john deere 6415 starts hard

[namesray]

i am at work and we have a john deere 6415 tractor/side boom mower that starts hard after it sits for a day or so. it turns over ok, but will not fire until after it turns over alot. once it does start, it puts out grey smoke then runs fine. also, after it has been started for the day, it starts fine for any other starts that day. seems like it may be loosing prime? any one out there have any ideas? engine is diesel, 4.5l. model 4045. also, does anyone know if these 6415 had this common problem? maybe a tip on where to start? thanks in advance for any help.

 

[Harry in Ky]

I see your post has a number of viewers but no takers. I agree your problem seems to be fuel leaking off while the engine is not running. As I am not a bonafide Deere Man, I don't know every version of every model by heart, so I'm forced to look at the pictures. The parts pages I visited show more than one possible fuel system, of course, and we don't know which of them is yours. All those I saw show an electric pump. One version shows it mounted below the fuel filters, with hoses routed so fuel is pumped from the tank through a check valve and into the primary filter, to the pump and under pressure through the secondary filter to the injection pump. All the others show a pump mounted in the tank, which supplies fuel under pressure throughout. I did not see a check valve listed anywhere with the internal pumps, so I suspect the pump has check valves built in, which could be your problem. I would suggest you open the bleed vents on your fuel filter bases on your next attempt, turn the key on and see what happens. If it's true to form, you will soon get a spurt of air and then fuel from each in turn. Close the vents and try to start the engine. It should start far quicker than it has been. You might also inspect the fuel lines for condition and hose clamps for tightness, as any air leaks will contribute to fuel bleed off. If everything external looks airtight, you might consider pulling the pump out for inspection, assuming you have an internal pump

 

[jd110]

Most likely cause is dry rotted fuel lines. The rubber fuel lines from the tank to the filter/s tend to deteriorate and allows the fuel to drain back. If you replace all the rubber fuel lines, I'm betting your problem will be cured. Gates now markets hose called Barricade. It is supposed to hold up better with todays fuels. Do you have one or two fuel filters?

 

[DABSGT]

Check the injectors could have a partial blockage or maybe a leak

 

[cowski]

the check valve may be letting the fuel leak back into the tank,letting air into the system.this can cause hard cranking.

 

[balernbud]

check the pickup tube that is in the fuel tank these are plastic and have a history of cracking so you suck lots of air along with the fuel. If it has a sediment bowl you'll see air in it when you first start cranking the engine over.

 

[namesray]

thanks for the replies. we are starting with the tips you gave. one of the fuel filters seems to have a gap on one side more then the other side where it screws on. just a very slight difference. thinking this might also be it, but there is no fuel seapage/residue on it as might be expected if it was leaking off there. actually can't find any evidence of wet fuel residue indicating a small hole/leak on any fuel lines, but they do look weathered a little bit. that might point more to a check valve??? will let you all know if we find anything out. by the way if anyone is still wondering, it is the version with the electric pump mounted below the fuel filters, with hoses routed through two fuel filters to the injection pump.

 

[namesray]

just a final note to close this thread out, we found a fuel line to a fuel cooler/radiator that was wet on the outside just a tiny bit. (i never heard of a "fuel" cooler, but i swear this tractor has one) the fuel radiator fins in one corner also had some slight residue after further inspection. anyway the mechanic has temporarily by-passed this fuel cooler for now and the tractor fires up quick every single time. so we think we have found the problem. thanks for all your help and replys.

 

[Zebrafive]

Since I have a 6415, could you post a picture of this fuel cooler? Or tell me how to check my tractor for one? Maybe where it's located in the JD parts catalog? Thanks :thumbsup:

 

[Tx Jim]

I'd like to see a photo also. I can not envision a need for a diesel fuel cooler plus I couldn't find one listed in the parts catalog.

 

[Zebrafive]

I think Deere offers a fuel heater, maybe that's it

 

[jd110]

The newer 6415 with Tier II engine uses a fuel cooler. it is mounted above the battery, in front of the radiator as shown in this illustration. #35

 

[namesray]

The newer 6415 with Tier II engine uses a fuel cooler. it is mounted above the battery, in front of the radiator as shown in this illustration. #35

i am sorry to report that i am NOT very good with computers. i have no idea how to put a picture on here. but the illustration in jd110 post is the correct setup with the fuel cooler. it is just a little radiator in front of the coolant radiator attached to a bracket. at first look i thought it was a modification, but all the brackets and the setup looks like it was stock. just a question, why would a tractor need a fuel cooler?

 

[Tx Jim]

just a question, why would a tractor need a fuel cooler?

The only reason I can think of the need for a fuel cooler is to help meet the governments newer emission requirements of diesel engines.

A diesel fuel cooler in sub freezing temperatures sounds like a good EPA idea.:laughing:

I'm a computer dummy also but my 10 yr old Granddaughter showed me a couple months ago how to download a photo on the internet. Actually it's fairly easy now.

 

[Tx Jim]

The newer 6415 with Tier II engine uses a fuel cooler. it is mounted above the battery, in front of the radiator as shown in this illustration. #35

Thanks with the aid of your photo I found the cooler part #AL159242

 

[Zebrafive]

The newer 6415 with Tier II engine uses a fuel cooler. it is mounted above the battery, in front of the radiator as shown in this illustration. #35

I'll have to see if my 6415 has one, now that I know where to look.

Is there a serial number break when this was first put on?

 

[Edward. S]

Since I have a 6415, could you post a picture of this fuel cooler? Or tell me how to check my tractor for one? Maybe where it's located in the JD parts catalog? Thanks :thumbsup:

By the looks of hearing this.. Its the little radiator thats the size of a pop can just a bit behind the battery and up a bit. I have one of these on my 6420. Well I didn't know that there was a picture describing it. But my 6420 was getting so much air in the fuel system that it was getting 83 PTO HP on the dyno and thats 7 HP under what its rated. Say good bye to power with air in your fuel lines.

 

[Tx Jim]

I'll have to see if my 6415 has one, now that I know where to look.

Is there a serial number break when this was first put on?

I don't see a SN break in the parts catalog only this at the top of the page with part #s & descriptions where the cooler is listed. FUEL HOSES (WITH TIER II ENGINE). I asked about the need for an fuel cooler on another tractor forum and the tech's stated it was required on the common rail type injectors because of the heat generated in the return fuel.

 

[Zebrafive]

I'll have to see if my 6415 has one, now that I know where to look.

Is there a serial number break when this was first put on?

Finally checked my 6415. It has the fuel cooler, so I must have tier 2 engine with common rail injectors.

If any one still wants a picture I can take one and post it.

 

[Zebrafive]

Pictures of the fuel cooler on my 6415