Anyone Know Anything About Vintage Cat D7 Dozers? Trying to Rescue a Non-Running One...

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
The plungers are what go into the little c peices attached to the lifters and up into the barrels. The barrels attach to the injection lines. They should move up and down pretty freely, but are spring loaded down to keep in contact with the cam. So some effort will be needed. You should be able to reach into the govenor and find the fly weights and get the rack to move, all 4 plungers should rotate.

Thanks for the details.
 
My uncle had a 1950 D-7 3t pony start dozer and back in mid 50's he always let me push out hedge with it when I was 10 years old. Nowdays both of us would have been in jail for doing that! LOL! Good 25 ton cable dozer at the time. He rebuilt the motor himself and put new undercarriage on it a couple times he owned it so when it sold it was top shape. If yours is that bad,--- JUNK it! Cost a fortune to fix that puppy!

There's actually a 1952 D7 3T not far from here for sale, but it's been converted to electric motor and has a cracked block.

Thanks
 
Have to keep inspiring you to complete your project Bulletpruf!
My inspiration came from a science fiction story written by Theodore Sturgeon called Killdozer. My father gave me the book in the 1960s and it featured a D7 which was called Daisy Etta after the Mexican driver calling it “De Siete”
So that is what mine is called
Unfortunately the rather poor movie starred a D 9 so lost the name!
 
Have to keep inspiring you to complete your project Bulletpruf!
My inspiration came from a science fiction story written by Theodore Sturgeon called Killdozer. My father gave me the book in the 1960s and it featured a D7 which was called Daisy Etta after the Mexican driver calling it “De Siete”
So that is what mine is called
Unfortunately the rather poor movie starred a D 9 so lost the name!


I'm hoping this old girl doesn't end up killing anyone!
 
Have to keep inspiring you to complete your project Bulletpruf!
My inspiration came from a science fiction story written by Theodore Sturgeon called Killdozer. My father gave me the book in the 1960s and it featured a D7 which was called Daisy Etta after the Mexican driver calling it “De Siete”
So that is what mine is called
Unfortunately the rather poor movie starred a D 9 so lost the name!

I remember watching that movie on KGAN Channel 2 after the 10:30PM news. That brings back memories. Now with the internet I might have to watch it again.
 
Diesel trick is to get clean, water-free fuel into cylinders and spin it fast with a good set of batteries? = Fuel filter, and good batteries b4 trying? Good Luck.

Yep. Headed back in a few days. Will work on getting winch and clutch disengaged so it can spin over faster. Will also drain the old fuel out of the fuel filter housings and replace with fresh fuel.

Owner is supposed to be charging the pair of 8D batteries for us, too.

Thanks
 
So, I'm thinking about buying a non-running D7D 17A project; should be about 1959 vintge. It's complete, said to have been running (but not running well) about 10 years ago. Owner thinks it's was having fuel issues.

It has a hydraulic blade, electric start, Hyster D7D winch. Engine is a 4 cylinder turbo, but based on the block casting, it appears to be a later D7E engine.

This would be my first piece of heavy equipment. I've been wrenching on muscle cars and trucks on and off for decades. Also have some diesel experience - Ford 7.3 IDI and PS and a pair of Detroit diesels in a boat decades ago. Now that I'm retired from the Army, I have more time to take on something challenging like this. FYI - I certainly realize that it would make more sense to buy something in better condition, but I'm not necessarily after the smartest course of action.

Anyway, back to the D7. I haven't seen it in person yet; it's 1.5 hours away from me. Going tomorrow to check it out in person. Before I buy it, I'd like to get it running, if at all possible.

Owner said he has an old set of batteries from a D4; believe the D7 should be 24V.

And this is where I could use some help. I'm familiar with the process of starting a car or truck that hasn't been running in years, but a 64 year old D7 is another situation altogether. Anyone want to take a stab at the process you'd use and the tools you'd bring?

I do have a pushbutton starter switch that will hook to the starter solenoid with alligator clips. I should be able to figure out which terminal is the S terminal on the solenoid. I'll bring ether, but I'm not a big fan of the stuff. What about getting fuel to the injectors? If I bring a 5 gallon can of diesel, can I use an electric fuel pump to get the diesel to the injectors somehow? I suspect the rack is likely stuck, so I'll check this first.

View attachment 1136666View attachment 1136667View attachment 1136668View attachment 1136669View attachment 1136670
If it is converted to electric starter DO NOT place the Start Lever on Start. That was for the pony motor start... leave it on RUN .... make sure you have pumped up the fuel primer lever by the fuel filter and have good 24vdc and turn the key on that should be on the same side as the starter and alternator. below the deck in the front... if it starts to smoke out of the stack it is trying to start... pull back the throttle just a bit and try again...
 
