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ex300-3c mistracking and slow swing

J

johnnyboy

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Jan 31, 2012
Messages
125
Location
canada
Okay now I understand the SA pressure. Not sure if it is only p mode that does it but when in p mode right track dropped revs to about e mode and yes problem does follow pilot when switched, and think it does this in all speeds. Sorry I never got a chance to do cycle time on tracks but did the other day
right 0:25
left 2:08
Thanks for the help, will have to buy you some beer if we get it fixed
 
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K

KenAl

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Mar 30, 2007
Messages
194
Location
north
Rpm will drop if in slow travel mode. Here is the funny thing, when operating the travel lever left or right, as I explained before, the pilot signal oil gets blocked off and builds pressure and the travel pressure switch reads the signal to tell the PVC that travel has been operated. So in saying that it should not matter that you swapped the pilot lines as the signal is not from the pilot lines but from the spool blocking the signal line. As I understand the signal comes from the travel pressure switch on the valve bank. Just to prove that, swap the wires from the 2 travel pilot sensors under the cab and then try it again.
Also on your time cycles, get a swing cycle time. 3 revolutions from a running start. This is the same pump as the left travel.
Has there been any attachments or other valving put on this before? Any history on how this problem came up? All of a sudden? Was the valve bank ever repaired?? Did someone have to unstick a spool ever before? Did anyone ever have all the spools out? Please please please say no to the last one.
 
J

johnnyboy

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Messages
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canada
There has been problems with this machine along time. No other valving and beleive machine started with right track not wanting to stop turning thats why the front pump was changed and that didn't fix it, so I think uncle said it was a issue under cab floor sticking pilot or something. Then the left track started acting up but they've been working it anyway. The operator said if you lower revs it will start working again and then jack the R's up and it's good for a bit. And its only got 7000 hours so I don't thing anybody messed with control valve but can't be sure. As for the swing I will do cycle but it is slow until machine is warmed up. Is it possible the regulator on pump is not set up right.
 
K

KenAl

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Mar 30, 2007
Messages
194
Location
north
Anything is possible with the problems you are describing. (Regulator)
The lowering of the RPM then raising it and it works for a while, suggests to me port plate separation on the pump. You said they were new or rebuilt?
The swing being slow until it warms, up then its good :Banghead got me on that one. Sure sounds like a combination of problems.
 
J

johnnyboy

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Jan 31, 2012
Messages
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Location
canada
I wasn't quite accurate when I told you that lowering rpm's would make it work right, it was actually changing work modes from m1 to m3 or 4 and when doing this the pressure increases on the line running from shuttle valve being fed and activated through solenoid valve #1 and stayed at 300psi for some time even when going back to M1. Where does neutral passage oil enter control valve and where does it exit and is this same circuit as auto idle and what should neutral oil pressure be. Also nobody can understand why switching pilot lines from left forward to right forward didn't switch track function accordingly. Which control lines should I be taking off at pump to check for oil flow and what should there be?
 
D

danc

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Mar 11, 2009
Messages
89
Location
ireland
there's a lot of funny stuff going on. you mentioned a old issue track running on and not stopping and the pump was changed?:confused:

was the sticking pedal valve repaired, I'd be checking for internal leakage within this pedal unit. i can't see either how swapping the lines hasn't shifted fuction. Is it possible that some pipes are not fitted in their correct location with all the works previously.

I had an issue a long time ago and to rule out pumps I got an extension hose made up to swap the pump lines (main and displacement pilot line), I only needed extend the front as the rear pump reached the front pump. No difference so I knew both pumps were matched. You obviously have to swap electrical connectors etc..
 
J

johnnyboy

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Jan 31, 2012
Messages
125
Location
canada
Yes both pumps were changed on the advice of mechanic and hydraulic shop said they were both worn so don't know they didn't help anything. And found out last night he has owned this machine from brand new so nothing was really touched except pumps and cylinders. I think under cab was full of mud and ??? that got cleaned out and seemed to be better from what I understand as far as right track is concerned. Still can't wrap my head around the pilot line switch on control valve having no effect.
 
