Stuck in Petersburg with bad lift pump....

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DDW

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Cummins QSB. Has a fuel lift pump installed in the worst possible place for service. Coming through the Wrangell Narrows, low pressure fuel warning followed by the engine faltering and dying mid channel in a narrow spot. Error code was low fuel pressure, was able to restart and run at reduced speed into Petersburg. Cummins mechanic is on vacation, no other expertise in town.

The lift pump sounds weak and quavery when it runs 60 seconds at key on and has for some time. Rather than proceed into more remote regions of AK I decided to replace it with a new spare I had on board. Cummins hides this pump behind the ECM cooling plate, which is behind the aftercooler, which is behind the fuel cooler all of which must come off. 6 hours later I have the new pump installed an everything reassembled. It sounds better, but after one or two cycles runs only 10 seconds before shutting down with an error 2266: lift pump high current. Cummins manual debug procedure ends in "replace pump". New pump coming from Anchorage but at least 3 days away.

It could be the new out of the box spare is bad. I do not want to wait 3 days, 6 hours more labor, and discover the problem is elsewhere. Is anyone familiar with the QSB lift pump issues (internet reports many)? Could there be something else that would cause the fuel pump to draw too much current? Filters seem good, and fuel visibly flows through them in the short time the pump runs. Cummins suggests that gelled fuel or something else jamming the pump will cause this, but it isn't that cold and the pump runs every time for a short while so not locked.
 
I wonder if there was a kink or some blockage in a fitting that slowed the fuel down causing the first symptoms. Is there a was to run two temp fuel lines and cycle fuel from a container to isolate the problem to the pump?
 
I wonder if there was a kink or some blockage in a fitting that slowed the fuel down causing the first symptoms. Is there a was to run two temp fuel lines and cycle fuel from a container to isolate the problem to the pump?

Contact Tony Athens at Sbar Marine. You may want to tell him up front you’re not looking for free advice.
 
Not knowing this engine my guess would be to look at the control for the pump. Is there a relay driving it or some external connections, plugs, etc. which could have some corrosion/resistance? If driven from the ECM I would expect some external relay.
 
Any vacuum to the pump? I wonder about restriction causing the first code then the new code if you were able to restart and run at a lower rpm.
 
I haven't heard of any lift pump issues on the QSB being discussed on the forums.

As noted, a call to Tony may be worth it. I believe he is semi retired, so one of the other guys may pick up. They may be willing to talk with you for a few minutes pro bono. I have paid Tony for his time on an hourly rate basis in the past. Just a couple hours, but was worth it. His shop may also be a good resource for sourcing parts if needed.
 
While you are waiting for the new pump, I'd go ahead and replace all fuel filters between the tank and lift pump. With a restriction, fuel may flow fine initially, but a vacuum may be building that subsequently slows it down.


Also check your fuel return line, and in particular make sure there isn't a valve that has accidentally been partially closed.
 
I'm assuming you contacted Piston and Rudder. Seems weird that Mike and Jason are on vacation at the height of fishing season. Would not find it hard to believe that they are very busy with the fleet (first priority around here). Wish I could help. If you need tools or transportation, let me know. What dock are you on? Will be leaving Sat. with sis and hubby for a week. 206-660-4503.

Tator
 
The ECM drives the pump directly. I've measured the current with a clamp ammeter, it is in fact well over the spec, 10A vs a <3 amp spec. The old pump when plugged into the same circuit (though not plumbed) draws about 2A. A vane pump should run with less amperage if the intake is blocked, shouldn't it? If the output was blocked, maybe? Also, the old pump ran the full 60 second cycle before I took it off with no overcurrent warning - would seem to eliminate plumbing problems?

The inlet is serviced by two tanks and two large Racors. Switching between them does not change the behavior, nor is any vacuum shown on the Racor gage. The lift pump is between the Racors on the suction side and the on-engine filter. All the lines are bespoke with banjo or face o-ring sealed fittings and very difficult to access so it isn't easy to plumb around or otherwise diddle. There are some capped ports on the engine fuel filter I am going to try to gage to see what the pressure is while the pump runs. I think I will change out the engine filter and see what happens, it is put on dry and the pump fills it so for at least that period the outlet is effectively open.
 
Wouldn’t a clogged primary filter or other obstruction cause the same alarm on the original pump? Sensors can lead or mislead.
Ok you beat me to it.
I would remove the engine filter, put a catch basin under it, and try the pump again.
 
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I haven't heard of any lift pump issues on the QSB being discussed on the forums.

