Official Cummins QSC-500 Thread

You can hear it when the engine switch is turned to the 'on' position. Not sure it is actually a lift pump but it is more like an electric boost pump. Semantics.
QSM's don't have a primer or lift pump. The only pump is the gear driven common rail rail low pressure injection pump down stream of the filter. Manually filling the filters is about the only reasonable way other than continuous cranking for minutes. The filter holds a lot of fuel.
 
QSM's don't have a primer or lift pump. The only pump is the gear driven common rail rail low pressure injection pump down stream of the filter. Manually filling the filters is about the only reasonable way other than continuous cranking for minutes. The filter holds a lot of fuel.

Officially it's called the "Fuel Transfer Pump", but in the remarks for the actual pump part they call it a lift pump. Link below to diagram, note you need to register on quick serve to see it.

https://quickserve.cummins.com/qs3/...ail.html?path=/qs3/parts/87/z/06.05/fs9787-03

What amazes me is how different the models are optioned, this transfer pump is listed as an accessory, but not an upfit part.

I liked having the "transfer/lift/primer/insert your name here" pump. I do wish there was a way to run it on demand, without having to ignition on and off.
 
Officially it's called the "Fuel Transfer Pump", but in the remarks for the actual pump part they call it a lift pump. Link below to diagram, note you need to register on quick serve to see it.

https://quickserve.cummins.com/qs3/...ail.html?path=/qs3/parts/87/z/06.05/fs9787-03

What amazes me is how different the models are optioned, this transfer pump is listed as an accessory, but not an upfit part.

I liked having the "transfer/lift/primer/insert your name here" pump. I do wish there was a way to run it on demand, without having to ignition on and off.
The marinized QSM's were not optioned nor upfitted with one - at least the 52DB's with the Cummins weren't.
The only fuel pump is the mechanically driven injection pump.
I have a funnel that has an integrated filter/water separator that I use to fill the Fleetguard engine fuel filter. I think it is called "Mr Funnel" but could be wrong.... I've had it for a long time...
 
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The marinized QSM's were not optioned nor upfitted with one - at least the 52DB's with the Cummins weren't.
The only fuel pump is the mechanically driven injection pump.
I have a funnel that has an integrated filter/water separator that I use to fill the Fleetguard engine fuel filter. I think it is called "Mr Funnel" but could be wrong.... I've had it for a long time...
Mine has them. Replaced the the port one.
 
Consider Fleetguard ES Compleat.
Your coolant filter should supplement the coolant with the appropriate SCA so you don't need any further supplement in the coolant.
What color is it sir, just wanting to top off.
 
after looking at SBmar I have decided to change over to CAT ELC as Toney recommended. Have use it in equipment for a long time. So going red.
 
The after-coolers are part of the raw water cooling side. Cummins recommends servicing them every 3 years. Make sure you have a Cummins tech on board for when you survey this or any other Cummins powered boat you look at. They are great engines and it is money well spent.
This is what I added to my strainers after spending $15K to service my boat after purchase. The entire raw water side was gone through, after coolers replaced. When I know my boat will sit more than a couple of days, I flush them, ONE AT A TIME, sea cocks OPEN as per Tony Athens. This process flushes the engines with about 80 - 85% fresh water. I am hoping and expecting this might extend after cooler service by 1-2 years. Impellers will be done every 2 years, I only put on 50 - 60 hrs per year. My wide open temps are at 176-179 degrees. The day the temps start to creep up, I will service the raw water side again. ALSO!!!! This is how I get 6 gallons of antifreeze into each engine in the fall. Sea cocks closed of course for winterization. This set up stays on year round.
 

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Have the same issue as OCGrant with the fuel line leaking. It is just dripping now but will get worse I am sure.

We take possession on the 20th and am having this done. Thank you OCGrant for showing the other parts for this job. I am not confident the shop ordered the bracket and the screws...

I sent them a note. I can bet they don't like customers finding out they need to look further than just ordering the fuel line.

