Cummins QSB 5.9 fuel lift pump.

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driver0606

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Hello,
I suffered a temporary erratic loss of power recently that righted itself (so far!) after I stopped and restarted the engine. I have eliminated the filters and probably the fuel supply as the cause. Could it be the lift pump, please?
 
driver0606 said:
Hello,
I suffered a temporary erratic loss of power recently that righted itself (so far!) after I stopped and restarted the engine. I have eliminated the filters and probably the fuel supply as the cause. Could it be the lift pump, please?
Click to expand...

Latestarter1 is the forum expert on this engine.
 
driver0606 said:
Hello,
I suffered a temporary erratic loss of power recently that righted itself (so far!) after I stopped and restarted the engine. I have eliminated the filters and probably the fuel supply as the cause. Could it be the lift pump, please?
Click to expand...

Hi I have been traveling in Europe with a sick phone so not been looking in!

Can we get back to basics, please tell me exactly how you have eliminated your fuel filters.

QSB has electric lift pump, however engine will continue to run if lift pump fails but engines senses change in Delta 'P' and flags a fault code.

My biggest concern is that I hope you have NOT been pre filling fuel filters but simply keying on and allowing the electric pump to prime the filters which prevents any contaminants from entering the system.

Post your ESN and some more symptoms and we can get this bottomed.

Good luck
 
Hello Latestarter1, good to hear from you. My original post was=

You solve one problem and up comes another. Hey Ho, I guess that's boating.
I have just completed an hour's run in my Azimut 43 fitted with twin Cummins QSB 5.9. The fuel filters were newly changed. After about 30 minutes at 2400 revs/min., the starboard engine started to lose power and surge and then would only run smoothly at not more than about 1000 revs/min. I let it idle for a while at 600 and it stalled, but restarted easily. “Check engine” appeared on the display. Classic blocked fuel filter symptoms, but the filters were new and the Racor glass was clear. I switched it off for a few minutes, then restarted and it ran normally and cruised at 2400 for a further 20 minutes, so it could not be blocked filters.
Read more at http://www.ybw.com/forums/showthrea...-power-on-Cummins-QSB-5-9#6vfheubSOYM6KZzy.99

I did not pre fill the filters. I have drained some fuel from (nearly) the bottom of the tank which was clear. There is no drain right at the bottom.
Glad you are on the case.
 
driver0606 said:
Hello Latestarter1, good to hear from you. My original post was=

You solve one problem and up comes another. Hey Ho, I guess that's boating.
I have just completed an hour's run in my Azimut 43 fitted with twin Cummins QSB 5.9. The fuel filters were newly changed. After about 30 minutes at 2400 revs/min., the starboard engine started to lose power and surge and then would only run smoothly at not more than about 1000 revs/min. I let it idle for a while at 600 and it stalled, but restarted easily. “Check engine” appeared on the display. Classic blocked fuel filter symptoms, but the filters were new and the Racor glass was clear. I switched it off for a few minutes, then restarted and it ran normally and cruised at 2400 for a further 20 minutes, so it could not be blocked filters.
Read more at http://www.ybw.com/forums/showthrea...-power-on-Cummins-QSB-5-9#6vfheubSOYM6KZzy.99

I did not pre fill the filters. I have drained some fuel from (nearly) the bottom of the tank which was clear. There is no drain right at the bottom.
Glad you are on the case.
Click to expand...

Post me the ESN of troublesome engine please.
 
driver0606 said:
Oh. Thanks. The two engine nos. are 46548901 and 46549242. I can check tomorrow which one gave problems.
Click to expand...

No need to know which engine.

According to Cummins Quickserve.

Serial #: 46548901
Build Date: November 2, 2005 Rocky Mount/Charston USA
Model: QSB5.9-426 HO Engine Config: D403075MM14
Fuel Pump #: 3972815
Fuel Pump Cal Code: GY99
CPL: 8732

Before 2008/9 the transfer pump particularly on 24 volt engines could be troublesome. Pump rarely failed completely, but could go intermittent causing symptoms you describe, engine tends to run like a bag of crap and fuel consumption also suffers.

We beat up on Cummins pretty bad before the 2008 Round Britain Race as we were well aware of the issue.

I examined failed pumps, had them apart, beautifully made and no obvious cause of failure. One could reassemble the pump and in most it would work again! I have had an engine on the dyno with troublesome pump, 'somebody' gave it a whack and once fault codes cleared engine ran perfectly!

From 2009 the problem disappeared as if by magic, pump part number and supplier remained the same however new replacement pumps never suffered the same face as the originals and I have never experienced the problem with new engines post 2009.

I considered myself vindicated when the QSB 6.7 adopted the slightly different QSC arrangement.

New pump was $120 when it was playing up as Cummins reduced the price however it has gone back to $200 which must say something as well.

Part # of pump is 3968189.

Where are you located and do you intend changing out yourself??

Good luck
 
Latestarter1 said:
No need to know which engine.

According to Cummins Quickserve.

Serial #: 46548901
Build Date: November 2, 2005 Rocky Mount/Charston USA
Model: QSB5.9-426 HO Engine Config: D403075MM14
Fuel Pump #: 3972815
Fuel Pump Cal Code: GY99
CPL: 8732

Before 2008/9 the transfer pump particularly on 24 volt engines could be troublesome. Pump rarely failed completely, but could go intermittent causing symptoms you describe, engine tends to run like a bag of crap and fuel consumption also suffers.

We beat up on Cummins pretty bad before the 2008 Round Britain Race as we were well aware of the issue.

I examined failed pumps, had them apart, beautifully made and no obvious cause of failure. One could reassemble the pump and in most it would work again! I have had an engine on the dyno with troublesome pump, 'somebody' gave it a whack and once fault codes cleared engine ran perfectly!

