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656 Injection pump locked up and driveshaft broken


BluFlame11

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Hello! I am working on a 656 diesel for a friend who said it would not start back up after he was raking hay and shut it down for a brief period of time. After checking it our, I found we were not getting fuel to the injectors. On further testing, I found that the timing marks were not turning. I removed the pump to find the driveshaft snapped off and then I tried to turn the pump drive, it is locked up solid. Any idea what would cause this all of a sudden? Where can I get a replacement driveshaft? My search online did not really find any. Can I just replace the pump and driveshaft and be good to go? What else do I need to do before putting another pump on it? I have heard about maybe checking the nozzles? How is that done?

 

Thank you !

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10 minutes ago, BluFlame11 said:

Hello! I am working on a 656 diesel for a friend who said it would not start back up after he was raking hay and shut it down for a brief period of time. After checking it our, I found we were not getting fuel to the injectors. On further testing, I found that the timing marks were not turning. I removed the pump to find the driveshaft snapped off and then I tried to turn the pump drive, it is locked up solid. Any idea what would cause this all of a sudden? Where can I get a replacement driveshaft? My search online did not really find any. Can I just replace the pump and driveshaft and be good to go? What else do I need to do before putting another pump on it? I have heard about maybe checking the nozzles? How is that done?

 

Thank you !

Go with another complete pump Make sure your fuel is good those are lubricated by fuel lubricity only

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I believe it would be a good idea to check the fuel to make sure it didn’t get a slug of water mixed in or mis-fueled with gasoline.  Something caused the pump to seize.  Good luck.

 

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1 hour ago, ksfarmdude said:

Go with another complete pump Make sure your fuel is good those are lubricated by fuel lubricity only

 

29 minutes ago, axial_al said:

I believe it would be a good idea to check the fuel to make sure it didn’t get a slug of water mixed in or mis-fueled with gasoline.  Something caused the pump to seize.  Good luck.

 

Thank you for your replies!

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The hydraulic head has seized and locked up the pump.

When the head seizes, the drive shaft will intentionally break in that smaller machined spot rather than wreck the timing gears.

I have seen those heads seize for a reason but many times, you never really know why they locked up.

You need another good pump and driveshaft.,

Any pump shop will probably have both.

I have seen the idler gear bearings bad in a 706 that caused a head to seize.

Snap a vice grip on the old part of the driveshaft still in the engine.

Work it up and down and look for excessive play in the timing gears.

If normal, put a different pump on it and fire it up.

The hydraulic head runs on the thickness of a film of diesel fuel. Very tight tolerances. 

I am a big believer in Stanadyne Diesel Fuel Conditioner as it works. 

But a cup of 2 cycle oil in a tank of fuel should raise the lubricity to usable levels.

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27 minutes ago, Diesel Doctor said:

The hydraulic head has seized and locked up the pump.

When the head seizes, the drive shaft will intentionally break in that smaller machined spot rather than wreck the timing gears.

I have seen those heads seize for a reason but many times, you never really know why they locked up.

You need another good pump and driveshaft.,

Any pump shop will probably have both.

I have seen the idler gear bearings bad in a 706 that caused a head to seize.

Snap a vice grip on the old part of the driveshaft still in the engine.

Work it up and down and look for excessive play in the timing gears.

If normal, put a different pump on it and fire it up.

The hydraulic head runs on the thickness of a film of diesel fuel. Very tight tolerances. 

I am a big believer in Stanadyne Diesel Fuel Conditioner as it works. 

But a cup of 2 cycle oil in a tank of fuel should raise the lubricity to usable levels.

Thank you for this advice! I have wiggled the part of the shaft that remains and there does not seem to be any play in the gears/teeth. What's the easiest way to get the old shaft out? Do I unbolt the small cover directly in front of it? 

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Are all the parts of the filter housing still intact ?
post a picture of the filter, housing lid, and housing inside, please

In all my years, I think that I have only seen 2 pumps that have locked up from normal use -- that pump is pretty tolerant, as long as the filters are kept in good shape

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1 hour ago, HydroTek said:

Are all the parts of the filter housing still intact ?
post a picture of the filter, housing lid, and housing inside, please

In all my years, I think that I have only seen 2 pumps that have locked up from normal use -- that pump is pretty tolerant, as long as the filters are kept in good shape

Can't forget a stuck injector causing.  Had a CAV pump head trashed by a cheap Chinese knockoff pencil nozzle 

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21 minutes ago, Cdfarabaugh said:

Can't forget a stuck injector causing.  Had a CAV pump head trashed by a cheap Chinese knockoff pencil nozzle 

Highly unlikely with the outward opening nozzles in this engine. Appearance of portion of shaft that was in contact with fuel should be a clue.

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49 minutes ago, snoshoe said:

Highly unlikely with the outward opening nozzles in this engine. Appearance of portion of shaft that was in contact with fuel should be a clue.

Good observation....are you thinking it was contaminated fuel possibly? I see what you mean, but that was after I wiggled the shaft all around with grease all over my hands. I didn't take note of what it was like before.

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50 minutes ago, BluFlame11 said:

Good observation....are you thinking it was contaminated fuel possibly? I see what you mean, but that was after I wiggled the shaft all around with grease all over my hands. I didn't take note of what it was like before.

Short answer is yes but if that is grease then less likely. From here it sure looks like old fuel residue.

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2 hours ago, snoshoe said:

Highly unlikely with the outward opening nozzles in this engine. Appearance of portion of shaft that was in contact with fuel should be a clue.

True, but I'd definitely be having them checked.  

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Crappy thing also be sure you factor in paying full price and losing your core if doing an exchange (or getting sticker shock getting it done at a shop).  If I remember the last roosa with a trashed head was around a grand with another hydraulic head and new drives haft on top of what a pump normally is gone through.  

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29 minutes ago, Cdfarabaugh said:

Crappy thing also be sure you factor in paying full price and losing your core if doing an exchange (or getting sticker shock getting it done at a shop).  If I remember the last roosa with a trashed head was around a grand with another hydraulic head and new drives haft on top of what a pump normally is gone through.  

Here the "motions"  and some to  ,all  of the $35 seal kit = $1800>

Beyond the "normal" wear parts < $200 additional

That would qualify for a write off and buy another outright,before EVER even calling said "shops"

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The old contaminated sour fuel is definitely the cause of failure, can see it on the remaining shaft. These are just not happy living in sewage fuel. I've rebuilt several seized pumps because of this. I do still have used heads for these, but have had to buy new heads for 4 cylinder DB's. Just did one last week off a JD 6000 sprayer and it was 2400!

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I agree with the contaminated fuel.

But this is now a way of life with the low sulfur fuel.

Diesel fuel used to be an oily product and you never seen rust in a diesel pump.

One of the last Roosa Masters I tore down was covered with rust over all the steel governor parts.

That is your low sulfur fuel that causes this.

It appears that somewhere in the process of removing the sulfur they are oxygenating the fuel.

That oxygen in the fuel bonds to the steel and causes rust.

Diesel fuel treatments seems to be the only answer at stopping this.

 

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