Cat 988B heating issue

[ajginger]

50 ton jack ..... take the weight off the tyres...... heck..... I may need a lot bigger jack to get that little pin out then. I only have a 20 ton bottle jack.

 

[kshansen]

I'm pretty sure you can get the rams out of the cylinder on the left by steering it all the way to the right. One point that may not be obvious is that it will help to let the ram come out if you remove the hose from the back of the cylinder so you are not fighting suction from that end.

One idea to keep in mind for those tapered pins. If you at some time find one where the pin has come loose and wore the tapers it can be difficult to repair that taper, not sure how one would do it in the field, what I recall having done on a couple machines was to bore the holes for a straight pin. Believe we had a bushing made for the top side as that is bigger than the pin. Then once that bushing was installed line bored it and the bottom bore to accept a straight pin. Not a perfect solution but sometime you do what you have to do!

 

[ajginger]

Just an update on the steering cylinder repair :

Used a 20 ton bottle jack to remove the pins out. Didnt need to flog the lugs with a hammer, they just popped out. Front one took almost all 20 tons of pressure before it popped loose though.

Found out the fuel tank side rod/piston cannot be removed while the cylinder is still pinned. There isn't enough room beside the fuel tank to swing the rod end out far enough to get it past the front half of the loader.
( Must remove the whole ram )

I used the front pin lugs to hold the ram while we removed rod/piston.
Also used the front lugs, the tray of the work vehicle & a peice of cut timber to hold the rod while I broke loose the nut that holds the piston.

Looking at the difference, I think the hydraulic tank side steering cylinder may be able to remain pinned in the machine while it is repaired. There seems more room between the the ram and the hydraulic tank to be able to swing the rod out far enough.
The cylinder is not leaking on that side so wont be rebuilding it yet to find out.

 

[kshansen]

If only doing one side at a time I seem to recall on some machines all you had to do is steer all the way say to the right then work on left side. Then if you need to do the right side put the left one back in and steer machine to the left then work on the right.

Also if you block off the lines to one cylinder you can steer the machine using only one cylinder as long as on smooth surface, but it will actual react faster when it only has to supply oil to the one cylinder.

 

[ajginger]

If only doing one side at a time I seem to recall on some machines all you had to do is steer all the way say to the right then work on left side. Then if you need to do the right side put the left one back in and steer machine to the left then work on the right.

Also if you block off the lines to one cylinder you can steer the machine using only one cylinder as long as on smooth surface, but it will actual react faster when it only has to supply oil to the one cylinder.

I tried to get the rod out with the machine articulated all the way but it was still about 4-6 inches too close to get the piston out of the cylinder. The fuel tank stops the cylinder from being pulled out enough.

 

[kshansen]

I tried to get the rod out with the machine articulated all the way but it was still about 4-6 inches too close to get the piston out of the cylinder. The fuel tank stops the cylinder from being pulled out enough.

Well it's been a decade or two since I had the pleasure of doing that job so might have been thinking of some other Cat!

 

[ajginger]

Well it's been a decade or two since I had the pleasure of doing that job so might have been thinking of some other Cat!

I thought for a moment it was going to work.... but no show.
By the looks of it I think the hydraulic tank side steer ram might be able to be re-sealed with it still pinned. The hydraulic oil tank looks far enough out to pull the rod past the front end.

 

[ajginger]

G'day all.
I am getting more tourque converter slippage lately than usual. I have heard that there is there a way to retrieve some torque by adding a shim to the converter clutch control valve at the end of the variable torque lever cable.
Is there anyone here thhat has done this ?
Thanks in advance.

 

[Nige]

Have you tried setting the correct adjustment on the control cable as a first step.?
Also I guess it would be a good idea to check that the cable is well-lubricated and is not binding.
See attachment.

 

[ajginger]

Thanks Nige. Yes I have adjusted the cable and it seems to be sliding inside the sheath ok.

 

[Nige]

In that case the next step would be to get into the Sequence & Pressure Control Valve and check all the springs to see if they are "tired". Most likely they are, I'd speculate they are probably original.
After that test all the converter pressures, especially the Impeller Clutch Pressure.
See attachments.

 

[ajginger]

Thanks for that help Nige. For some reason I cant download the files you uploaded. I have a complete workshop manuel for the old girl so I should be able to find it in there.

 

[Nige]

You need to be on a PC or a laptop and download them to the desktop. Some smartphones don’t like them it seems. They are only Adobe pdf.