# John Deere 500A Loader Backhoe new to forum



## nlneilson (Jan 29, 2017)

I have a John Deere 500A Loader Backhoe 
It has been a good piece of equipment for several years.
Now I need to remove the injector pump.

Where is the timing mark ??, on the flywheel or the front pully ??
Any pictures or a few pages of the service manual would help.

Neil


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## sixbales (May 18, 2011)

Howdy nlneilson,

Welcome to the tractor forum.

There is an excellent post on this forum entitled *John Deere JD 500 A injection pump*, with response by *TraderMark*. You can find it by searching this forum or the internet. 

John Deere JD 500 A injection pump - Tractor Forum

www.tractorforum.com/f181/john-deere-jd-500-injection... 

You can also find a service manual for your 500A which will cover the injection pump removal/replacement.


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## nlneilson (Jan 29, 2017)

Hi sixbales
Thanks for the quick response.
Both of the links in your post returns "page not found"
a google search found a post by TraderMark. Some good points but I need more info so I ordered a Service manual I&T on ebay for $61.88, that is paper, is there a place on this forum to download a digital manual?

So far I don't know if the timing marks are on the flywheel or the front pulley, how to move the injector lines to remove the pump, etc.


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## TraderMark (Nov 15, 2011)

Hi nlneilson,
Welcome!
Those old 500A loaders with the upright pump on the 270 engine are a bugger to work on.
My advice to you is to just remove the injector lines completely. They wind and twist up around the manifold and have some clamps that hold the lines together in a cluster and I usually found it was easier and saved time in the long run to just remove the lines completely one at a time.

If the engine was running and performing satisfactorily you don't need the timing marks on the flywheel. 

Scribe a line on the pump housing and the engine block so you can line the pump body back up exactly where it was.

Remove the little window from the injection pump. It's just to the left of the screw on the bottom that has the wire through it. There are two small flat head screws that need to be removed to get the window cover off.

Be careful. There's quite a bit of diesel inside the injection pump and you'll be releasing it all so have a bucket handy. I'd say there's probably a pint or so inside the pump.

Once you have the window open and all the fuel is out, turn the engine until you see the two lines inside the pump line up. When they line up, you can pull the pump out. Make certain there's no way for anyone to turn the engine while the pump is out. Disconnect the battery if you haven't already so the key can't be accidentally used to engage the starter.

After your rebuild/repair, remove the window again, make sure the marks are aligned and slip the pump back in.

HTH,
Mark


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## TraderMark (Nov 15, 2011)

I'll try and get this image to show here.


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## nlneilson (Jan 29, 2017)

THANKS Mark
I appreciate the information.

The tractor started and ran good before.
There was about a half inch of real gooey sludge in the bottom of the fuel tank.
Even with the two spin-on fuel filters I am thinking the goo got into the injector pump and the piston is stuck in the cylinder.
I hooked up a hand pump with injector cleaner and a gauge and put 100 psi through the filters and into the injector pump. I loosened three of the injector lines at the pump that I could get to. Cranked the engine over. The pressure stayed at 100 psi and no fuel came out the loosened injector lines.

For years it started and I could do the jobs I wanted. I miss being able to use it.


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