1998 Cummins 330hp main injector pump and lift pump

[speck]

On the way in to have generator and engine serviced I got a fault message about fuel pressure incorrect or intermittent.  Just got quote for lift pump and main fuel pump, $8500.  Is that about right?

[wolfe10]

It may be correct.

BUT, that is assuming the very worse.

Start by replacing both fuel filters-- a clogged filter will reduce fuel flow and can cause low pressure.

Then if still a problem, replace the lift pump.

Yes, if fuel pressure has been low for awhile, it can damage the injection pump.  But, that is NOT where I would start.

[manholt]

Is it a Cummins shop or Sam the Tech.  Go with Brett.

[speck]

5 hours ago, wolfe10 said:

It may be correct.

BUT, that is assuming the very worse.

Start by replacing both fuel filters-- a clogged filter will reduce fuel flow and can cause low pressure.

Then if still a problem, replace the lift pump.

Yes, if fuel pressure has been low for awhile, it can damage the injection pump.  But, that is NOT where I would start.

Thanks for the comments.

[speck]

4 hours ago, manholt said:

Is it a Cummins shop or Sam the Tech.  Go with Brett.

It is a shop authorized to do Freightliner warranty work.  This isn't under warranty.  Hard to find good service shop here in Colorado Springs ☹️.  This is the 5th shop I have been to in the past 3 yrs.

[manholt]

Cummins, Denver...right up the road.

[rsbilledwards]

Do what  Brett suggests and then call Dave Atherton 605 999 0720 and have a talk. Great guy, retired CAT/Cummins master trouble shooter. He is the Ask Dave host in the FMCA RV Diesel Club.

[wolfe10]

Link to Dave's part of the Diesel RV Club Forum: http://forum.dieselrvclub.org/index.php/board,100.0.html

[rayin]

The lift pump only runs for approx. 30 seconds(each time the key is turned on) to pressurize the injector pump, then it(inj pump) does all the work of pulling fuel through the filters and pumping it into the injectors, all the way from the tank.  When the filters become restricted, it shortens the life-span of the injector pump.

The lift pump is known for loose mounting bolts (3), which causes an air leak.  One guy experienced that, and after re-torquing the bolts installed a FASS Titanium fuel pump,

 and made other mods while he was "under the hood" so to speak.]

Oh, and yes, that is about right for the work to be done.

UPDATE: Our MH is in the shop now having the 20 yr old lift pump replaced. I was going to have  the pump repaired, however the labor involved is the same either way(plus rebuilt labor N parts) so I'm having a new pump installed and be done with it for the rest of my driving life.

[manholt]

However, very cheap to do as Brett said & you might save $3k+

[jleamont]

Speck, what engine do you have, ISB or ISC? One runs the lift pump nonstop the other doesn’t. 

Not to beat this but as Brett mentioned start with filters. Those could certainly cause low fuel pressure fault codes. 

[speck]

On 11/26/2019 at 9:25 AM, wolfe10 said:

Link to Dave's part of the Diesel RV Club Forum: http://forum.dieselrvclub.org/index.php/board,100.0.html

Thanks

On 11/26/2019 at 6:25 PM, jleamont said:

Speck, what engine do you have, ISB or ISC? One runs the lift pump nonstop the other doesn’t. 

Not to beat this but as Brett mentioned start with filters. Those could certainly cause low fuel pressure fault codes. 

I think it is a ISB, but not sure.  Thanks

[wolfe10]

Speck,

Recheck-- I suspect in a 1998 with 330 HP it will be the C engine.

For best answers, post your engine serial number.