# Long 680 Injection Pump Problem



## goebelmj (Aug 13, 2021)

Good Day All!!

I tried to start my Long 680 after a brutal winter here in Texas and she would not start. It fired when I used a little starter fluid but would not fire on her own.

I went through the troubleshooting steps to make sure I had all the air out of the system and diesel all the way to the injectors. Well, I have no diesel coming out of the injection pump thus nothing to the injectors.

So, I have some of questions.
1) Do injection pumps really go bad and just quit pumping?
2) How hard is it to replace the pump myself?
3) Where would be the best place to purchase one online?

Also, I plan on replacing the booster pump while I'm there.

Thanks all in advance,

Mike G.


----------



## Fedup (Feb 25, 2014)

1) Yes, those pumps do "just quit pumping", but usually after periods of non use. Yours could well be a candidate for that. 
2) Hard to replace yourself? Not really. The procedure is very common, well documented in many places, and always available.
3) Replace it with a new one? Only as a last resort. New ones are mostly junk, nothing you really want to fool with if you can help it. Fix the one you have. There a number of places (literally hundreds) that rebuild pumps, some more expensive than others, but in general, that pump should run $450 - $600 depending on what if any internal parts it needs that don't come in "the kit". I wouldn't suggest "doing it yourself" no matter how many U tube videos you watch.


----------



## goebelmj (Aug 13, 2021)

Fedup said:


> 1) Yes, those pumps do "just quit pumping", but usually after periods of non use. Yours could well be a candidate for that.
> 2) Hard to replace yourself? Not really. The procedure is very common, well documented in many places, and always available.
> 3) Replace it with a new one? Only as a last resort. New ones are mostly junk, nothing you really want to fool with if you can help it. Fix the one you have. There a number of places (literally hundreds) that rebuild pumps, some more expensive than others, but in general, that pump should run $450 - $600 depending on what if any internal parts it needs that don't come in "the kit". I wouldn't suggest "doing it yourself" no matter how many U tube videos you watch.


Thanks Fedup! It appears to be easy to remove and replace. I just am not sure if there is any trick to stabbing the new one back in. It appears to be keyed, guess I'll find out when I pull the old one.

Unfortunately I am under a time constraint. We just sold our property and I need to get the tractor home within the next couple of weeks. A new one is my quickest option at this point. I'll check out YouTube...

Thanks again!


----------



## Fedup (Feb 25, 2014)

If you've never done it before, don't just dive in. There are manuals available everywhere, I (or others here) probably have one that can be shared. 

It's not complicated, but you should be aware of the steps involved, getting it lined up before removal so you aren't in trouble putting it back.


----------



## goebelmj (Aug 13, 2021)

Fedup said:


> If you've never done it before, don't just dive in. There are manuals available everywhere, I (or others here) probably have one that can be shared.
> 
> It's not complicated, but you should be aware of the steps involved, getting it lined up before removal so you aren't in trouble putting it back.


I've been looking for a repair manual online but haven't yet found one. I'm beginning to see the 680 seems to be an odd model. I would be very appreciative if someone could share the section on repairing the injection pump.

Thanks Fedup...


----------



## goebelmj (Aug 13, 2021)

Fedup said:


> If you've never done it before, don't just dive in. There are manuals available everywhere, I (or others here) probably have one that can be shared.
> 
> It's not complicated, but you should be aware of the steps involved, getting it lined up before removal so you aren't in trouble putting it back.


And I was wondering if I have to drain the oil before removing the old injection pump.


----------



## Fedup (Feb 25, 2014)

https://tractorpoint.com/pdf/Long-Service-Manual-360-460-510-series.pdf



This isn't your exact model, but so many tractors produced under the Long label are so similar in design that much of this applies to most of them. The instructions are rather basic, granted, and not very well detailed, but the sequence of procedures is explained. There are a number of tricks that one learns with experience, but much of that can be explained if needed. 

And the oil need not be drained.


----------



## goebelmj (Aug 13, 2021)

Fedup said:


> https://tractorpoint.com/pdf/Long-Service-Manual-360-460-510-series.pdf
> 
> 
> 
> ...


Awesome, thanks Fedup!! I did some research and read where a guy pulled the cover plate, marked the gear locations, pulled the old pump and installed the new one. This sounds like an easy way to replace the pump (which worries me a bit). Any feedback with this procedure would be appreciated.