As noted, a call to Tony may be worth it.
There are tons of reported problems with this pump, even on Tony's own forum. His advice in several threads there is: replace the pump.

I'm assuming you contacted Piston and Rudder. Seems weird that Mike and Jason are on vacation at the height of fishing season. Would not find it hard to believe that they are very busy with the fleet (first priority around here). Wish I could help. If you need tools or transportation, let me know. What dock are you on? Will be leaving Sat. with sis and hubby for a week. 206-660-4503.

Tator
Thanks for the offer. We are in #88 on south float of North harbor. I talked to Jason at some length, Mike is gone until the 10th and has taken the Insight laptop with him. However that will apparently only confirm what is already on the Smartcraft display, error 2266. The Cummins help line person just walked through the same debug matrix that is available from Quickserve resulting in "replace the pump". Blocked output was not something checked for in the debug matrix.

Now Cummins in Anchorage informs me that the pump did not get shipped yesterday as promised, which means rather than a Saturday delivery it will be Monday best case.
 
There are tons of reported problems with this pump, even on Tony's own forum. His advice in several threads there is: replace the pump.


Thanks for the offer. We are in #88 on south float of North harbor. I talked to Jason at some length, Mike is gone until the 10th and has taken the Insight laptop with him. However that will apparently only confirm what is already on the Smartcraft display, error 2266. The Cummins help line person just walked through the same debug matrix that is available from Quickserve resulting in "replace the pump". Blocked output was not something checked for in the debug matrix.

Now Cummins in Anchorage informs me that the pump did not get shipped yesterday as promised, which means rather than a Saturday delivery it will be Monday best case.

What QSB do you have the 5.9? I have the 6.7 and am not aware of any issues with the pump and that includes bending the ear of the local Cummins dealer who services the commercial fleet and Navy in our area. Tonys website also has reports of the raw water pump being a dud, and to replace that on the 5.9 with his SMX brand. I have spoken extensively to the noted Cummins dealer about that as well and they have noted no issues for the raw water pump for the 6.7. So you may want to be a bit more explicit in your posts regarding the engine model in the future when asking others for advice.
 
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The internet mythology of this suggests that after about 2010 they quit having problems (which the 6.7 post dates). Nevertheless, there is plenty of internet chatter about 6.7 lift pump problems.

Update: Called Anchorage Cummins to try to reroute the pump (which supposedly had not shipped yesterday) using a courier and Alaska Air Gold Streak counter-counter. They looked for my pump and discovered that it had gone yesterday (the tracking number I was originally given was the wrong one) and furthermore it had already been delivered to the Petersburg post office. I got the harbormaster to go check and sure enough it was there.

Now knowing exactly which tools, what order to remove, etc., I got the new pump in place in only 2 hours. You have to reassemble enough to try it, and now it runs for the full 60 seconds, no errors, and draws about 4 amps or less. So far so good!

I am strongly suspecting the new replacement pump I bought a year ago is an ersatz fake. It was from an online supplier claiming to be genuine Cummins OEM etc., came in a box printed with the Cummins logo and a label that looks exactly like the real one but for two small details: description is "oil pump" rather than "pump, fuel transfer"; and origin said US vs the real Cummins one which said China. There are a couple of other tell-tale signs: the conical rubber vibration dampeners that mount it were a loose fit (one very loose and could not be used) and did not have the Cummins part numbers molded in as both the original and new directly from Cummins ones do. There are some other very minor details that are different (but also different between the new and old Cummins part). It was packaged in a baggy moist with preservative oil which is kinda Chinese-like. New from Cummins one came in a sealed bag and was dry.

Will try a few more key cycles and then reinstall the aftercooler and fuel cooler and start the engine.
 
The internet mythology of this suggests that after about 2010 they quit having problems (which the 6.7 post dates). Nevertheless, there is plenty of internet chatter about 6.7 lift pump problems

The fuel system of the QSB 5.9 and 6.7 are configured differently, as noted by the side by side drawings on Tony’s site.

Regarding the “internet chatter of 6.7 fuel pump problems”, Copy, I will let the local Cummins dealer in SD know. They will have to get busy, because they have installed ALOT of QSB 6.7’s into Naval boats as well as recreational vessels without any reported pump failures (confirmed today), so they will be grateful to the internet for this information.
 
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There are tons of reported problems with this pump, even on Tony's own forum. His advice in several threads there is: replace the pump.





