645 Loader Questions

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   So I bought this loader and have been going over it today.  I fixed a few lines that were rubbing, got the fuel shut down cable adjusted right, greased it and put some brake fluid in the master cylinders.  Seems as though now when I put on the brake pedal the brakes work and the transmission also seems to shift to neutral.  It did not do this before I put the brake fluid in the masters.  Is the transmission disengaged by brake fluid or by air pressure?  The transmission oil looks a little on the dirty re color to me.  What oil should be in this transmission and where would I get a filter for it as I would like to change them both.  Strange thing is, when I looked at it to buy, it would shift into high forward and for some reason now it does not seem to want to do that just stay in low when I move the lever to the high position.  If the transmission is shifted with brake fluid is there any chance of the brake fluid getting into the transmission as that would not be good, and the master cylinders must have leaked out to somewhere.  I did not see any leaking out of the brake area, or maybe it would leak into the final drives (??) that also would not be a good place for brake fluid.  Or should I be using hydraulic oil rather than DOT3 brake fluid?  Final question for tonight, is there any difference between a 645 and a 645B, I have found a service manual advertised for a 645B but can not find one for a 645, although a parts manual is available?

Pictures hopefully tomorrow of her at work.

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Amos Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 11 Sep 2009 Location: Ontario Points: 1301	Post Options Post Reply Quote Amos Report Post Thanks(0) Quote Reply Topic: 645 Loader Questions Posted: 05 Apr 2014 at 9:09pm
	So I bought this loader and have been going over it today. I fixed a few lines that were rubbing, got the fuel shut down cable adjusted right, greased it and put some brake fluid in the master cylinders. Seems as though now when I put on the brake pedal the brakes work and the transmission also seems to shift to neutral. It did not do this before I put the brake fluid in the masters. Is the transmission disengaged by brake fluid or by air pressure? The transmission oil looks a little on the dirty re color to me. What oil should be in this transmission and where would I get a filter for it as I would like to change them both. Strange thing is, when I looked at it to buy, it would shift into high forward and for some reason now it does not seem to want to do that just stay in low when I move the lever to the high position. If the transmission is shifted with brake fluid is there any chance of the brake fluid getting into the transmission as that would not be good, and the master cylinders must have leaked out to somewhere. I did not see any leaking out of the brake area, or maybe it would leak into the final drives (??) that also would not be a good place for brake fluid. Or should I be using hydraulic oil rather than DOT3 brake fluid? Final question for tonight, is there any difference between a 645 and a 645B, I have found a service manual advertised for a 645B but can not find one for a 645, although a parts manual is available? Pictures hopefully tomorrow of her at work.

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Eric B Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 09 Feb 2012 Location: British Columbi Points: 888	Post Options Post Reply Quote Eric B Report Post Thanks(0) Quote Reply Posted: 05 Apr 2014 at 10:27pm
	The trans disengaging is by air as far I know, there is an air flip switch in the cab to turn this feature on or off, and you don't have to worry that brake fluid gets into the final drives or transmission, it could however leak from the wheel cylinders and mess up your brake shoes and drums. If you check the inside of all the wheels you may detect brake fluid seeping out of a drum. Re trans filter...try the best you can to see any numbers on it for bringing to a parts counter. Any out fit that sell or service Allison transmissions should have info to help you. Years ago the owner of a Allis dealership recommended 20w engine oil for the trans. as 10w was apparently recommended from the factory. Personally in warm weather conditions I would even use 30w engine oil (thicker oil gives you better metal to metal protection). Try to follow the linkages to the transmission for the shifting to work in high gear in case it needs some adjustment. Hope you're having fun with your new toy.
	Currently- WD,WC,3WF's,2 D14's B. Previously- I 600,TL745,200,FL9,FR12,H3,816 LBH. Earth has no sorrow that Heaven cannot heal!

Amos Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 11 Sep 2009 Location: Ontario Points: 1301	Post Options Post Reply Quote Amos Report Post Thanks(0) Quote Reply Posted: 06 Apr 2014 at 5:36am
	The transmission oil I was talking of changing appears to be like hytran or dexron based oil. I was wondering if it should be power fluid 411 or can I run caseIh hytran in it. I keep the hytran for a couple tractors with power directors and a backhoe is all. Is the filter the one in the canister on the right side of the engine up behind the hydraulic tank?

Kcgrain Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 24 Sep 2009 Location: Wisconsin Points: 767	Post Options Post Reply Quote Kcgrain Report Post Thanks(0) Quote Reply Posted: 06 Apr 2014 at 12:46pm
	If the 645 is like the 745 you have a brake line that runs around to the right side of the tranny there is a valve there that dumps the transmission pressure. You might get brake oil in the tranny, because there is a seal on that valve, that is probably wore, dry, or shrank over time, thats what our 745 did, and when the brake fluid magically disappears yet there are no visible leaks thats where it goes. There is a shut off, for that feature, which is actually annoying, on the 745 its to the left of the driver seat, on the back wall, one way shuts the oil off from going to that cut out. On our 745 we replaced all the brake lines, removed that valve and switched it to electric, with a toggle switch on the dash.

