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Cat 931 help.

Joined
Jan 2, 2024
Messages
1
Location
Lowell , In
I’m interested in this old b*****d. I do land clearing and think it would be nice. Guy says dad owned it 20-30 years . Dad put a trans in 5 years ago and since passed away. Ran when parked. Right pedal stuck. Said they recently had it running but fried the starter getting it going. Said leaks coolant and hyd hoses are leaking. From what info I found 3204di cat. 931b. What’s it worth given the info and you think I could pull start it or no ?

Also will it freely move if I have a machine to push it onto a lowboy ?
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OzDozer

Senior Member
Joined
Jan 18, 2007
Messages
2,207
Location
Perth, Western Australia.
Occupation
Semi-Retired ..
It's a late 1979 model 931B. They were available in 3F/1R transmission or 3F/3R transmission. I think the 29Y series is 3F/3R?

No, you can't pull start it, because it's fitted with a powershift transmission that requires oil pressure to engage gears, and that requires the engine to be running.

Right pedal stuck is common, it could be rusty linkages, or it could be brakes rusted on. They have a tendency to rust on, and that will make pushing it onto a low bed a whole lot more work.

Find out where the coolant leaks are coming from first. The likely places are the water pump seal, or there's a big rubber seal between the top of the rear of the front cover and the front of the cylinder head.
This seal only seals because it's compressed with two hose clamps, which forces the seal against the sealing faces on the front cover and on the cylinder head.

There are also two small diameter (5/8" - heater hose size) hoses between the oil cooler and the engine, and between the oil cooler and the cooling system. These may be rotted out. The oil cooler is located at the lower right front of the engine block, under the fuel injection pump.

Also, the hose fittings into the block and the cooling system for these oil cooler hoses are steel, and may be corroded out.

Frying the starter motor whilst trying to start it doesn't sound good. Was the starter motor in poor condition, or did it get fried by cranking with low batteries and excessive amperage?
Or by cranking it for too long and cooking the starter? You have to be very careful with keeping cranking time short, and allow plenty of starter cooling time.
It's also better to ensure the engine has everything it needs to start easily, rather than just cranking it continuously.

These machines require a specific, dedicated 931B starter that has the solenoid located in a specific location, because they are a very tight fit. The starter part number is 3E1865. They're a heavy starter - 22kgs or 50lbs.

You'll have some real fun getting at the starter bolts - you get at the top and side ones from the top front, and the bottom bolt from below after you've removed the transmission belly guard.
You may need to "reshape" some wrenches with the gas torch, for the job!

I'd have to opine its worth $8K if it runs O.K. If the engine is in poor shape, then you need to factor in an engine overhaul, and it will be worth a whole lot less.
 
Last edited:

Welder Dave

Senior Member
Joined
Oct 11, 2014
Messages
12,554
Location
Canada
29Y is 3F/3R. Can't see what shape the undercarriage is in. Hard to put a value on it but OzDozer is probably as close as one could get. It might need a lot of work.
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
29,423
Location
G..G..G..Granville.........!! Fetch your cloth.
Guess what. You are/were not the only person on this forum that is/was looking at it. I thought those photos you posted looked familiar.........

 

Welder Dave

Senior Member
Joined
Oct 11, 2014
Messages
12,554
Location
Canada
I noticed the pic. with the 3 batteries looked familiar but didn't realize this was from a different poster. Personally that machine looks pretty rough and I think could take a lot of $$$$ to get it working properly. I've done a lot of work on my 931B so know how much things can cost even on a smaller machine.
 
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