K

KenAl

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Mar 30, 2007
Messages
194
Location
north
Back again to square 1. Take all 4 travel pilot lines off the vale bank. Put gauges in them. (4). Use your travel and watch the pressure build up and make sure that only one is getting pressure while activating only one travel function. Try your M1 mode and rabbit and turtle speed. Make sure they all effect or don't effect the engine rpm in the exact same way. If there is a difference, swap the travel pilot pressure senders under the cab.
 
J

johnnyboy

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Jan 31, 2012
Messages
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canada
I pulled control valve today, wasn't to bad did it in 5 hours. There was just to much funny stuff going on. Also switched forward travel pilot lines and they did change tracks so that was a wild goose chase, I guess I should of confirmed that myself the first time but my uncle was running it and its his so what can you do. I did swing cycle and time was 1:19 boths ways p mode. One other thing I discovered while I had it out of the shop was the arm was running both pumps in and out also bucket stops in and out when pulling arm in and bucket stops when booming up, bucket in also stops when left side is in air and traveling but travel speeds up the more you try to roll bucket in. Please tell me that this is all control valve related because that would suck if I pulled it for nothing. I did go through checklist in manual for troubleshooting internal checkvalves inside valvebank and seemed to be more than one leaking, but there was really no symptom that best described behavior so not sure how reliable that is. And did swap the pressure sensors under cab and now auto idle seems to be working as well.
 
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K

KenAl

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I would have done a lot more testing before yanking the V/B. You have what seems like numerous problems. Good luck
 
J

johnnyboy

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canada
Well there was a couple machanics that told him that was the move to make on it and have been spending alot of time on it. Any thoughts on the 2 pump stroke when arming out? I also found stuck spool on "sb" of solenoid valve 1.
 
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J

johnnyboy

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Jan 31, 2012
Messages
125
Location
canada
So we split valvebank and found a couple checkvalves pounded abit and the aux spool was pushed upward about 3/64" and stuck in that position but a couple taps from bottom side and it free right up. So would be that 3/64" on the spool be enough to disrupt flow sense? because it was pretty low before.
 
Y

yatesy

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Feb 21, 2012
Messages
6
Location
australia
Seems to me like a flow issue and having a common pump supplying the two affected functions is the first place to check, are the pumps genuine reconditioned units? Have they been flow tested after repair? Is the pump control pressure correct for both pumps? Is pump case drain flow to high ? . Dont get too deep too quick first check all filters/screens/oil. Let me know what ya reckon.

Yatesy.
 
J

johnnyboy

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Jan 31, 2012
Messages
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Location
canada
yatesy said:
Seems to me like a flow issue and having a common pump supplying the two affected functions is the first place to check, are the pumps genuine reconditioned units? Have they been flow tested after repair? Is the pump control pressure correct for both pumps? Is pump case drain flow to high ? . Dont get too deep too quick first check all filters/screens/oil. Let me know what ya reckon.

Yatesy.
Click to expand...

The pumps were done by reputable place, but don't know if they were flow tested. How do I check pump case drain and how to adjust? And as far as pump control pressure that is where the problem is I beleive. The flow sense is 300psi on front pump and 100psi on rear pump at idle work mode #1, but rear flow sense goes to 300psi when changed to work mode 4 precision. The valvebank is going back in today with new springs and o-rings and I still have gauges to troubleshoot if needed. Any and all help is appreciated.
 
J

johnnyboy

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Jan 31, 2012
Messages
125
Location
canada
Anything specific because I will have to get them from work today but should be back home in 6 or 7 hours.
 
J

johnnyboy

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Jan 31, 2012
Messages
125
Location
canada
PVC FAULT Codes

So I reinstalled valvebank with no change in performance, but did manage to pull fault codes from PVC
4
25
26
27
28
33
35
36,
is there any way to erase these codes without Dr.ex because I believe some of these are not current, I would like to generate new codes to work with. Please respond
 
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