Amos Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 11 Sep 2009 Location: Ontario Points: 1301	Post Options Post Reply Quote Amos Report Post Thanks(0) Quote Reply Posted: 06 Apr 2014 at 5:02pm
	Kc, yep, I already found the air valve of which you are referring. Makes sense what you say as I can find no leaks externally at the brakes or lines, and I am sure that dot3 brake fluid is not good for the transmission. You wouldn't happen to have a picture or the electric part you used to switch it over? May not work on 24 volts though, as I was not wanting to change over to 12 volts with a new starter on the engine. Shoot, looks like I am going to have to fix that right away too.

Amos Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 11 Sep 2009 Location: Ontario Points: 1301	Post Options Post Reply Quote Amos Report Post Thanks(0) Quote Reply Posted: 06 Apr 2014 at 7:26pm
	After driving it three concessions in low forwards, well one concession in low forwards and two in reverse (its faster than forward low), I discovered that the parking brake handle must be right at the bottom of its travel in order to let the forward reverse lever move to its full travel. A swift step down from my work hoe solved the issue. Some oil on the linkage and mechanism in the future will work wonders I am sure Edited by Amos - 06 Apr 2014 at 7:30pm

Eric B Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 09 Feb 2012 Location: British Columbi Points: 888	Post Options Post Reply Quote Eric B Report Post Thanks(0) Quote Reply Posted: 07 Apr 2014 at 12:52am
	My apologies for the misinformation with the cut-out circuit not leaking into the transmission. I never had the problem on the 745 so I never studied the design enough. As long as you don't activate the trans cut-out switch you won't have any brake fluid going into the tranny. You really only need that for short temporary stops to speed up the hydraulics without taking it out of gear manually, mostly for loading trucks or feeding hoppers which you may not be doing any way. The oil question you mention ..... probably all the oils you mention will work fine. Where I live we seldom ever get cold temps so I always used 30W engine oil in the trans. In most older Caterpillar machines with powershift transmissions the manuals call for 30W engine oil and I've never had a problem with a Cat trans. What's good for the goose should be good for the gander as they say
	Currently- WD,WC,3WF's,2 D14's B. Previously- I 600,TL745,200,FL9,FR12,H3,816 LBH. Earth has no sorrow that Heaven cannot heal!

Kcgrain Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 24 Sep 2009 Location: Wisconsin Points: 767	Post Options Post Reply Quote Kcgrain Report Post Thanks(0) Quote Reply Posted: 07 Apr 2014 at 3:23pm
	The brake fluid doesnt actually leak when your using it, it leaks when your not, becasue there is no pressure it just slowly goes by the seal. I can get you a picture if you want to PM me your email or cell number, I bought the valve at a local hydraulic place that handled parker products, and the coil can be bought in 12 or 24V. If you dont plan on using the loader much, youd be better off switching it to 12V, for some reason 24v wants to fight between the two batterys till its dead, so we have to unhook one battery so they cant fight, I plan on putting a disconnect so we can kill it when we dont use it, which here its just a big toy that can lift almost anything it puts its mind to, but fun to use when we need it. You could plug the line off completely and not put a valve in at all if you want, that feature is for reving the engine up to lift the booms faster when your loading trucks, without shifting to nuetral, but on ours its more of an annoyance than anything, if you want to sneak into something gently, every time you touch the brake it disengages the transmission, and if your loading someting or unloading something heavy it a huge pain in the .......

Amos Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 11 Sep 2009 Location: Ontario Points: 1301	Post Options Post Reply Quote Amos Report Post Thanks(0) Quote Reply Posted: 07 Apr 2014 at 8:49pm
	Kc, already put a disconnect in the machine to solve the battery issue arising. I can only imagine what a 745 would be capable of doing. Here is an idea I had yesterday, not sure if it will work or not, but I could just put hytran in the master cylinder that runs the front brakes and the clutch disconnect valve, if it leaked into the transmission then there would be no contamination. The only leaks I have found so far are from the master cylinder for the back brakes. The level in the front brake cylinder seems to be staying up. I want the clutch disconnect working, even if I have to overhaul the valve, if I can get the parts for it that is. I use it for every shift and must have used it when dumping brush into the pile today at least 50 times, not to mention when working with helpers on the ground around the machine. Any idea on the difference between a 645 and a 645B? I would like to have a service manual and the only one I can find is for a 645B?

Kcgrain Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 24 Sep 2009 Location: Wisconsin Points: 767	Post Options Post Reply Quote Kcgrain Report Post Thanks(0) Quote Reply Posted: 08 Apr 2014 at 9:43am
	645B was newer, and had some minor advancments, like a soft shift transmission, and I think the engine had a few up grades as well, but the basic machine is the same. The valve has a real simple seal system that can easily be rebuilt, and the parts are available, becasue that transmission was made by twin disc, I believe. You cannot run hyraulic oil in the brake system, its too heavy in cold weather, and you wont have brakes. Even dextron gets heavy in the winter. If the system isnt leaking fluid, than your not leaking into the transmission. Its a pretty simple system to fix, any Fiat Allis dealer should be able to get you the parts, we bought a whole new spool that did the disconnect a few years ago, and it was available, and not expensive, you can also try MinPar for parts.