Thanks for the offer. We are in #88 on south float of North harbor. I talked to Jason at some length, Mike is gone until the 10th and has taken the Insight laptop with him. However that will apparently only confirm what is already on the Smartcraft display, error 2266. The Cummins help line person just walked through the same debug matrix that is available from Quickserve resulting in "replace the pump". Blocked output was not something checked for in the debug matrix.



Now Cummins in Anchorage informs me that the pump did not get shipped yesterday as promised, which means rather than a Saturday delivery it will be Monday best case.
Shipping from ANC is a minimum of 7 work days
 
Shipping from ANC is a minimum of 7 work days

This is the surprising thing. I called to order at about 11 AM. Cummins promised to get it into USPS Express Priority that day. I was told by everyone here that USPS would be much quicker than UPS or Fedex. There were some communication hickups back to me, but ultimately the USPS tracking shows it being picked up at about 4PM, leaving Anchorage late night, arriving Petersburg at 9AM, and put in the PO box at 10AM. I had expected 3 days, and if it had slipped a day, 4 days because Sunday is in there somewhere. In fact it was overnight.

The alternative I learned was to contact AMS Couriers who will for a reasonable fee fetch the package and take it to Alaskan Airlines cargo desk which would have gotten it here on the next flight. Total cost around $100. As the flight today had already left it would have been tomorrow. By the time I figured this out, I discovered that the package was already in the Petersburg post office. The harbormaster made a special trip up there and fetched it for me.

The second R&R took only about 3 hours, now knowing exactly what had to come off and in what order, and which tools were required, and which worked best. I think I could improve on that by another 1/2 hour next time maybe. Still not the sort of thing you'd want to do in a rolling seaway!

Several key cycles and all is well and as it should be. Engine starts and runs smoothly, keeping my fingers crossed and heading north in the morning.
 
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Not useful in this situation, but Fisheries can arrange for GoldStreak too, which can be handy in AK (or Hawaii).

For those wondering, GoldStreak is an Alaska Airlines cargo service. Cargo goes on the next flight, but it must be dropped off at an Alaska Air cargo terminal and picked up at the destination Alaska Air cargo terminal. Like a passenger, GoldStreak cargo must get to the airport 60 minutes before flight departure. Usually not the cheapest option, but sometimes worth it to avoid long delays associated with shipping beyond the lower 48.
 
Contact Tony Athens at Sbar Marine. You may want to tell him up front you’re not looking for free advice.

They now provide remote consulting on an hourly basis. It isn't instant satisfaction, but it works. Just to get home, can McGyver a pump, between the filters and the lift pump, to assist/replace the failing lift pump?
 
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I once tried to get stuck in Petersburg in the early 70’s.

I was northbound out of Prince Rupert bound for Juneau but upon arriving at Petersburg I wanted to stay there. Tried to talk the Oil service there into hireing me as truck driver but since I had been a shop teacher for two years he assumed I’d be up and gone as soon as another teaching job came along .. so he refused to hire me to fill his truck driver vacancy.

Never did return to teaching but Chris and I wanted to buy a house on the beach in the bottom of W narrows. We finally decided to move on but Petersburg was high in our hearts.
Later after leaving Thorne Bay we again looked at P burg. But decided the same thing would happen as happened in Thorne Bay.

Still would love to live in P burg … but not w/o a boat.
 
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So in K-Town the Cummins repair shop have the shipping figured out. My genny parts were ordered as "emergency fill". Came from Memphis in 2 days. Awesome
 
According to post#17 DDW got his new unit shipped in and installed. He departed Petersburg on the 8th. Good job!!
 
Cummins QSB. Has a fuel lift pump installed in the worst possible place for service. Coming through the Wrangell Narrows, low pressure fuel warning followed by the engine faltering and dying mid channel in a narrow spot. Error code was low fuel pressure, was able to restart and run at reduced speed into Petersburg. Cummins mechanic is on vacation, no other expertise in town.

The lift pump sounds weak and quavery when it runs 60 seconds at key on and has for some time. Rather than proceed into more remote regions of AK I decided to replace it with a new spare I had on board. Cummins hides this pump behind the ECM cooling plate, which is behind the aftercooler, which is behind the fuel cooler all of which must come off. 6 hours later I have the new pump installed an everything reassembled. It sounds better, but after one or two cycles runs only 10 seconds before shutting down with an error 2266: lift pump high current. Cummins manual debug procedure ends in "replace pump". New pump coming from Anchorage but at least 3 days away.