From 2009 the problem disappeared as if by magic, pump part number and supplier remained the same however new replacement pumps never suffered the same face as the originals and I have never experienced the problem with new engines post 2009.

I considered myself vindicated when the QSB 6.7 adopted the slightly different QSC arrangement.

New pump was $120 when it was playing up as Cummins reduced the price however it has gone back to $200 which must say something as well.

Part # of pump is 3968189.

Where are you located and do you intend changing out yourself??

Good luck
Click to expand...

I remember that problem well in the run up to RB08, we had 24v pumps and Cummins only provided the alternative pumps days before the race, they fitted Racor pumps in the pre filters but I'm sure they have now been replaced again with some other on-engine pump, only problem we did have though, really impressed with the engines.
 
Hello,
Many thanks for the details.
The boat is in Menton, 06500, Cote d'Azur, France. I am often in the UK. I would consider fitting the lift pump myself, depending on the complexity and how certain it is the pump. Its quite difficult to find a reasonably priced engineer around here. Cummins want about 240 pus euros to come and put their tester on.
Regarding symptoms, when it was running badly, the fuel consumtion on the meter seemed erratic, but quite low. I have since run the engine at 1200 refv/min for about 3 hours (in roughish seas) with no problem.
 
driver0606 said:
Hello,
Many thanks for the details.
The boat is in Menton, 06500, Cote d'Azur, France. I am often in the UK. I would consider fitting the lift pump myself, depending on the complexity and how certain it is the pump. Its quite difficult to find a reasonably priced engineer around here. Cummins want about 240 pus euros to come and put their tester on.
Regarding symptoms, when it was running badly, the fuel consumtion on the meter seemed erratic, but quite low. I have since run the engine at 1200 refv/min for about 3 hours (in roughish seas) with no problem.
Click to expand...

Time for a plan..............

I learned that the pump when failing can sound perfect one day give you alarms the next day, perfectly the next and then back to more alarms and running like a bag of crap. If you have any fault codes of 2265 prime pump, or 559 low fuel pressure it is your pump.

Calibrated ear also works well in detecting the issue. A healthy pump hums away nicely a dying pump sounds like it is choking, no Insite tool required to detect that.

Ease replacing the pump depends very much on access as it is located on the back of the ECM cooling plate and you also need to remove the engine CAC to gain access. Nothing at all daunting, just looks it, should take about 11/2 hours.

Good chance to service your CAC whilst you are at it.

I do have some pictures of the pump location if you require.

Good luck.
 
Thanks latestarter1,
Presumably the lift pump is the same as the electrically driven priming pump and you have to be alongside it to hear it.
Where would I see those fault codes, please? The Smartcraft meter just said "Check engine" which was a statement of the obvious if ever there was one!
 
driver0606 said:
Thanks latestarter1,
Presumably the lift pump is the same as the electrically driven priming pump and you have to be alongside it to hear it.
Where would I see those fault codes, please? The Smartcraft meter just said "Check engine" which was a statement of the obvious if ever there was one!
Click to expand...
Yes, pump without being pedantic pump is actually a priming pump in order that fuel filters can be changed dry in order to prevent any contamination entering the system. The fact that engine runs like crap when pump plays up was actually unintended consequence.

Go into engine room and key the 'good' engine on you will hear a very distinct wrurr from the pump as it pressurises the filters, pump then cuts out. Now try the problem engine, pump may wrurr or sound like like it is choking or not run at all. Surprised you have not experienced the noise when changing filters as it is quite loud

I need to know what version of Smartcraft gauges you have, assume you do not have Smartcraft Diesel view??

Good luck

PS do not put a meter across the pump terminals, have had people reporting real wacky voltages that tell you nothing because pump runs on PWM signal.
 
Last edited:
When keyed, the pumps from both engines sounded similar. There was the wrurring noise, with some periods where it became louder and harsher on both pumps. Eventually the pumps switched off.

The materials lists for each engine shows a Smartcraft SPM and TAC, component 4081961
 

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Here is the rub, if you press the 'Mode' button and scroll through the small display window it will display 'active' faults, however from what you are telling me and the the way that these priming pumps go intermittently cranky fault code has likely gone 'inactive' and therefore not be displayed!

You have two options:

Simply change the pump and have done with it, season is nearly on us.

I have Cummins QuickCheck hand held device in the workshop, battery is a little suspect and not 100% sure if it has all the leads but I can check. If you really want to play I will check it out and may be able to send it to you against a small deposit.

I am well aware that dealers in Europe take no prisoners. Recently had simple rail pressure sensor failure in Italy, dealer came out with Insite diagnosed the fault. Dealer called on return to depot to confirm that the rail sensor was in stock, asked for CC details for advance payment as Insite calculates repair hours and they came out following day and replaced sensor.

If I were in Europe I would automatically set myself up with Cummins Insite, then you can be really armed and dangerous! PM me if you want to set yourself up,
 
MapisM said:
Just curious P, do you know if by chance there's anything like Cummins Insite also for Cat and MAN?
Click to expand...

I have contact who can set up CAT ET on your laptop, however obtaining the interface can be a little difficult other than from CAT distributors $$. As Cummins are very involved with Chinese manufacturers they have Inline 5 clones everywhere.

MAN like others Europeans generally share NOTHING!

However I will take a look, there is a Russian site which seems to claim to have most manufacturers software. Volvo Penta, do not ask!
 
All understood, many thanks. But don't bother checking further (not for myself, anyway).
ATM, it's still just a theoretical interest, because either CAT or MAN are the engines powering the boats I'm considering.
My current old tub also has CAT as you know, but finding an interface for a pair of 100% mechanical 3116 would be even more than a little difficult... :D
 
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