John Deere 450G Brake

[daverd4]

Just bought a 1988 John Deere 450G yesterday 4630 hrs in really nice condition. All new undercarriage original owner. When I was testing it out i noticed that the brake peddle took a little more pressure to apply and went down to fare I thought. It's the long brake peddle in the middle with stick steering am I correct that that is a Direct Drive Not Torque Converter drive. I've gone through the forums and can't find anything much about this. I did read in one that the peddle should pump up when you take the park brake off not sure if that correct. And is anyone familiar with maybe they just need adjusting and if so how? Haven't got a shop manual yet. Any help would be great thanks.

 

[mg2361]

Need a serial number.

When I was testing it out i noticed that the brake peddle took a little more pressure to apply and went down to fare I thought

Make sure all the linkage is free from binding and corrosion.

If you just apply the center brake pedal with a machine with steering levers the brake bands apply but the steering clutches remain engaged. So stopping the machine with just the pedal won't happen. If you pull both levers to apply both brakes then the steering clutches will disengage allowing stoppage.

Haven't got a shop manual yet.

Make sure it is Operation and Test Manual TM1403. You definitely need this to adjust the brakes properly. Operators Manual OMT163974 would be of use as well.

 

[daverd4]

So by pressing the left disengage peddle and hitting the big brake peddle you still need to pull back on the steering levers also to stop? I found a OEM Tm1404 manual hope that one covers this machine they sure aren't cheap but a lot better then reprints. I've owned two D4D Cats and a Case 450 this is my first John Deere. Thanks for the help. The serial number is *T0450GF744789*

 

[daverd4]

 

[mg2361]

So by pressing the left disengage peddle and hitting the big brake peddle you still need to pull back on the steering levers also

No, pressing the left pedal and the center pedal will stop the machine. Just pressing the center pedal by itself though won't stop the machine.

 

[daverd4]

Ok Thanks that's what I thought. The big brake peddles seems to go down a long ways is it just hooked to some band brakes that can be adjusted up? And will that OEM TM1404 manual work for this Dozer hope I didn't waste my money.

 

[daverd4]

Ok new at this John Deere manual thing but figured out that TM1404 are for the same machine as TM1403 it looks like. Is the TM1403 included in the TM1404 manual don't want to waste money on duplicate manuals. Thanks

 

[mg2361]

No the TM1404 does not include the TM1403 or vice-versa.

TM1403 is the Operation and Test manual which will have all the diagnostic procedures, adjustment procedures and schematics. TM1404 is the Repair manual which is how to disassemble and assemble everything except the engine which is yet another manual which I think for your machine with the 4276 engine would be CTM4.

 

[daverd4]

Got the JD 450G home yesterday. Bought over $500 worth of OEM Manuals for it but they won't be here for a week. I have a question about the decelerator peddle when I start the Dozer the rpm's go up to about 1200 with out holding the peddle down. Shouldn't it idle down to 500 or 600 with the hand throttle at the slowest position. Wonder if someone adjusted the linkage to make it do that.

 

[daverd4]

Got the decelerator peddle fixed it was the end of the cable came apart and was bending when pushed all the way to slow position. All my manuals won't be here for a week free shipping isn't fast. Have a couple problems maybe someone can help with 1st the bulb check lights do nothing when key is turned to that position. 2nd the long brake peddle in the middle does not pump up when the engine is started like it should. Any help would be greatly appreciated.

 

[mg2361]

1st the bulb check lights do nothing when key is turned to that position

That spot between on and start? Check the R01 black wire from the monitor to the key switch. When in the bulb check position the key switch provides a ground to the bulbs and the logic module.

2nd the long brake peddle in the middle does not pump up when the engine is started like it should.

It won't come up until the park lock lever is raised. Even then if there is enough wear in the park lock linkage that it does not "kick" the FNR lever (shifter) into the neutral slot then the brake pedal won't raise. Same thing if there is enough wear in the shifter linkage that the shift spool does not shift into it's first detent. Are you saying it does not come up at all even when the shifter is in the neutral slot?

 

[daverd4]

I'll check the black ground wire first Thanks . And yes the pedal doesn't come up at all in neutral F or R. The pedal goes to the floor sitting or
moving. Maybe not the floor but it has about 5 or 6 inches of travel with very little brake.

 

[mg2361]

The pedal goes to the floor sitting or
moving. Maybe not the floor but it has about 5 or 6 inches of travel with very little brake.

Check all the linkages real good first. Also on top of the transmission case towards towards the front and the outside on both sides where the bellcranks for the brakes are there should be a pin sticking up with a spring on it. Are both of them in the up position or stuck in the down position?

 

[daverd4]

Is this under the floor boards or the seat and battery box. Not sure what I need to remove. I just checked again and my manuals should be here Wednesday that will sure help.

 

[daverd4]

I figured it out took the back panel off cleaned out a 5 gallon bucket of dirt. No one has been in there for awhile. Took the bolt out that hold the seat and slid it back kind of handy.

 

[daverd4]

Well after vacuuming over 5 gallons of dirt out I found what you were showing me in the picture. But they look nothing alike here's a picture of mine.

 

[daverd4]

Is it possible that the brake bands can be worn out with only 4600 hrs. And is it a major job to replace them on a 450G lever steering?

 

[mg2361]

here's a picture of mine.

You might have to remove the sheet metal from above the track. The pins I am talking about are closer to the track side of the transmission top.

Is it possible that the brake bands can be worn out with only 4600 hrs

How does it steer? How far do you have to pull the levers to steer (in inches). The brakes on those machines are fairly durable. I would wait for the manuals and make sure all the adjustments are spot on.

 

[daverd4]

Ok thanks I'll pull those bottom covers and look . I will measure but you have to pull a long ways on the levers.

 

[daverd4]

Pulled the bottom covers cleaned out all the dirt and finally found the spring loaded pins you were talking about. They are both in the up position one was in oily dirt and the other was not. Soaking it in penetrating oil . Are they important other then towing? Next can't find any slop in the linkage at all it is very tight . So I finally pulled the big plugs were the auto adjusters are bingo the right side has no adjuster and is backed off . So I guess the next step is pull the back cover off and hope I can get to and find the lost parts. Any guidance would be great . Totally explains all the issues I think.