It could be the new out of the box spare is bad. I do not want to wait 3 days, 6 hours more labor, and discover the problem is elsewhere. Is anyone familiar with the QSB lift pump issues (internet reports many)? Could there be something else that would cause the fuel pump to draw too much current? Filters seem good, and fuel visibly flows through them in the short time the pump runs. Cummins suggests that gelled fuel or something else jamming the pump will cause this, but it isn't that cold and the pump runs every time for a short while so not locked.


I am not familiar with the setup, but if you OHM out the pump and calculate the amperage draw using Ohm's law, you could see if it is the pump itself or another problem in the system. The odds are 2 pumps aren't bad, especially a new one. But that said, new parts these days are more questionable.
 
Epilog:

We have arrived in Juneau after a tour of the Tracy Arm glaciers and a day of rest in Taku Harbor letting a bit of a blow go by. Have had no further trouble with the pump - so far....

Regarding a McGyver lashup: It could probably be done, I think anything that could deliver sufficient fuel to the HP injection pump at say 10 psi would work. But practically, the hoses are all swaged metal jacked with either banjo or face sealing o-rings, you'd have to duplicate those or cut them up. Starving the HP pump of fuel is said to cause its failure, and it is a $5000 pump, not a $360 pump, so there might be risk.

Regarding 12 vs 24V pumps: all three pumps I have ohm about the same at around 1.0 - 1.5 ohms, but as has been previously mentioned with DC motors that doesn't tell you much. In this vintage of engine, the 24V engine was supplied with a 24 -> 12V regulator to run the pump, in more recent engines there was a 24V version. I would have expected a 24V pump run on 12V to draw less current (and run slower), not more. This is a 12V engine. The bad "new" pump has a laser etching on its body indicating 12V. Complicating things, the ECM powers the pump and does so with a PWM signal - no further color on that from Cummins.

I was told by the Petersburg post office that stuff sent express from Anchorage to either Petersburg or Ketchikan will get there very fast, something about them being postal hubs. When an inventory check was done, the Cummins factory in Memphis had none, but Anchorage had 6.
 
Some instructions I posted on the ATOG users group, but useful for anyone with a QSB5.9. First try took nearly 6 hours, second one about 3, I'd be surprised if anyone can do a good job of it in less than about 2.5. No special tools or skills required, but not something I'd choose to do rolling around in a seaway.

1) Flush engine raw water system with fresh - not strictly necessary but results in all your spills being fresh water rather than salt. Place absorbent under area to catch water and diesel spillage.

2) Drain aftercooler from lower pencil zinc port. About 1 gallon will come out. (You did shut off the seacock, right?)

3) Depower engine at CAM Breaker, on my boat this was located in the tank room at the forward bulkhead. Loosen the screws and pull out what looks like a very large spade fuse. The Engine switch will not depower the ECM, only the starter motor.

4) Remove the fuel cooler by loosening hose clamps at the raw pump and aftercooler, this can be laid down out of the way without removing the fuel hoses.

5) Remove the afterooler - this looks like it just *might* be unnecessary, and I tried for a long time to not do it, but it is actually necessary. Loosen the hose clamps at the air inlet and outlet, and the water outlet at the top. The air inlet connects to a tube to the turbo, it is easier to take off and reinstall if you loose the hose clamp at the turbo, pull that off, then pull it off from the aftercooler. The water hose can be pulled loose without difficulty. The air outlet connects to the intake manifold, and the aftercooler is best pulled out of this as it is removed since there is no flexibility at that end. I found the easiest way to remove it was to remove the 12 pt bolt holding the forward bracket to the block (which also secures the fuel pump wire, 10mm wrench), then loosen the two large bolts aft and underneath with a 15 mm wrench. Then reaching around behind the top remaining bracket, remove the hidden bolts with a 13mm wrench and some swearing. This bracket is fastened with two readily visible bolts on top, one of which is diabolically blocked from removal by the #5 injector pipe. Once the hidden bolts are backed off a little I could reach them by hand and spin them out, jiggling the aftercooler a bit to unload them. With those out, remove one of the larger bolts on the bottom bracket and screw it into a second set of holes just below on the bell housing. This allows the aftercooler to rest on that while you wrestle with it. Unscrew the remaining bolt and supporting the weight, remove the aftercooler (about 35 lbs maybe?) and set aside on the carpet you prepared to receive it. If it has not been removed recently, getting the hoses unstuck with a tool of some kind first will make it much easier. The best tool for this I have found is a cotter key remover, also sometimes known as a windshield installation tool and occasionally even as a hose remover.