Mike G.


----------



## thepumpguysc (Jan 25, 2015)

It’s rather easy.. only hard part is getting the correct puller to pop the gear loose..
U WANT TO MARK THE GEARS TO EACH OTHER.. just incase it slips..
There’s a timing line on the mounting ear of the pump.. THAT LINE lines up w either a set of degree marks or another line on the engine block..
PAY ATTENTION WHERE IT IS.!!
Take the lines and the linkages off, pop the gear and then it’s the 3 bolts holding the pump to the block.. DONE.
If u wanna send it to me, I can get it back in the mail in 2-3 days..
So your complete job won’t be but a week..and probably just a little more than 1/2 of the internet prices I’ve seen.
Good luck w everything.. TPG


----------



## SidecarFlip (Mar 25, 2021)

Noting and recording the EXACT position of the timing marks and the relationship of the gears to each other is vitally important. Had a buddy with an 806 International that pulled the pump and never recorded anything. Got a rebuilt pump and it took him about a month of fiddling around to get it to run again. he wasn't a happy camper. Asked me to help him and I respectfully declined.


----------



## thepumpguysc (Jan 25, 2015)

Lol.. I know whatcha mean flip..
It’s a nitemare when the engine manufacturer leaves enough room for the drive gears to slip past one another.!
I do this stuff in my sleep AND STILL mark gear positions.. cuz u just never know..
Even if I can’t mark a gear to a gear, I’ll mark something to the timing cover.. a key way or a bolt hole.. something..
This may sound silly after 30+ years of doing this but.. you’ll never see me doing the same job TWICE.!! Lol


----------



## goebelmj (Aug 13, 2021)

Whew!! I'm feeling a lot better about tackling this project with the help of you guys. This has certainly been a learning experience. The trouble with the diesel tractors I have owned is they just keep on running year after year without a hitch. When they break, at least for a diesel rookie like me, it turns into a huge research project.

Thanks a ton fellas, you have been a huge help!! I'll update this post when I get her running again.

Mike G.


----------



## goebelmj (Aug 13, 2021)

thepumpguysc said:


> It’s rather easy.. only hard part is getting the correct puller to pop the gear loose..
> U WANT TO MARK THE GEARS TO EACH OTHER.. just incase it slips..
> There’s a timing line on the mounting ear of the pump.. THAT LINE lines up w either a set of degree marks or another line on the engine block..
> PAY ATTENTION WHERE IT IS.!!
> ...


thepumpguysc, just messaged you...


----------



## goebelmj (Aug 13, 2021)

And one more question related to the fuel system. Is there anything I should be aware of when replacing the lift pump? 

Mike G.


----------



## goebelmj (Aug 13, 2021)

So far so good. Pulled the cover plate and marked the gears. I didn't find any reference (timing) mark on any pump ear to the mounting body so I peened a mark across a pump ear and the mounting surface. Took pictures of all the marks and mounting location of the pump. Disconnected all the attached lines and rods. Loosened the cap screw on the gear, removed the three mounting bolts from the pump. Backed the cap screw out and the pump dislodged from the gear. It appears the cap screw acts as a "puller" when backing out. 

Boxed and sent to TPG.

Thanks for all the help guys, much appreciated.

Mike G.


----------



## goebelmj (Aug 13, 2021)

Got my injection pump back from TPG is short order. Thanks for the quick turnaround Mike!!

Replaced both fuel filters and the lift pump. Cracked the injector lines at the injectors. Installed the reworked injection pump and lined up the timing reference marks. Double checked the the reference marks I placed on the pump gear and tighened it up. Bled the air out of the system and turned the motor over. Got fuel at the injector inlet lines, tighened the injector lines and turned the motor over again. She cranked and ran a few seconds then died. Bled the injection pump again and still had a little air in the pump. Cracked the injector inlet lines and turned the motor over again. Got fuel at the injector inlet lines again and tighened them up. Turned the motor over for about 10 seconds and she fired up. 

Lesson learned, neglect is a terrible thing. I let her sit too long and without paying any attention to the fuel.

Thanks all for the helpful information.

Mike G.


----------



## thepumpguysc (Jan 25, 2015)

Any time Mike, glad it worked out for you..
Happy tractoring..


----------

