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Discussion Starter · #1 · (Edited)
I have a set of 9mm injectors from an original 4BT head but it had cracked so I bought a PROMAXX which I believe are 7mm heads. Can the tips on the injector be changed to a smaller size or is it easier to replace the whole injector?

Injector info: Kdal 50 59p2 649 246bar
Bosch (937) France
Tip # 8446

What brand would be a cost-efficient but quality option for a VE Pump With Denny T pin and 3200 Gov spring? Not shooting for big power, only enough to get out of its own way but still MPG as its main focus. Thanks
 

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Probably yes to both questions. Tips can be changed which will involve the tip assembly and tip holder. Cost to do that may be as much as replacement 7mm units. To do it will also require access to those darn expensive little shims to set the pop pressure. Might contact member NascarMark and see what he says. I know Cummins no longer sells the 9mm injectors for the early type head. Stock injectors for a VE pump engine were 4x.012 unit in the road engines. Those are usually good for a bit over 200 HP and are usually good for what a single turbo can do. The next step up would be the 5x.012 which can put you into the 300 HP area and would need twin turbos.
 

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Discussion Starter · #3 ·
Probably yes to both questions. Tips can be changed which will involve the tip assembly and tip holder. Cost to do that may be as much as replacement 7mm units. To do it will also require access to those darn expensive little shims to set the pop pressure. Might contact member NascarMark and see what he says. I know Cummins no longer sells the 9mm injectors for the early type head. Stock injectors for a VE pump engine were 4x.012 unit in the road engines. Those are usually good for a bit over 200 HP and are usually good for what a single turbo can do. The next step up would be the 5x.012 which can put you into the 300 HP area and would need twin turbos.
What's a fair asking price for the original injectors? The guy that rebuilt my VE pumps did my injectors too so I guess I'm stuck with a set of rebuilt injectors that I cant use.
 

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Do you have the serial number of your engine? I could look on Quick Serve and find the replacement part # which would be 7mm. I looked up the injector for a VE pump engine CPL 0767 and the new 7mm replacement is Cummins part 3802316. Those come with the 7mm to 9mm adapter sleeve which you wouldn't need but that's how they are packaged. Those are new ones and retail is $214.79 each. OUCH. Oregon Fuel Injection sells those rebuilt for $78 + $40 core. Not sure if your 9mm cores would be accepted or not. That's about half the price of new ones from Cummins. You'd want to verify that's what you need. Here's a link to their site. INJECTOR 7MM CUMMINS 3802316 Now that you have a Cummins part # you could check around.
 

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You cannot simply just change the nozzle and nozzle holder, other internal parts associated with the nozzle is different for a 9 mm versus a 7 mm
 
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Mark, I sort of wondered about that. I guess the new replacement injectors that Cummins shows were engineered with the correct threads for the fuel lines and 7mm tips. The part 3802316 is what they show as the current replacement with 7mm tips. Not totally positive, but seems I read those are actually 5x.012 tips instead of 4x.012 that was on the old 9mm. Not sure if that was true.
 

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Yes because it’s still an actual 9 mm nozzle so all the parts match up correctly. Specially the interior sealing ring.
 

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Discussion Starter · #9 · (Edited)
Do you have the serial number of your engine? I could look on Quick Serve and find the replacement part # which would be 7mm. I looked up the injector for a VE pump engine CPL 0767 and the new 7mm replacement is Cummins part 3802316. Those come with the 7mm to 9mm adapter sleeve which you wouldn't need but that's how they are packaged. Those are new ones and retail is $214.79 each. OUCH. Oregon Fuel Injection sells those rebuilt for $78 + $40 core. Not sure if your 9mm cores would be accepted or not. That's about half the price of new ones from Cummins. You'd want to verify that's what you need. Here's a link to their site. INJECTOR 7MM CUMMINS 3802316 Now that you have a Cummins part # you could check around.
It's 858, been doing metalwork all week while the cab is off so I can get it jambed out before cold weather hits. Diesel tuff has 4 for $420.00 no core plus the turbo available I will be running. I was hoping to get the injectors fixed without buying all new ones but it sounds like it might be just as cheap to buy them. I don't fancy the idea of core-ing the old ones out as they have just been gone through when my injection pump was rebuilt.
 

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There are some cheaper solutions on injectors but they will be no name brand items. You can get them for around $40 each including shipping from China. One of the current numbers is part 3802325. Oregon Fuel Injection charges $92 to rebuild your 9mm core to a 7mm tip which is very much in line with Mark's price. So his price is very fair. Most people don't understand that rebuilding an injector involves more than just bolting on a new tip. Unless you source imported parts, the genuine parts only come from Bosch and they don't sell to individuals. Have to go through a Bosch dealer. You also have to have equipment to set the proper pop pressure and a selection of those darn expensive shims. Those little devils cost like $6 each and there are 32 different sizes. A rebuilder could have thousands of dollars in just those because you never know which one you'll need to get that pop pressure just right.
 

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Discussion Starter · #12 · (Edited)
There are some cheaper solutions on injectors but they will be no name brand items. You can get them for around $40 each including shipping from China. One of the current numbers is part 3802325. Oregon Fuel Injection charges $92 to rebuild your 9mm core to a 7mm tip which is very much in line with Mark's price. So his price is very fair. Most people don't understand that rebuilding an injector involves more than just bolting on a new tip. Unless you source imported parts, the genuine parts only come from Bosch and they don't sell to individuals. Have to go through a Bosch dealer. You also have to have equipment to set the proper pop pressure and a selection of those darn expensive shims. Those little devils cost like $6 each and there are 32 different sizes. A rebuilder could have thousands of dollars in just those because you never know which one you'll need to get that pop pressure just right.
I sent them an email last night so I'm waiting on a reply. I prefer to have all bosch parts rather than aftermarket options.

Update: Oregon said it would be the same as just buying them plus my cores and $20.00 charge each core because it's going from a 9 to a 7.
 
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