jd450 no pull in reverse

[kirkl]

Hi all I have a jd450 that needs a lot of work but my main focus right now is working on the reverser as it does not pull in reverse I have hooked a gage up to the screw hole underneath the bung cover ontop of the transmission and in drive i get about 180 psi (i think it has been a few months since I was last able to work on it) but when I put it into reverse I get 0-10 psi so my question is what are the usual problems that cause this to happen also I've heard that alot of people who have this problem do an oil change and filter change and that fixed their problem so I plan on doing that first anyways thanks for any help!!

[Jim B]

Good pressure in forward, low/no pressure in reverse would lead me to look for a leak or seal failure in the reverse clutch system. Cleaning the sump and cleaning/changing filters won't hurt but I don't think that will fix yours.
Jim

[cordlesscarpenter]

Hi all I have a jd450 that needs a lot of work but my main focus right now is working on the reverser as it does not pull in reverse I have hooked a gage up to the screw hole underneath the bung cover ontop of the transmission and in drive i get about 180 psi (i think it has been a few months since I was last able to work on it) but when I put it into reverse I get 0-10 psi so my question is what are the usual problems that cause this to happen also I've heard that alot of people who have this problem do an oil change and filter change and that fixed their problem so I plan on doing that first anyways thanks for any help!!

Were you able to get to the bottom of this problem? I have the same problem, well, very little power in reverse after about 30 minutes. She'll back up fine on flats or downhill but try taking uphill in reverse... forget it (but she'll go up a hill in reverse when she's cold). My engine oil pressure drops to about 25psi around this time as well, does yours?

[cordlesscarpenter]

I had this same problem, as stated in the last message, turns out my engine clutch needed some adjustment... now she is cutting dirt better than ever with the power one would expect from a machine this size. Oh, and I can even go up hill in reverse now! So thankful that it was just a few minor and quick adjustments to transform it into the beast it is now.

[Bond007taz]

I had this same problem, as stated in the last message, turns out my engine clutch needed some adjustment... now she is cutting dirt better than ever with the power one would expect from a machine this size. Oh, and I can even go up hill in reverse now! So thankful that it was just a few minor and quick adjustments to transform it into the beast it is now.

cordlesscarpenter , what did you do for the engine clutch to get your reverse operational again?!

[cordlesscarpenter]

Basically, when I would press on the clutch pedal, the throwout bearing would completely disengage, allowing me to shift like normal but when I lifted my foot, the throwout bearing was not releasing the clutch itself towards the engine "enough" to get complete engagement with the engine. I simply adjusted the clutch so that when I let out the clutch, the throwout bearing would release far enough to fully engage with the engine (plus a little more) .

Your steering clutches work in a very similar manner. They are always engaged with your final drive until you pull back on, say the right stick, the throwout bearing is then thrust into the three fingers of the clutch plate in one direction which in turn levers your clutch pack (single friction disk for the engine) in the opposite direction (away from engagement), the clutch's friction disk plates are now able to rotate independently from the steel plates now that the pressure meshing them together has been released. The still engaged left track can now continue to more forward turning around the "free spinning/disengaged" right track.

** Pulling back on a steering stick is delivering the same mechanical action as pressing the engine clutch pedal to the floor only the clutch for the engine is a single friction disk and not 18 or so friction disks and steel plates like inside the steering clutch drum.

When I pressed my engine clutch pedal to the floor it would disengage quite easily because the throwout bearing was ALREADY applying partial pressure to the pressure plate fingers, then my foot to the floor completely disengaged it from the engine but when I let my foot off the clutch pedal it would return to its relaxed state (which should be fully engaging with the engine) but it wasn't returning "far enough" and essentially leaving the connection between the transmission and the engine only "partially engaged" and the clutch would start slipping, getting worse the longer I used it.

The adjustment, if memory serves right, is on the left side of the top of the bell housing, look under the rubber bung plug on the left you'll see an adjustment bolt, adjust this in or out to reach your desired pressure plate engagement. I believe the right side rubber bung plug will give you access to grease your throwout bearing.

If you cannot adjust it to get proper adjustment, it is possible that your clutch's friction disk is worn and needs replacing put that's unlikely seeming most people with H-L-R trans will only use the use the clutch (disengage the clutch) when shifting between 1-2-3-4 gears and when starting the engine (or creeping up on something I suppose), everything else is done with the H-L-R stick. Using it is the only time it would wear (unless it is slipping, then it is practically wearing any time your machine is under load which may very well mean any time you are moving if it is that loose of an engagement.

I hope this helps, let us know how it turns out. The difference for me was night and day (expected) I just didn't think about it when I initially diagnosed the problem and was thinking more along the lines of transmission failure instead of looking a little earlier in the line of "transmission of power" between the engine to the tracks to make sure the trans was getting power in the first place.

[cordlesscarpenter]

Kirkl, How did everything turn out?

[Jim B]

It would be interesting to know. He may have browsed the site, but he hasn't logged in since Dec. 1, 2020.

[cordlesscarpenter]

Well, if it didn't help him, I'm sure some poor sap will be along in the future who will benefit from the thoughts we leave here. Then he'll read this post and chuckle once he realizes HE is the poor sap