1973 Case 450B - 207 Runs and Dies

MaPaHa

New User
We are having trouble with our Case '73 450B dozer. This dozer sat for 15 years or better and we've gone through various parts of it to get it back in operation. Head gasket, various fluid leaks, general maintenance including the fuel system etc. We've used it several days but now for two days in a row, it will run for several hours with no problems and then die. It will restart with no problem and run for 5-20 seconds and die again.

We have good natural flow from the fuel tank through both filters all the way to the injector pump. We've blown air back into the tank on both the supply and return fuel lines and they seem to be clear and we've changed the filters two times now. I read on another post here to loosen the timing cover plate and when we do that and allow a decent amount of fuel to leak, it runs and works ok. There's another plug on the side of the pump that we can loosen and it does the same thing and runs. While it's running we took the return line lose and there's nothing coming from the injectors and it's only trickling out of the injector pump.
We've loosened each injector line at the pump to check for air but they appear to be spraying fuel only.

Is it possible that there's an air-lock still in the pump and or injector lines, or does this sound like something within the pump itself?

Thanks for any help,
Mark
 

If it runs ok with the timing cover loose and fuel leaking out you need to be contacting one of the pump guys that post on here or your local pump repair shop. That is a sign your pump has internal problems.
 
What Jim said.. Loosen the two screw timing cover on the pump side, if engine runs OK WITH the fuel leak but dies/acts up with cover tight, it's confirmed, time for injection pump repair. I repair/test/return two or three a week for the same trouble.
 
It is likely a piece of plastic fell apart inside the pump. It is a common issue in the Stanadyne DB rotary-distributor pumps. I had a 188
diesel in my Case 580CK and the ring went. I put a new one it. A few years later, I upgraded to a 207D and the plastic fell apart in that
pump also. Less then $50 in parts to fix IF you know someone willing to fix it (without charging for a total pump refresh).

Note if the machine is a long-term keeper, you can eliminate that plastic ring forever - for an extra $50.
 
Thanks a bunch for the input. Again, today it ran great for 2-3 hours pushing dirt and then started acting up. We broke it down
and got the pump taken off. That's good to know about the year model and will help in finding parts. We won't use this dozer
heavily so maybe after we get a few more things fixed it will make a good machine to have around the home place. Still have
several projects lined up for it.

Thanks again, I'll post back when we get it going,
Mark
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top