What's so special about the injector pump nut/washer? Replacement?
 

I saw in a post on here somewhere about a replacement injector pump nut, I can't find the thread now though. It was a deeper nut...anyone know what I'm talking about or where to find it?

Also, my washer is flat, I need a replacement. What kind of metal does it have to be? I called the dealer, they want $21 for the nut, $5 for the washer! If I know what kind of steel/metal I need I can probably get one from the local bolt manufacturing joint here instead, unless there is something special about them? Plus it won't be in until next week.

Thanks...

The washer is slightly concave so that it acts like a lock washer.
Not real sure you'll be able to find one easily elsewhere.

I've aways reused the old nut.

When I did my timing I changed both my nut and washer, although I could have reused the nut. Got them from Cummins, here are the part numbers:

Nut: Cummins 3920921
Washer: Cummins 3920922

I think the washers are just a few dollars.

I took a quick look at the washer, it looked like an actual lock washer, unless I'm mistaken...?

So it's not just a regular lock-washer then eh...bummer. I have a couple Cummins places around I'll see if they have or can get them.

Thanks for the part #'s!!!

This was originaly posted by "BERNER" on another thread.


Here's a photo of the nut upgrade. It's from Saskatoon Diesel Services Their part # is AT90. Price in 2002 was $14.29.

their web site.
 

OK that's what I remember reading, I couldn't find the nut anywhere on the site before though. I guess I should just call up there and ask for it. Nobody's tried since '02?

Do you replace the washer each time?

Here's a photo of the nut. https://www.dieseltruckresource.com/...2P7100Nut2.JPG
Saskatoon Diesel told me that no washer is req'd with this nut. I think they torqued it to 180 ft-lbs. It was a while ago.

They'll be able to tell you what to torque it to if you call them.

Thanks for the pic...sure doesn't look like a washer would fit with that nut.

I called up a local Cummins dealer, part should be here tomorrow, $11.83 for the nut, $2.90 for the washer. Another dealer was similarly priced. I should probably order that big nut and have it on hand to replace some day though...but for now I just wanna get this hooptie running again.

I'm sure there are those that don't, and never have any problems, but if you want to minimize the chances of the timing gear slipping on the shaft, its a good idea to replace the washer, and maybe even the nut. Since adjusting the timing is not a job I'm interested in doing more than once, not only did I replace the nut and washer, but I also removed the timing cover so I could take the gear off and hose it down with brake and contact cleaner. Any oil or dirt on the gear/shaft matting surface can cause the gear to slip. I know most people don't do this and never have a problem, but taking the gear cover off also gave me the chance to fix the KDP and change the leaky gaskets.