Hello IATN folks,

I have a small fleet of Ford 445 industrial tractors I maintain for a local Farm and Feed supply company. At one time or another there have been issue with the injector pumps leaking. Usually, I would properly time the engine and injector pump marks, then pull them and have the owner send them in to an area diesel shop for rebuild. A problem came up recently when the rebuild shop would quote a base price and once, they had the pump, the price would double. (A sign of the times we are in)

This was confounding because the injection pump(s) would have no issue other than leaking. For this most recent one, the Feed company owner refused to have them perform the services due to shady price changes. The injection pump came back in a bag, in pieces, dirty and scatted like a jigsaw puzzle. It was obvious the rebuilder did this on purpose because they went to the effort of removing the small alignment pin that is pressed into the transfer pump cover. There is no reason to remove this pin.

What happened next was the Feed company owner said he had another Ford 445 tractor with a leaking injection pump. He asked me if I was willing to use one for example to reseal and reassemble the other scattered one. I have rebuilt and reconditioned many components in the past, so why should this be too difficult? I agreed and went to work.

The most important step in this adventure was thoroughly cleaning and laying all of the parts out in an intentional manner because these pumps rely on exact rotational orientation. These particular pumps rotate clockwise as installed on the engine, looking at the tail end (transfer pump end) of the injection pump. The weight basket, plunger ring and transfer pump all have to be clocked correctly or the pump will not work properly, or not at all. It also helps to have a sharp scribe handy to mark exact part locations during disassembly.

Luckily the pump rebuilder did not take away or add any parts and all of them could be accounted for. There was no scoring or wear on any of the parts, so it was concerning why they doubled the price. It took a few hours, but it went pretty smoothly. I reassembled both injection pumps, painted and reinstalled them. They worked great and I was relieved, and I learned a new skill.

This past week, I even tackled the Stanadyne Roosa Master JDB injection pump on my own JD 310 backhoe because it was bleeding off fuel into the engine oil and diluting it. (That's how I purchased the tractor) This was a bit of a different pump design because the pump input drive shaft stays in the engine and umbrella seals are used on the input drive shaft that take careful installation. This was not too bad of a job once I watched a few You Tube videos and understood the design. The injection pump was recently reconditioned but it was installed wrong which tore an umbrella seal.

The biggest advantage the injection shop rebuilders have is the ability to calibrate the injection pump on a test stand if parts need to be changed internally, but if it is a matter of resealing, no adjustments are ever messed with. Logically, if it came off running well, there should be no reason it will not run well once a reseal job is performed. As for torqued specs, I found the generic torque tables in many repair manuals matches the same as the factory Stanadyne pump manual torque specs.

In closing, I will point out that all of the pumps I have resealed thus far were run with good clean fuel and fuel filters frequently changed, so they were very clean with no wear issues. I do not recommend anyone attempt this procedure for an injection pump that is gummy and dirty inside or has internal damage. These poorly maintained or damaged injection pumps will require a good rebuilder with the resources to get internal parts as needed.

Bonus information: Do not run Bio Diesel in any mechanical injection pump equipment. That stuff gums up terribly and creates high wear issues, the injection pump will fail.

Glenn A. Hunt
Consultant/Owner
Automotive Doc's
Devine, Texas, USA