Bought this 78A today.  Been sitting a few years, but it started right up.  Water pump will need attention. Previous owner says the master clutch is pushing oil into the engine.  I’m hoping a plugged clutch compartment breather is causing that, but time will tell.  

BP. 

That would make a good ag Cat.

Yes it would. I’m sure it was at one time.  I can see signs that it had a cab.  

BP.  

Bruce wrote:

Yes it would. I’m sure it was at one time.  I can see signs that it had a cab.  

BP.  

***It looks like Bruce likes them TOPLESS! Come on, your kids are getting too big to use the cabs as playhouses and bus stops, what became of it? I see the famous notches burned out of the nose for air conditioner compressor? No wonder you said space was becoming scarce...
Is the turbo on that one factory for altitude or more kitties? We will surely get to see shiny track pads if it snows there. Videos of you plowing the ski road? You cannot let the D6 have all of the glory! 
Another nice score for BP. Love it! JM
 

Usually oil transfer is from engine to clutch compartment threw rear engine crankshaft seal if both oil levels are correct

rjh-md wrote:

Usually oil transfer is from engine to clutch compartment threw rear engine crankshaft seal if both oil levels are correct


Thats the way I usually figured it.  Owner said he was driving fence posts with the blade and slipping the clutch quite a bit. I figured the oil in the clutch compartment got pretty hot, and if the clutch breather was plugged, it might start to push oil into the engine.  I’ll check that breather first.   

BP. 

JM, I think this is a factory turbo. It’s got the plate on the dash that says it’s good for 7500 ft.

BP.

Hi, Bruce P.
NICE catch. Thanks for sharing.

As I understand it, Cat originally started fitting turbos to 'normalize' machines for working up to a set height above sea level, hence the altitude setting noted on the plate. At some point, they changed from that approach to using turbos to gain extra HP from a given engine or the same HP with a reduction in fuel consumption. I don't know when this switch of approach started happening but I would guess at somewhere in the early-mid 1960s. At that time, it appears that they stopped putting the altitude rating plates on their machines.

But you probably know much if not all of this anyway.

Just my 0.02.

Lots of changes to the 78A. What s/n is it?
 

Thanks Deas. I figured that was how the turbo was used by Cat in the beginning. It would be interesting to know when Cat considered the turbo as a performance enhancer. I’ve noticed sometimes the parts book calls them a normalizer, sometimes a turbocharger.

Old magnet, in all the excitement about getting it running, I forgot too look at the sn tag. I’ll check it out when I get it home. Thank you for the list of improvements.