kraigthomas wrote:I have a 1968 JD450, in a previous "am I crazy" thread it seemed unanimous that my injectors need some help. I don't want anyone upset with anyone else, but I'm new enough to all of this to need to ask for further advise.
1) Are the injectors rebuildable or buy them new is the only option? If they are a new item only does anyone know of an internet site where this kind of stuff can be purchased?
I already gave my answer once, so maybe I'm wasting my time doing it again. You'll have to do your own reseach and draw your own conclusions.
One more time, no - they are not rebuildable. They have moving metal parts and those parts wear over time. There is no cost-effective way to renew those parts unlike bigger injectors that use replaceable nozzle-tips.
Pencil-injectors that all 350s and 450s use are bascially "throw-away" units. That being said - these pencil injectors are orifice-hole type units, and NOT pintle-type. The difference is - they have many very small nozzle holes to atomize fuel. So, there are some injectors that malfunction because the holes plug - before they are mechanically worn out. I used to work in a diesel pump/injector shop. During slow-times, we'd pull used pencil injectors out of box (that we got for free), and test one by one. Any that we found that were only half worn-out with plugged holes - we'd unplug, clean up, and sell as "rebuilt." Maybe 1 out of 5 was worth using again. When you buy a "rebuilt" pencil injector, you are getting a somewhat worn but cleaned up injector - and that is all.
Considering how difficult they can sometimes be to get out, it's not something I'd use. I just put new pencil injectors in my Case and they cost me $65 each. I hated to do it, but that's just the way things are. I just put brand new injector nozzles in my Ford truck and they cost me $6 each - brand new. That's what's nice about big injectors with replaceble tips.
In regard to using a chemical injector cleaner? In my opinion, it is a total waste of money. When these pencil injectors get plugged orifices, the plugs are rock hard and often even a special cleaning wire won't work. There are some very pricey ultrasonic cleaners that will sometimes break the clogs loose. A chemical cleaner, in this situation, is a joke.
In regard to buying? I've tried buying aftermarket, direct from Stanadyne, and from Deere or Case. In just about every situation, it was just as cheap to buy OEM from Deere or Case, as it was to buy somewhere else. Maybe there are some deals out there, but unless it's left over surplus, I haven't found them. Stanadyne has the patent rights on the pencil injector, and I've yet to see any made aftermarket. But . . . even many of the OEM injectors are now made in China, so ther may be some "knock-offs" out there for sale.
They are not very common. Case, Cat and Deere use them in some applications. So did GM in some early Oldsmobile V-8 diesels. Maybe a few Olivers.
Deere 450 can use any of the following. I'm giving the Deere #s along with the Stanadyne/Roosamaster #s:
AT18064 (Roosamaster 16422, 17511, 17427). Has four .012" orifices.
PSI - 2750-2850 new and 2550-2650 PSI used.
AT25502 (Roosamaster 17579,17574). Has five .010" orifices. 2950-3050 PSI new and 2750-2850 PSI used.
AT30299 (Roosamaster 18457 and 18458). Has five .010" orifices. 2950-3020 PSI new nad 2750 to 2850 PSI used.
AR49876 (Roosamaster 18742, 18717, 20492, 20491). Has five .010" orifices. 3150-3250 PSI new and 2950-3050 used.
AR49877 (Roosamaster 18742, 18717, 20492, 20491). Has five .010" orifices. 3150-3250 PSI new and 2950-3050 used.
AR56289 (Roosamaster 19762). Four .011" orifices. 3150-3250 PSI new and 2990-3050 PSI used.
AR56290 ((Roosmaster 19763). Four .011" orifices. 3150-3250 PSI new and 2990-3050 PSI used.