Hey guys, I just bought a late 1980s Cat D3B to use around my place. I specifically wanted a smaller machine so i could get around easier between trees and such. It seems like a good solid machine but it does need some attention. Specifically it needs the brakes adjusted or replaced as they require quite a bit if pressure to turn the machine. It also needs a bushing/pin replaced in the front of the U shaped crossmember that the 6way blade attaches to. Any info or help any of you could give me on this machine would be helpful. Also would anybody on this forum have a service manual for this old machine? I sure could use one. What fluid types does this cat use in the hydraulics, trans, bevel gears? Thanks Matt
Underneath the floor boards to the front side is the hydraulic controls for steering, cant remember exactly, but there is a little spring that needs replacing. The D3b's were notorious for that spring problem
D3B brakes I had one that i sold a couple years back. I put new brake bands on just before I sold it. The brakes on these are dry bands that wear down pretty quickly if used alot. The is an access panel at the back for replacing the bands. To adjust these, you need to remove the seat. There will be 2 small covers that each have 2 bolts in them, one for each side. Turn the adjuster nut to the right to tighten the band, I think it took a 9/16" socket. I did say its been a couple of years, so I could be mixed up with another machine. Don't hold it against me if I'm wrong. Not sure what to say about the pin in the front, except that you will probably have to torch it out. Rather than buying a new pin from CAT that would still be loose as the hole is probaly wallowed out, check with a machine shop about getting one milled to fit tight. They can drill and tap them for greese zerks too.
I have a lathe so i can make the pins and bushings, I was just wondering if the main pin i need to replace wasnt some kind of ball shape in order to let the blade pivot in all the directions it has to?
The pins are just normal round pins. There should be a horizontal pin and a vertical pin that will allow it to swivel in all directions.
On the subject of D3's, would anyone have a service manual for a D3C LGP, I think 1990 year? I don't know much about this crawler and wonder about the Hystat decal on the side. I thought hystat meant the machine would be joystick controled. Maybe someone had extra hystat decals and wanted to use them up?
Sorry to hi-jack this thread but for some reason I'm not able to start a new one. Upon closer inspection and using a bar I see that both of my sprockets are loose on my D3C. When backing up the left track will stick and stop the crawler. I'm guessing pinion is bad and probably more problems. I don't have a repair manual for this Cat but have read an older D3 manual. There it says that the steering clutch has to be removed, press off the hub and then you can remove the final. Would this apply to the D3C? I've taken finals off the old D2,D4,TD6 and 9 with no problem but this sounds like a big job, especially without the proper puller. I thought jobs like this would have been made easier:Banghead
The D3B has two steering valves located under the seat. There is a roller bearing on the end of the valve that is known for going bad. It dows not push the valve all of theway in to release hydraulic pressure on the clutches. Check this first. To adjust the brakes first disconnect the lever rod and spring going to the brake lever under the seat. There is an oval shaped cover with two screws holding it on that covers the brake band adjustment rod. There is also a bolt undder the machine that supportsthe brake band form thh bottom. Loosen it it up first. Then tighten the top adjustment up all of the way tight then back off 1 1/2 turns. Then tighten the bottom al of the way tight and back t off 1 1/2 turns then tighten the jam nut. Adjust the brake rods until you have about a half pedal of travel. I have heard that you can put brake bands on without pulling the clutches but I did not have any luck doing it. Might as well put a bearing and clutches in if you pull the pack to install brake bands. I bought the brake pads and riveted then on the bands myself to save some money.
Thanks HT your explanation sounds like exactly what i see with the floor plate removed. I will dive into it as soon as i can. Do you know what kind of trans fluid these old tractors take? Or will they run with anything in them?
From all of the information that I hav gathered you can use the same oil. I use Mobil Delvac 15-40 because I got a deal on a bunch of it last year. Some people prefer Shell Rotella. One thing to watch for on the 3204 engines is not to run them hot. The 3204 is also known for having a lot of blow by as they only have a 2 ring piston unless they have been overhauled with an upgrade piston kit. The engines do not come with liners so they have to be bored to be overhauled.
By the way here is a forum that has alot of information on the older dozers" http://www.ytmag.com/crawlers/wwwboard1.html
I use 30W motor oil in my trans/bevel gears and just regular hydraulic fluid for hydraulics. Mine is a 1987 D3B. I'll also throw out a couple questions: mine is horrible about cranking. It drags slow and starter gets hot. At times, it cranks fine but usually it's bad. I put a brand new battery in and it helped a little while. I was told some new battery cables would help.
Could be you need new brushes in that starter. Cleaning up the armature and everything else inside is a good idea while you are at it. Try do it yourself and if you can't put it together then take it to the starter shop like you would do in the first place anyway.
Oh, and on another note, I had a bad pinion gear in my D3C. Not too bad a job to replace. Cat wanted $1800 for the pinion and I found a new one for $225 and then later found out they are $100 in the USA.
D3Dave if you don't mind telling me where pinion was able to be found for 225 or 100 I would appreciate it realize this is a older post but was hoping Jeb