Official Cummins QSC-500 Thread

Does anyone know the raw water capacity of the QSC540? Just curious as I guessed 5 gallons of pink and it seemed that was exactly what I needed.

Also, where is the coolant drain on the block? I need to replace it all.
 
John, Did you have to replace a gasket when you removed the water pumps from the block? What about the SS pipes?

Addendum:
http://www.sbmar.com/seawater-pump-impellers.php
Brad at Seaboard Marine was a big help here. There is a large o-ring on the back of the pump, apparently, that does not need to be replaced. There is an o-ring on the input and output elbows that does need to be replaced. I ordered their SMX impellers which come with a removal tool. They are supposed to be more durable than the Sherwoods and are $120 each, including the tool. I'm going to remove the old impellers as soon at the weather breaks in early April.
 
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Does anyone have the torque specs on the raw water pump bolts (all 13)?
 
I figure there are enough threads about boats, and there are plenty of models of boats with these engines and their variants, so, how about an official thread for the engines?

My SN 46720354 port, 46719228 stbd.
Family 7CEX M0505 AAC
IMO Family M14 QTA
QSC 8.3 500 HO

Impellers: Sherwood 260000K Impellers (K=Kit=includes gasket(s))

Belts: 8-ribbed belts (7 grooves), 1 1/8" wide, 66" outside diameter. About $75 for two from dealer
Dayco Poly Rib Gold Label 5080650 (Also labeled "8PK 6650" - 8 Pack?)

I show the following filters:
Water Sep: 3971757 (Racor 1000MA - Book answer) (900MA in my bilge - 30micron - RA2040PMOR)
Fuel Filter: 3959612 (Cummins Filtration Part #FF5488)
Oil Filter: 3401544 (Cummins Filtration Part #LF9009)
Air Filter: Cummins P/N 3971070 (Element Set# 41-2008) (Air Filter # 41-1030)

Zincs (Boat Zincs dot Com)
E-1 1/2 NPT (E-1Z zinc only) 2" Main (4 per engine)
E-2 3/8 NPT (E-2Z zinc only) 2" Heat exchangers (2 per engine)

OIL: SAE 15W-40 heavy duty engine oil such as Valvoline Premium Blue which meets the following Performance Specs:

(Cummins) CES-20071, CES-20076 API CH-4/SJ, API CH-4
CES-20078 API CI-4/SK, API CI-4
CES-20075 NOT RECOMMENDED API CF-4/SG NOT RECOMMENDED

Racors: 900MA - Engines - 30micron - RA2040PMOR
500MA - Genny - 30 micron - RA2010PMOR

Coolant:
Test Strips: FleetGuard CC 2606B http://www.ryderfleetproducts.com/r...st-Kit-Strips-3-Way-Each/erm/productDetail.do (stolen from another thread)

Engine Test Kits: Engine Models QSC 8.3 500 HO
Order this oil analysis kit: CC2543 – Advanced Testing
Monitor Wharehouse: (931) 526-9551 (order kit there)



I cant find the "E-2 3/8 NPT (E-2Z zinc only) 2" Heat exchangers (2 per engine)" at boatzincs.com is this the same part?
E-1HZ3/8"2"0.063/8-16$2.70



Also how often should I be replacing these?
 
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I cant find the "E-2 3/8 NPT (E-2Z zinc only) 2" Heat exchangers (2 per engine)" at boatzincs.com is this the same part?
E-1HZ3/8"2"0.063/8-16$2.70



Also how often should I be replacing these?
Zincs: Location
Main: E-1Z Engine Zinc Anode (Zinc Only)
Heat Exchangers: E-2Z Engine Zinc Anode (Zinc Only)
See post #57 with the links.

Once a season in salt.
 
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This link may also help you guys........

http://www.sbmar.com/cummins-qsc8.3-tech-info.php


We try and make it easy to find factory specs, besides adding as much info as we can to help owners understand their QSC better.. No fluff, just what we have learned. If something technical comes up and you cannot get a straight answer, drop me a note and I may be able to sort it out for you. I know this engine from the inside out...

Tony ---- tony@sbmar.com
 
Anyone loosing Coolant on 8.3 QSC's ? Bilge is bone dry. HAs to be coming out the exhaust.... Every 10 hrs the expansion tank is bone dry. I can smell the coolant in the cockpit.

Rob
 
Anyone loosing Coolant on 8.3 QSC's ? Bilge is bone dry. HAs to be coming out the exhaust.... Every 10 hrs the expansion tank is bone dry. I can smell the coolant in the cockpit.

Rob
Better to post this on Boatdiesel.com
You can do a search there on this topic. Not much to find. I wasn't seeing this happen until I just changed the coolant. I'm adding to the expansion tank and hope it is from a void in the engine, since I did not have the problem before. I haven't run it enough to say whether I'm losing it or just filling all the nooks and crannies. I can't find a place that does analysis on coolant to see if salt is in it. It already has sodium, so the lab would have to know the baseline, if I could find a lab. I don't like the idea of what could happen if the salt water and coolant are mixing, so I'm going to act fast if I don't see that overflow tank leveling off after the first cruise.

Addendum: I topped it off a few more times and it finally settled down and stopped draining the expansion tank, so my suspicion was correct. I had voids in the engine that were not completely filled with antifreeze.
 
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Is water supposed to gush out when you change the engine zincs??
No, the zincs are all above the waterline. A little will flush out of the coolers, but not much from the heat exchangers if at all.
 
changed the zincs on the starboard side - so what happens now when I start the engines after all that water came out? do I have to do anything different? or be aware of anything?

- First time zinc changer

Sent from my iPad using Tapatalk HD
 
Just check for leaks when you start it but I'm sure it will be fine. The sea water pump will fill the cooling system back up in no time.

Sent from my SM-G900I using Tapatalk
 
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So I am changing the racor filters myself for the first time. I read all the posts I could find and watched a few youtube videos. All went well except when I looked through the glass I saw alot of "black particles" so I emptied all the diesel out of the racor and there is still a fair amount of residual "black particles" on the parts I can see through the glass. So my question is what should I do? just refill with diesel or clean it somehow?

I was also surprised that they were using 10micron.
I purchased and installed the 30micron today.

Sent from my iPad using Tapatalk HD
 
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I believe the spec is a 10 micron for the Racors on QSCs. Blue tops.
 
30 Microns on the Racors is correct. The secondary filter catches the smaller particles.

The black particles are also in mine and pretty common. When you remove the old dirty filters, some of the dirt drops off the filters. Run your boat at WOT for 10-15 min with the new filters in there and see if those particles get trapped in the pleats. I wouldn't worry about them. You don't want to be rebuilding your Racors over this.
 
Q: what exactly is that black stringy stuff in the racors?
 
The black stringy stuff is microbial growth, dead and alive, that has accumulated in your fuel tanks either because you are not treating your fuel or because you got a load of bad fuel from your fuel retailer. Rather than try to re-type the entire thing here, take a look at the CSR home page, about 1/2 way down there are some articles included for your reading pleasure. About the 3rd article down is one about fuel system management that addresses these questions. Be sure to click "Read Mor" on the lower right side of the article on the home page. Near the end of the piece is a procedure for cleaning up a fuel system using readily available fuel additives. If you catch it early enough.......while the boat still runs without slowing down due to clogged filters......you can eliminate the black crud and get on with boating with no worries about getting stuck somewhere.

If you don't react and do something to eliminate the sludge in your tanks, be sure you carry more than one set of spare filters and some diesel fuel in a jug with which to prime the filters because someday when you least expect it, you will have more growing in the tanks than your Racors can handle.
 

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