Hi Have a 1967 or 68 I think D5 (84H) that ran awesome until one day it started falling on its face at anything over idle, even in neutral with no load.  Let it cool down and runs good until fully warmed up.  Then it stumbles and smokes white/grey smoke profusely.  Its like a switch flips when it reaches full operating temp.  Could it be a injection pump issue?  Just odd how it can start great and run fine for the first 10 mins of operation.   

Things I've looked at already:
Air filters new and clean
Fuel filter new and clean
No bubbles or pressure in radiator
Coolant temp normal when fully warmed (took rad cap off slowly with no pressure or boiling)
Cleaned out sediment bowl, no screen in there and can't find one that fits.  Parts book PN   
Lift pump spring swapped out for a stiffer one, gage now pegged but no difference.
Injectors removed and looked at by a shop- reportedly all spray well.  The guy said there isn't a pressure they open up at, they are literally just a nozzle? 

Some people i've talked to are questioning the pump but it seems odd how it runs so well for the first 10 mins or so.  Is there someone in MN that rebuilds these old pumps or works on these old Cats? 
 

Two things that you did not mention. Is the vent on fuel tank clean. Are there any hoses used in the fuel system that could be collapsing.

I have had a similar situation with a Detroit Diesel. Ran cold then lost power to run well after fully warmed up. A bit different fuel system, but a new pump made it better. The DD pump was cheap, so a no brainer to change. This Cat pump will be vastly more I sure don't want to tell you it will fix things. My guess is the warn DD pump had parts that warmed up at different amounts of time.

To start with the injection capsules do have a breaking pressure, a rather wide range of 300 to 800 psi with replacement required if they can't make 300 psi.
The filter element is a 9M5451.
What are you getting for fuel pressure? Using a real gauge.

Ray54 wrote:

 Is the vent on fuel tank clean. Are there any hoses used in the fuel system that could be collapsing.

I have had a similar situation with a Detroit Diesel. Ran cold then lost power to run well after fully warmed up. A bit different fuel system, but a new pump made it better. The DD pump was cheap, so a no brainer to change. This Cat pump will be vastly more I sure don't want to tell you it will fix things. My guess is the warn DD pump had parts that warmed up at different amounts of time.

 

Vent is clean and its all solid metal fuel lines.  

I suppose there could be a pump clearance that is opening up.....   how hard are these pumps to rebuild?
 

Old wrote:

To start with the injection capsules do have a breaking pressure, a rather wide range of 300 to 800 psi with replacement required if they can't make 300 psi.
The filter element is a 9M5451.

What are you getting for fuel pressure? Using a real gauge.

 

Scratching my head on the break pressure, I too thought it was odd they wouldn't have so either the either the shop didnt actually test when they said they did or they just tested the bodies?  I just scrounged up a old Bosch injector tester (bosch 0681200502) and hooked one up and it looks like it wants to build pressure in the nozzle itself.  It also looks like i need a fixture or to pull a prechamber to hold the nozzle against the body tight enough to hold pressure to actually test?  Pulling the prechambers is a bit more involved than I was hoping.   

As for what fuel pressure am I getting, do you mean between lift pump and injection pump or coming out of injection pump when machine is running with injectors installed?  

As for the filter element, thats the PN in my parts book but Cat is showing no results for that PN and i can't find online anywhere.  Does it have a threaded stem that screw in to a blind hole above or just held in by bowl bottom?  

I was referring to lift pump pressure check.
The proper test apparatus has a holder for checking capsule pressure.
Check here for filter element...www.machinerytrader.com/parts/search?Par...451&SearchType=Start
Injection pump is not hard to overhaul but I doubt that's your problem. Those early scroll pumps go forever unless you get water in the fuel.

have you check the breather vent on the fuel cap ?

if the injectors were sad would that be a issue from start up?

unless there losing spring pressure due to heat. but that would be really weird.

as for that filter screen try adding a zero after the m sometimes that works in the cat parts lookup system. or give the nearest dealer a call they may have to look under classic parts. also a google search is your friend.

also try this part number CA9M5451

trainzkid88 wrote:

if the injectors were sad would that be a issue from start up?

unless there losing spring pressure due to heat. but that would be really weird.

as for that filter screen try adding a zero after the m sometimes that works in the cat parts lookup system. or give the nearest dealer a call they may have to look under classic parts. also a google search is your friend.
 

I would think so, but running out of other possibilities.  

Not a bad idea to call the dealer and see if theres a guy there thats helpful with the classic parts.  I really wish I had the old element screen to compare to. 
I've googled it several times and still come up empty on the filter.  This definitely isnt the first place I've asked.