeal noise. An explanation for the squeal noise, as a result of Helmholtz resonance, is suggested and proved by experimental results."

Wow! @DavidBarkey that's a lot of multi syllable words used in one paragraph... Think I'm going to have to sit down with a and ask to stop for a while so I can digest your and interpolate all of your information...

As a mechanic I can confirm that "is suggested and proved by experimental results" actually means - Plug and Pray of existing components hoping that the very audible vocalizations of unseen but obviously present gremlins contained in said component will not be evident after the substitution of an identical component leading to increased operator comfort and decreased calls to the service manager...

He said, "Turn down the pressure and it'll get quieter."





Bob

DavidBarkey wrote: ↑Mon Mar 20, 2023 8:29 am

thebuildist wrote: ↑Mon Mar 20, 2023 7:28 am

MattA wrote: ↑Sun Mar 19, 2023 9:58 pm I recall reading in the old forum that adding a flat to one side of the ball bearing will stop it from rotating and squealing. I never tried it but I do have the same problem at times on my 4016.

I'd want to have an extra ball bearing on hand, because if the flat gets rotated around where the seal is made then it won't seal. Then, as the "soup nazi said, "No pressure for you!!!" It'll be "all relief, all the time."

Bob

I don't buy the ball rotating , I have heard the stem style squeal .
from research scientists
"The poppet valve is a fundamental component in fluid power systems. Under particular conditions, annoying “squeal” noises may be generated in hydraulic poppet valves. In the present study, the frequency spectrum of the squeal noise is obtained by analyzing the sampling data from the accelerometer mounted on the valve body. It is found that the flow velocity, pressure, and structural parameters have crucial effects on the properties of squeal noise, especially frequency. Larger valve chamber volume or lower backpressure leads to lower fundamental frequency of the squeal noise. An explanation for the squeal noise, as a result of Helmholtz resonance, is suggested and proved by experimental results."

In all sincerity, it does seem like if you had some kind of dampener on the ball that it would attenuate the harmonics and silence the squeal.

Maybe take an extra ball bearing, carfully drill it about halfway through with about a 9/64 or maybe 5/32 drillbit, and then silver solder/braze in about a 2" length of 1/8" aircraft cable. Then replace the normal ball with the "ball with a tail", with the tail running up the center cavity of the spring. It seems like that flexible steel "tail" would greatly dampen any squeal noise.

Bob

While I'm at it, you know the newer spring design tapers down a lot at it reaches the ball. The old spring design is just a cylinder, with parallel "sides", the new design looks like a funnel, (or a tornado). Same ball size, same cavity size.

I was curious why the newer spring tapers down. Maybe it helps with squeal?

Bob

you guys are I'm having a ball here

Eugen wrote: ↑Mon Mar 20, 2023 9:38 am you guys are I'm having a ball here

Agreed
You all have me laughing out loud this morning!

thebuildist wrote: ↑Mon Mar 20, 2023 9:33 am While I'm at it, you know the newer spring design tapers down a lot at it reaches the ball. The old spring design is just a cylinder, with parallel "sides", the new design looks like a funnel, (or a tornado). Same ball size, same cavity size.

I was curious why the newer spring tapers down. Maybe it helps with squeal?

Bob

Conical or tapered springs have a variable rate of compression - my thought would be that you get a quick "pop off" followed by greater resistance as pressure against the ball and spring is increased...

Did a little more Googling on Conical Springs...

"Vibration: Resonance and vibration is reduced because conical springs have a uniform pitch and an increasing natural period of vibration (instead of a constant) as each coil bottoms."

Whew... I've learned something new for today.... Parents always said I should learn something new every day -
today's mission accomplished !

So @Harry needs to install a newer version spring. I presume they're still available.

Bob

Harry, I have a TCV sitting on my shelf that you can have if you need it. Let me know ...

Ray

I would never believe a simple post about a squeal in my hydraulic lift circuit would promote so much controversy. The 446 with the snow caster has been put away until I get time to dig into it. I moved my 646 into the shop for servicing to get it ready for summer use. No hydraulic squeal here guys, Sorry! Harry

Harry, just remember that ANY post deserves analysis.

Stop!

Well, on edit, I only read the first page and missed the other 2 when I replied. Adjust accordingly.

Do not do any of the things mentioned. Please.

You are entering a new area of knowledge. There is a Case service manual for the hydraulic system. If it is not in the files section and you cannot find it, I do have it on disk. But, I have to find the disk.

You picked the wrong time to solve your issue. The squealing is because your hydraulic oil warms very slowly in the winter and stays on the tick side of its range. The solution to that is running 0w40 synthetic oil. You already changed your oil. But, it will be well worth doing it again. I would even exercise the midlift when the drain is out to get the 15W40 all out.

There is a pressure range that is specced to your TCV. And that means there is a port that you can add a hose with a pressure gauge. The adjustment is the flat screw that is inside of the threaded outer threaded tube the size of the acorn nut which is only there to keep the dirt out of the adjustment area.