Hard to start fendt 820

[westfield]

Hi I've got a 9800hr 820 with a starting issue. When starting it winds over for longer than normal and even when warm isn't like normal. I've also noticed it's slightly pressurising the diesel tank seems to be going fine the filters are all recently changed. The only thing different is I've replaced the filter unit with the lift pump in it as the plunger shaft got damaged on it this could all be a coincidence or something I've done?

 

[phillipe]

Hi I've got a 9800hr 820 with a starting issue. When starting it winds over for longer than normal and even when warm isn't like normal. I've also noticed it's slightly pressurising the diesel tank seems to be going fine the filters are all recently changed. The only thing different is I've replaced the filter unit with the lift pump in it as the plunger shaft got damaged on it this could all be a coincidence or something I've done?

letting a bit or air in ? where you changed the filter unit the gasket not sat quite right ?

 

[westfield]

letting a bit or air in ? where you changed the filter unit the gasket not sat quite right ?

I've checked all that fairly sure it's all ok the tank pressurising is a strange one

 

[phillipe]

I've checked all that fairly sure it's all ok the tank pressurising is a strange one

that what it seems tho ,

 

[Timbo]

Common rail or unit injectors on this one?

 

[Deerefarmer]

Don't know if this will apply to your model or not but the crank speed sensor can make them act like your describing if it's going bad. I'm not familiar with the 820 tho probably a bit different than the 828s

 

[Hesston4860s]

It’s probably got to much fuel in the tank, you’ll need to drain some off !.















Sorry couldn’t resist !.

 

[TripleSix]

Check the fuel tank breather.

Try it with the cap off or loosened...

 

[Boysground]

It doesn't account for the fuel tank issue but just check all the rubber fuel hoses. Have just had starting trouble on a 716 and it was perished hoses.

Bg

 

[westfield]

Thanks for all the replies if it wasn't pressurising the tank I would assume it's airing up somewhere its common rail engine someone did mention the injectors failing and back pressurising the return fuel line?

 

[Zetor]

Thanks for all the replies if it wasn't pressurising the tank I would assume it's airing up somewhere its common rail engine someone did mention the injectors failing and back pressurising the return fuel line?

Have you tried priming the hand pump before you try and start it?
Have you ever replaced the injectors?

 

[combinedoctor]

come on guys, where are all the very loud Fendt experts? loads of you on here when your slating other brands!
My guess would be injector pump.

 

[Deerefarmer]

@westfield you can remove injector return line and collect the fuel in say 30 seconds how much do you get? Does this tractor start at all on it's own or does it require help from a can? I assume you checked the tank vent. Ps let us know what you find ,i find it very educational for myself

 

[Banana Bar]

Thanks for all the replies if it wasn't pressurising the tank I would assume it's airing up somewhere its common rail engine someone did mention the injectors failing and back pressurising the return fuel line?

I think injectors will be the problem

 

[Zetor]

I think injectors will be the problem

You're probably right but best to check the simples first, £3k for a new set!!

 

[Yale]

come on guys, where are all the very loud Fendt experts? loads of you on here when your slating other brands!
My guess would be injector pump.

Don’t be silly.

They never break down,no one will have any experience of any issues.

 

[phillipe]

How it only started to have problems after changing the lift pump ?,i dont belive in coincidence

 

[Kevtherev]

Check it’s not the new lift pump sounds like there’s air getting in and allowing the fuel to run back to tank.
Had a tractor pressurise the tank and it was the fuel lines perishing.

 

[Morph]

Do these tractors have any kind of diagnostic port than can be accessed other than by dealer? On trucks/cars you would just read of the rail pressure whilst cranking.

 

[fergiedoctor]

Have a look at the belt driven lift pump and check for any play in the shaft or signs of fuel leakage, remove the fuel filter cartridge on the side of the engine and also check for the presence of any iron filings, if found this would also indicate a worn pump.