Cheers,

Bruce
 
This is what I added to my strainers after spending $15K to service my boat after purchase. The entire raw water side was gone through, after coolers replaced. When I know my boat will sit more than a couple of days, I flush them, ONE AT A TIME, sea cocks OPEN as per Tony Athens. This process flushes the engines with about 80 - 85% fresh water. I am hoping and expecting this might extend after cooler service by 1-2 years. Impellers will be done every 2 years, I only put on 50 - 60 hrs per year. My wide open temps are at 176-179 degrees. The day the temps start to creep up, I will service the raw water side again. ALSO!!!! This is how I get 6 gallons of antifreeze into each engine in the fall. Sea cocks closed of course for winterization. This set up stays on year round.

I like your set up Mark. I was considering doing the same thing to my strainers, when my attempt to find Perkos flushing strainer caps for my engines strainers failed.

How did you adapt the brass nipples to your caps? I don't see a nut and gasket on the nipples, so I assume you drilled and tapped the cap. My drill and tap kit doesn't go anywhere close to that size.
 
This is what I added to my strainers after spending $15K to service my boat after purchase. The entire raw water side was gone through, after coolers replaced. When I know my boat will sit more than a couple of days, I flush them, ONE AT A TIME, sea cocks OPEN as per Tony Athens. This process flushes the engines with about 80 - 85% fresh water. I am hoping and expecting this might extend after cooler service by 1-2 years. Impellers will be done every 2 years, I only put on 50 - 60 hrs per year. My wide open temps are at 176-179 degrees. The day the temps start to creep up, I will service the raw water side again. ALSO!!!! This is how I get 6 gallons of antifreeze into each engine in the fall. Sea cocks closed of course for winterization. This set up stays on year round.
Cool set up.

So, maybe a dumb question, related to passing fresh water or antifreeze through a stationary impeller. Given how an impeller works, it seems it would be difficult to force fluid past it.

Do you run the engines to pull the freshwater or antifreeze through, or can it be forced through the impeller housing when not rotating?
 

Just hung up with Seaboard.... they don't sell flush caps for Perko strainers. They offered to have me send mine to them and they would drill, tap, supply, screw in and solder a 3/4" nipple and supply a ball valve for each cap at $260.00 per.

He was nice enough to send me a link for a tap with the correct thread, so I've just added one more thing to my to do list!
 
Just hung up with Seaboard.... they don't sell flush caps for Perko strainers. They offered to have me send mine to them and they would drill, tap, supply, screw in and solder a 3/4" nipple and supply a ball valve for each cap at $260.00 per.

He was nice enough to send me a link for a tap with the correct thread, so I've just added one more thing to my to do list!
Apologies
I missed the perko.

May I ask you to please post the link for the tap? Thank you Capt!
 
I like your set up Mark. I was considering doing the same thing to my strainers, when my attempt to find Perkos flushing strainer caps for my engines strainers failed.

How did you adapt the brass nipples to your caps? I don't see a nut and gasket on the nipples, so I assume you drilled and tapped the cap. My drill and tap kit doesn't go anywhere close to that size.
I did drill and tap on to the cap. I bought a new set of caps and kept the old ones as spares. It works like a charm.
 
Cool set up.

So, maybe a dumb question, related to passing fresh water or antifreeze through a stationary impeller. Given how an impeller works, it seems it would be difficult to force fluid past it.

Do you run the engines to pull the freshwater or antifreeze through, or can it be forced through the impeller housing when not rotating?
It’s not a dumb question. I run one engine at a time at idle, seacock is OPEN. The result is flushing with about 80-90% fresh water circulating. That is to flush after use. When winterizing, there is a five gallon bucket hooked up filled with non-tox anti freeze and the seacock is closed. I use a total of 6 gallons per engine.
I have also made a single smaller strainer cap for the purpose of winterization of the generator and A/C. All gravity fed, close the sea cocks on both, start the generator and draw in 2 gallons of non-tox antifreeze, and then move it to the A/C strainer, run it until it takes in 3 gallons of antifreeze which is when I see red at the discharge ports. Easy peezy, and never a drop of antifreeze is spilled.
 
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Anyone replace the front crank seal? My mechanic stopped by to take a peak at my motors and told me this year when I change oil to replace my crank seals as they have a small drip and it is common QSC's. I want to figure out how it is done so I can order any special tools and learn to do it myself.
 

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