6) Remove power leads to ECM using a 7/16 wrench. Be vary careful, Cummins in their wisdom has applied some kind of hard black substance which makes the nuts difficult to turn, and to my surprise the studs are soft brass and twist off with ease requiring another repair!

6) Unplug the three large connectors with a 4mm allen key, unscrewing this automatically ejects the connector. There is another smaller one with a locking tab as well. Remove the three nuts securing the bottom of the ECM cooling plate (13 mm wrench), this will release the Jubilee clips holding the wiring harness and allow it to drop down out of the way.

7) Remove the three nuts securing the SIM module (10 mm wrench) and the washers behind them. The electrical plug for this has a securing tab, which itself is secured by another plastic safety. Pull the SIM module off and find the bolt securing a grounding strap underneath (10 mm 12 pt wrench). It might be possible to remove the grounding strap from the block end, not clear that is any easier.

8) Remove the top bolt securing the ECM plate, there is a spacer behind the plate which will drop as you remove the bolt unless you catch it.

9) Undo the fuel hose to the upper aft corner of the ECM cooling plenum, this requires a 7/8 open end or largish Crescent wrench. The connection is a face sealing o-ring and should not be terribly tight. Expect a small amount of diesel spillage. It may be possible to get to the pump without removing this, but it certainly makes it easier to undo it. See that the o-ring remains in place on the plenum fitting face groove for reassembly.

10) Wiggle the ECM plate free of the lower three studs, pull it down and under the hard high pressure fuel line going to the common rail, then pull out a little and hinge to port and forward like opening a book. The remaining lines should flex enough to gain access, and now the pump is finally visible! I was able to tie the plate off to the ladder through the top mounting hole to work on it, resting the bottom on the engine stringer.

11) There are four small bolts securing the fuel pump clamps. Loosen them all, and remove the top ones and flip the clamps down. The inlet and outlet are banjo fittings requiring a 17 mm wrench. The pump has an obvious small hex on its body, but this is useless for loosening the banjo fittings, instead use the large thin hex shapes by sliding the rubber vibration dampeners away from them - again a largish Crescent wrench is required. The banjos are not particularly tight, what looks like crush washers are actually bonded o-ring washers. Remove the aft one first and expect perhaps 4 oz of diesel to come out - enough you will want a small cup. Encourage it to drain by tilting the aft end down and shaking it. Then remove the front banjo and you now have the pump free. With practice you are now about 1 1/2 hours in.

12) The new part number for the pump is 5260632 superseding others. I recommend buying directly from Cummins USA parts even at the high price, there seem to be many fakes about and there is too much labor involved to chance it as I did. While you are ordering this, get four new bonded sealing washers, 3963990. The Cummins price for all of that was $386. “Genuine Cummins OEM” pumps can be had on eBay for <$100, but ‘you takes your chance’.

13) Reassembly is the reverse. I reinstalled the pump and ECM plate, hooked up the wiring and fuel hoses, powered up the engine, and ran a few key on cycles - don’t start the engine - before reinstalling the aftercooler and fuel cooler. It should bleat that plaintiff tone for 60 seconds, then stop, with no errors indicated on Smartcraft. You can almost still check for fuel leaks at this time, they are pretty much buried later. Double check that all the bolts and particularly all the hose clamps are tight before you start the engine, and check again after a short period of operation.
 
Some instructions I posted on the ATOG users group, but useful for anyone with a QSB5.9. First try took nearly 6 hours, second one about 3, I'd be surprised if anyone can do a good job of it in less than about 2.5. No special tools or skills required, but not something I'd choose to do rolling around in a seaway.

1) Flush engine raw water system with fresh - not strictly necessary but results in all your spills being fresh water rather than salt. Place absorbent under area to catch water and diesel spillage.

2) Drain aftercooler from lower pencil zinc port. About 1 gallon will come out. (You did shut off the seacock, right?)

3) Depower engine at CAM Breaker, on my boat this was located in the tank room at the forward bulkhead. Loosen the screws and pull out what looks like a very large spade fuse. The Engine switch will not depower the ECM, only the starter motor.

4) Remove the fuel cooler by loosening hose clamps at the raw pump and aftercooler, this can be laid down out of the way without removing the fuel hoses.

