450C HLR

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TexasJD
40C crawler
40C crawler
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Joined: Mon May 05, 2014 7:21 am

450C HLR

Post by TexasJD » Mon Aug 04, 2014 7:04 am

Finally had a chance to check the pressure on the transmission pump. Set the transmission in neutral started it up and the pressure hit about 110 at 1800 RPM. I put three washers in the regulating valve and the pressure did not move. I put in two more and still no movement. I put in one more shim and at that point I had a hard time getting the cap to catch the threads. Finally got the threads to catch but still no improvement in the pressure. I have a suspicion the valve may be stuck. Having never seen one apart other than in the tech manual I don't know how much travel is in the valve. I ran out of time and did not have a chance to work the machine as that might free up the valve. Any suggestion appreciated.

Thanks.

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DrLoch
1010 crawler
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Location: Mebane NC

Post by DrLoch » Mon Aug 04, 2014 1:08 pm

I'm assuming your talking about the clutch valve adjustment it sounds like you aren't doing something correctly.

Look here: http://www.jdcrawlers.com/messageboard/ ... um.php?f=8

Here is another explination

Speed of shift is a relativley easy adjustment. Pull the left floorboard out. There is a rubber plug there. pop the plug out and you will find a 5/16" nut on a threaded rod sticking straight upright. I use a 3/8 ratchet with a 1/2" deep socket on a short extension. To do it right you will need to put a guage into the pressure tap hole. This is located between the steering levers on the cast top cover. There will be a " drum bung " there . remove the bung plug. Inside you will find a 1/8" pipe plug with a 3/16 allen head.I use a dab of grease on the allen when removing the plug. This plug is on an angle, pointing forward. Install a guage with a 1/8 nipple . A 250 lb guage will work fine.Adjust the pedal free-play to about 4 1/4" from top of pedal to where the throw out bearing just touches the clutch fingers. Put the 4 speed into the neutral position between 3rd and 4th gears.Lock the brakes down.Start the machine, ease out the clutch pedal to make sure the 4 speed is in neutral. You can now start adjusting the HLR speed of shift. I usually back off the adjustment till the pressure drops off a bit. Then I turn the adjustment in till the pressure goes to maximum psi. Turn it a bit more till the pressure just starts to drop off [ 5 to 10 lbs ]. You will be real close now. Try the speed of shift with the 4 speed still in neutral at about 1/2 throttle. The gauge will show a lag between high and reverse . when you have it close, put the 4speed into 2nd gear and try it out. If it's still fast, turn the adjustment in 1/4 turn at a time till it's comfortable. It should just suck you out of the seat slightly going high to reverse . don't make it too " lazy " or too slow. This could cause overheating because of slippage. If it's too slow back off the adjustment 1/4 turn at a time. Usually when it's adjusted right, you can push the clutch pedal down 1/2" and the pressure guage will show a slight increase in pressure . The book can be a little intimidating . Go with the above and you should be OK. If you don't feel confident doing it yourself , print this page and take it to your mechanic. Oh , the pressure should read 175 to 185 lbs. . If after doing adjustments the pressure isn't up to snuff, under the right floorboard is a rubber plug. Under the plug you will find a cap of the pressure control valve.[ A penny is good for about 12 to 15 lbs.]

I would remove the shims you have in there 1st and then go through the procedure. If the clucth valve adjustment isn't correct the pressure will not increase by adding the shims.... ask me how I know :?
450C Track Loader
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TexasJD
40C crawler
40C crawler
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Joined: Mon May 05, 2014 7:21 am

Post by TexasJD » Mon Aug 04, 2014 2:47 pm

Thanks Dr. The Tech Manual is a little lacking.

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DrLoch
1010 crawler
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Post by DrLoch » Mon Aug 04, 2014 8:08 pm

TexasJD wrote:Thanks Dr. The Tech Manual is a little lacking.
Indeed it is..... . I found these instructions and adjusted mine, major difference in how the hydraulic clutch engaged. Right now mine is too abrupt so I'll go back in and adjust it again then I'll check the needle valve. It may have been screwed out by the previous owners to crutch the slow engagement that I was seeing. Like it states, when you put the gear change in neutral, between 3rd & 4th and the HLR in forward or reverse when you adjust the clutch valve you will see the pressure move once the pressure gets to it's highest indicated pressure that will be what your relief valve is set at. I did the same thing, added shims with no rise in pressure, then I re-read the instructions. Once I got the adjustment right the pressure came up and I ended up removing the shims I added. Also, once you have it set when you go from forward to reverse with the HLR lever (gear shift still in neutral between 3rd & 4th) you will see the pressure drop and then rise again. The motor will also load for a second as the clutch pack clamps and rotates the mass up to speed in the trans. I'm not sure but I believe I could use that shift time to adjust the needle valve to lengthen the shift time a little. Shift time is shift is shift time in terms of how fast the pressure falls and rise again to engage the other clutch pack. With the gage installed I should be able to adjust the needle valve and see a change in the fall and rise time.... in theory.... we all know about theory when it comes to these things. Mine is abrupt enough to spin the tracks on my gravel driveway when doing a forward to reverse shift without using the clutch valve. That I believe is too aggressive. I was making due, now I'm in the process of changing hoses and repacking the bucket cylinders. Once I'm done with that I'll lift the floor plates and play with the adjustments again.

Good luck, let us know how it works out for you.
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LMBE
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Re: 450C HLR

Post by LMBE » Sun Oct 15, 2017 7:29 pm

I am working on a early 450 SN in the low 105000. The manual states the pressure should be 140-150, I am getting 145-150 When put in forward or reverse the pressure drops to about 20 and stays ( machine does not move although seems to start)
My manual states when I depress the clutch 1/2 -3/4 " the pressure should rises a little 5-10 psi . This one drops to 80psi.

I was thinking I was going to attempt to do the clutch adjustment.
Any other suggestions would be welcome.
Also the write up by jdemaris says it should be 175-180 ?

Thanks,

Larry

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CuttingEdge
2010 crawler
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Re: 450C HLR

Post by CuttingEdge » Mon Oct 16, 2017 3:36 am

I am not familiar with a 450C, but I am assuming it has a hydraulic filter. I would change that first. My $6.50 filter cured 90% of my bulldozers problems.

If I seem to be condescending, I assure you I am not. Sometimes it is the simplest things that stop these machines, and it is best to start with the easy stuff and work inward.
I have no intention of traveling to my grave in a well manicured body; instead I am going to slide into heaven with a big power turn, totally wore out with busted knuckles, jump off my dozer loudly yelling, Woo Hoo, another Shepard has just arrived!

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