John Deere 4520 Fuel Injectors

[raymand50]

Thank goodness I found this forum. I'm not very internet savy. I started having problems with engine surging, pulled hose off in front of tank and found snot like substance in hose, drained all fuel in tank, etc., primed but will not start with new fuel. Someone told me that I need to vent the injectors, but JD service manuel does not illustrate corrent location. Any help much apprectated. Thank you in advance Raymand50.

[Muhammad]

Welcome to TBN.

[JimRB]

I do not know your tractor. My little old JD 870 has a fuel strainer filter by the tank and a fuel filter up by the injection pump. Have changed the filters in these areas if your tractor has these? There are fuel cut off valves to help you change the filters. I would do the filter by the tank first then the one up by the injector pump.
https://jdparts.deere.com/servlet/co...quipmentSearch If that does not work go find their parts catalog.

[Briana03]

Hello & WELCOME to TBN!

I moved your thread to the John deere Owning/Operating Forum.

[JD5210]

The first thing is to get the tractor started then address the surge. Since JD made two 4520, I am going with this is the compact. I believe when they say vent, what they mean is to bleed the injectors. Before I would do that, I would blow out the lines if you can as the "snot" may have made it into the lines.

I would then insure the fuel tank is full, replace the fuel filter and fill the fuel filter before putting it on. Then prime the system, I would do this a couple times as manual suggests, if it does not start after the first prime. I have included the URL for JD parts, there is great illustrations of how things look. If still does not start, then search the internet or this web site on how to bleed the injectors. There are a number of videos on the web on this. Always nice to see how it is done before doing it.

John Deere - Parts Catalog

After you get it started post back and we can address the surge. How many hours on the tractor?

[raymand50]

Thanks for everyones help. The model 4520 I have is a 2008 year model COMPACT UTILITY tractor. When investigating on how to vent the INJECTORS, the two local JD dealers told me that they are not field serviceable. Most tractors injectors are located on the outside of the enjine. THIS MODEL HAS THE LOCATED UNDER THE VALVE COVER and require computer timed.

So back in September 2011 I had the local JD company pick up and solve the issue of not starting. So my tractor has been in their shop for FOUR months. And now it has supposedly beed repaired. FOUR NEW INJECTORS and 40 HOURS labor @ $76 per hour. I now have a bill of labor $3020. and JD will take catre of the parts under warranty.

I'm positive that if I had known this model would have such a high maintenance $$$$$$$$$$$$$$ I would not have purchased a JD.

Thanks again for your help.

[AKfish]

That is a bit of "Sticker-Kicker" shock..! I'd have to wonder, though. Why was it necessary to replace the injectors?

Did the "snot" (sounds like algae growth in the fuel) make it through the filters and into the injector pump and injectors? That would likely blow the tips off the ends of the injectors.

What feedback information did you get from the dealership mechanics?

AKfish

[dconine]

How many engine hours are on this machine?

That seems a little high on the labor repair hours to me. 40 Hrs?

[murphy1244]

40 Hours???? Heck I know people that could of rebuilt the whole top end in less than that....

[jenkinsph]

No way I can see to justify that much time to change the injectors. What does the "book" allow for this job? How much time is needed for a diagnosis if you know what the problem was before it entered the shop?

This assumes you told the dealer what you found and what you did to try to resolve the problem.