5) Remove the afterooler - this looks like it just *might* be unnecessary, and I tried for a long time to not do it, but it is actually necessary. Loosen the hose clamps at the air inlet and outlet, and the water outlet at the top. The air inlet connects to a tube to the turbo, it is easier to take off and reinstall if you loose the hose clamp at the turbo, pull that off, then pull it off from the aftercooler. The water hose can be pulled loose without difficulty. The air outlet connects to the intake manifold, and the aftercooler is best pulled out of this as it is removed since there is no flexibility at that end. I found the easiest way to remove it was to remove the 12 pt bolt holding the forward bracket to the block (which also secures the fuel pump wire, 10mm wrench), then loosen the two large bolts aft and underneath with a 15 mm wrench. Then reaching around behind the top remaining bracket, remove the hidden bolts with a 13mm wrench and some swearing. This bracket is fastened with two readily visible bolts on top, one of which is diabolically blocked from removal by the #5 injector pipe. Once the hidden bolts are backed off a little I could reach them by hand and spin them out, jiggling the aftercooler a bit to unload them. With those out, remove one of the larger bolts on the bottom bracket and screw it into a second set of holes just below on the bell housing. This allows the aftercooler to rest on that while you wrestle with it. Unscrew the remaining bolt and supporting the weight, remove the aftercooler (about 35 lbs maybe?) and set aside on the carpet you prepared to receive it. If it has not been removed recently, getting the hoses unstuck with a tool of some kind first will make it much easier. The best tool for this I have found is a cotter key remover, also sometimes known as a windshield installation tool and occasionally even as a hose remover.

6) Remove power leads to ECM using a 7/16 wrench. Be vary careful, Cummins in their wisdom has applied some kind of hard black substance which makes the nuts difficult to turn, and to my surprise the studs are soft brass and twist off with ease requiring another repair!

6) Unplug the three large connectors with a 4mm allen key, unscrewing this automatically ejects the connector. There is another smaller one with a locking tab as well. Remove the three nuts securing the bottom of the ECM cooling plate (13 mm wrench), this will release the Jubilee clips holding the wiring harness and allow it to drop down out of the way.

7) Remove the three nuts securing the SIM module (10 mm wrench) and the washers behind them. The electrical plug for this has a securing tab, which itself is secured by another plastic safety. Pull the SIM module off and find the bolt securing a grounding strap underneath (10 mm 12 pt wrench). It might be possible to remove the grounding strap from the block end, not clear that is any easier.

8) Remove the top bolt securing the ECM plate, there is a spacer behind the plate which will drop as you remove the bolt unless you catch it.

9) Undo the fuel hose to the upper aft corner of the ECM cooling plenum, this requires a 7/8 open end or largish Crescent wrench. The connection is a face sealing o-ring and should not be terribly tight. Expect a small amount of diesel spillage. It may be possible to get to the pump without removing this, but it certainly makes it easier to undo it. See that the o-ring remains in place on the plenum fitting face groove for reassembly.

10) Wiggle the ECM plate free of the lower three studs, pull it down and under the hard high pressure fuel line going to the common rail, then pull out a little and hinge to port and forward like opening a book. The remaining lines should flex enough to gain access, and now the pump is finally visible! I was able to tie the plate off to the ladder through the top mounting hole to work on it, resting the bottom on the engine stringer.

11) There are four small bolts securing the fuel pump clamps. Loosen them all, and remove the top ones and flip the clamps down. The inlet and outlet are banjo fittings requiring a 17 mm wrench. The pump has an obvious small hex on its body, but this is useless for loosening the banjo fittings, instead use the large thin hex shapes by sliding the rubber vibration dampeners away from them - again a largish Crescent wrench is required. The banjos are not particularly tight, what looks like crush washers are actually bonded o-ring washers. Remove the aft one first and expect perhaps 4 oz of diesel to come out - enough you will want a small cup. Encourage it to drain by tilting the aft end down and shaking it. Then remove the front banjo and you now have the pump free. With practice you are now about 1 1/2 hours in.

12) The new part number for the pump is 5260632 superseding others. I recommend buying directly from Cummins USA parts even at the high price, there seem to be many fakes about and there is too much labor involved to chance it as I did. While you are ordering this, get four new bonded sealing washers, 3963990. The Cummins price for all of that was $386. “Genuine Cummins OEM” pumps can be had on eBay for <$100, but ‘you takes your chance’.

13) Reassembly is the reverse. I reinstalled the pump and ECM plate, hooked up the wiring and fuel hoses, powered up the engine, and ran a few key on cycles - don’t start the engine - before reinstalling the aftercooler and fuel cooler. It should bleat that plaintiff tone for 60 seconds, then stop, with no errors indicated on Smartcraft. You can almost still check for fuel leaks at this time, they are pretty much buried later. Double check that all the bolts and particularly all the hose clamps are tight before you start the engine, and check again after a short period of operation.
 
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