D3B Clutch and cylinder rebuild

[AllDodge]

What's wrong with the valve you have? There's not much to it. It is a variable pressure control valve. Are you sure you have the stroke adjusted right?

As a non-expert I believe its so worn that even the O-rings are not sealing it up. I replaced all the o-rings and nothing is leaking outside, it must be doing it inside.

Connected the gauge on the output port direct and slowly moving the peddle and watching the piston move in/out andd I cannot get more then about 125 psi. This tells me its leaking internally

 

[Old Magnet]

Can you set up the valve to check with compressed air and observe leakage?
Did you check the springs? Should be a spec somewhere for the spring rate.

 

[AllDodge]

I have one of each type, and the roller is on the left side. Have old style with no roller on the right.

Dave, I do have 2 different valves but its not the real old one with just the plunger, both have the rollers, and I did remove during rebuild. The housing is a bit larger on the newer one. The one with the larger housing may be the 146 part.

What's wrong with the valve you have? There's not much to it. It is a variable pressure control valve. Are you sure you have the stroke adjusted right?

Just hooked the valve up to compressor and its leaking bad. Constant leak with rod full out and get worst as it goes in

Just noticed my compressor slowed down and stopped, think I need to fix it.
Hope its the motor and not the compressor, but didn't smell any smoke

 

[Welder Dave]

Regal couldn't get the valve? Nothing on Machinery Trader parts? I would think there's a few D3B/C or 931B/C sitting in wreckers yards. Price from Cat is crazy but if your machine steers properly won't have to worry about it again for a long time.

 

[AllDodge]

Talked to the parts guy at Regal and gave him all 3 part numbers and still no good. Yep the cost is up there but agree shouldn't have anymore troubles with that area. Only have the other 200 parts which are still 50 years old

 

[Old Magnet]

Check the dismantled machines list on Machinery Trader...
https://www.machinerytrader.com/lis...hines/list/manufacturer/caterpillar/model/d3b

 

[AllDodge]

I already ordered the part

 

[AllDodge]

Part could be coming in today and got to thinking about the difference in old/new. They are different sizes so making adjustment for the rod won't be that much, but the mount in a bracket. The bracket are different sizes, so the chances will also need another bracket is high

 

[AllDodge]

New control valve 1468034 looks just like one replaced on left side.
They have 1/8 NPT on top/bottom and AN6 ORB plugs on sides. Don't understand why and assume they just fill with oil from hydraulic system



Will need to shorten rod about 2 inches


Will need different bracket 8Y4021 which was able to get used from Boyd CAT for $27

 

[Old Magnet]

That valve is from a much later D3C, D3C LGP, XL Series lll Tractor.
s/n 6SL, 7XL, 9TS Machine. They have a lot more involved valve plumbing.

 

[AllDodge]

Good to know, guess I'm just lucky it also works on mine

 

[Welder Dave]

The new valve was first used on later serial numbers of D3B's in 1986, the same year as the machine in question. I posted that earlier in this thread but AD decided to go with a newer valve to match the other one that was replaced. It needs a different bracket and I don't know if it will require different linkage arms. Maybe it's an improved valve so is worth converting everything over?

 

[AllDodge]

Sorry if I misunderstood a comment, but I have not been able to get any other valve except the one I got. The original, and 2 other revisions were no where to be found, and I got the last one of this type in KY.

I didn't know it was the same as the left until it arrived

 

[Welder Dave]

OM gave a part to match the other one that had been replaced. I would think it's an improvement. It just sucks that's it's not a direct replacement.

 

[AllDodge]

Don't know what to say
Parts that came back from request from spareparts.com were at a minimum of 3 week wait from USA sources, and upon review they had some bad reviews. One in FL and other in WA, and read the FL takes paypal only and not credit cards which was a big flag for me.

Got another offer from Russia and was not going to take that one

So I looked for 5G0145, 5G8121 and one other CAT gave me (forget the number but was for D5 and larger tractor) and 146-xx and decided to buy the $1600 part

Once new part came in found out I need a different bracket. CAT found a used one for $27. Hope this all works because not fixing it means I have about a $12,000 paper weight

 

[Welder Dave]

It should all be fixable. Someone made the other new valve work so this one should to.

 

[AllDodge]

8Y4921 Bracket



Valve installed left side



Cut the rod down about 2 inches and threaded rod



All back together and placed dozer on a hill and in neutral it rolled a little but not much. So loosened the brake another half turn to let it roll easy. Turns much quicker

Will need to run a bit more but still has some issues in second and third gear, but is better. Probably just going to live with it. It does fine in first, just 2 and 3 does not have any power. Hey its a farm dozer

 

[Welder Dave]

2nd and especially 3rd need lots of throttle to have any kind of power. Remember it's a powershift with torque converter not direct drive like an AG tractor. I usually downshift to 1st when digging unless it's loose topsoil or something. I've got some rubber to keep lines form rubbing together too. It looks like only 2 bolts could be used for the new bracket? Even on flat ground if you drive in 2nd at full speed it should coast a bit if you pop into neutral. Glad it's working.

 

[AllDodge]

It could be I'm not giving it enough throttle, will need to work with it some more, thanks for the help

 

[Old Magnet]

Just for curiosity here's how those later valves are plumbed in later applications...