If it is converted to electric starter DO NOT place the Start Lever on Start. That was for the pony motor start... leave it on RUN .... make sure you have pumped up the fuel primer lever by the fuel filter and have good 24vdc and turn the key on that should be on the same side as the starter and alternator. below the deck in the front... if it starts to smoke out of the stack it is trying to start... pull back the throttle just a bit and try again...

Ok it was converted to electric start at some point, so it has the compression release. However, it doesn't turn over very well with the lever on RUN, and I was using a pair of 8D batteries wired up for 24V. The batteries were at 12.5V each so it should have had enough juice to turn over well.

One reason I think it's turning over slowly is because the clutch is dragging and the winch is engaged. The winch cables are frozen or busted, so I need to pull the small cover off the winch itself to disengage it.

I also need to check the oil level in the clutch and I also may end up pulling up the floor plates to see if the clutch brake needs to be adjusted or replaced.

Another question - does the injection pump use its own oil or does it run off the main engine oil supply?

Where would the fuel primer lever be? Pictures below.

Thanks for the input!

Scott

IMG_0462.jpg
IMG_0461.jpg
 
Today was a good freaking day!

On the road at 6:30 am. Picked up my buddy Will at 6:45 and we headed south.

Arrived at 8:40 am. Got unloaded and got to work.

Hit the bolts on the monster winch access cover with some 50/50. They came off with ease. Immediately inside was where the two cables entered the winch housing, one for brake, one for engage/disengage. Will managed to free up the brake lever with some 50/50 and elbow grease. We couldn't get the engage/disengage cable to free up, so we cut the cable at the winch with a death wheel and unthreaded the stub from the actuating lever inside the winch. Once that was done, we freed up the lever with equal applications of 50/50, brute force, and curse words. Once we had the engine turning over later in the day, we figured out which position was neutral and left it there so the winch wouldn't spin when the engine was turning over.

IMG_0534.jpg

We worked on the clutch brake next. Yes, the clutch brake; it has a wet clutch (submerged in oil) and there's a brake shoe that rides on the clutch to keep the clutch from turning when the clutch is disengaged. The clutch brake is actuated by the main clutch lever moving all the way forward. Checked the oil level in the clutch and it was good; oil was clean, too. Anyway, we figured out that the clutch brake was not actuating as it should have been when I tried to start the tractor last time, but I managed to get it in place to where it would actuate if the brake itself wasn't junk...more on this later.

IMG_0538.jpg

Next we worked on the fuel system. I removed the cover to the rack and hosed everything down with 50/50. Then, with Will watching the rack, I spun the tractor over using the HF 24v jump pack. Will reported that all the spring loaded plungers were moving up and down except for one, which was stuck in the up position. So I managed to gently persuade it to move back down to where it was in contact with the cam...and then spun the engine over again...and it stuck up again... We went back and forth for about 10 iterations of application of 50/50 and gentle persuasion and finally the plunger moved up and down its own.

IMG_0464.jpg

At that point, we weren't trying to start the engine, and we weren't building oil pressure, but I did see a slight puff of smoke from the exhaust, so then I cracked open the fuel lines at the injectors about 1/2 turn. Spun it over some more and got a fair amount of fuel flowing from each fuel line, so I snugged them down and decided to see if she would crank.

Now that it had been spinning over for a while, the jump pack was getting a bit tired, so we went up to the owner's house and picked up the pair of 8D batteries. Wired them up for 24V and gave her the beans. I didn't get much of anything with the decompression lever in the START position, but when I switched it to the RUN position, I started getting some smoke out the exhaust, so I gave her a little whiff of ether. Engine picked up and started to catch like it was going to start. This happened a few times and then she lit for good! It was running fairly rough at first, but that's because I didn't have the decompression lever all the way shut. Once I shut it, she cleaned up and idled nicely! Great oil pressure, too!

From there, I tried to get her to move by putting the forward/reverse lever in either forward or reverse, but no such luck; all it would do is grind and I wasn't about to force it. Even with the clutch lever in the disengage position and the clutch brake on, the clutch still seemed to be dragging. I could see the driveshaft spinning, too, so I suspect the clutch brake is smoked.

At that point, we were out of time and had to head north back to San Antonio.

On the way back I spoke with a guy who owns a D7 of similar vintage (D7E) and he said he has had a similar clutch brake problem with his, and he will just crank the engine over with the tractor in forward and low gear. That will either actually start the dozer in gear or it will break the clutch free so it's no longer dragging.

On the way home I also spoke with the D7D owner (he's out of town for work) and he's tickled pink that the old girl is running again.

Plan is to head back out there again in the next week or so to drain the water out of the transmission (we didn't have the correct tool to remove the drain plug) and see if we can actually get it to move.

FYI - I love to complain about south Texas summers, but days like today do NOT suck - sunny and highs in the low 70's. I was in short sleeves at the end of the day.

I'll work on editing the video over the next few days and will post to my YT channel.
 

Latest posts

Back
Top