Cummins QSB5.9 salt water system

[byron]

Hello,

I had an offer accepted in a 2007 Mainship 34. It has a Cummins QSB5.9 with 900 hours.

The mechanic that did the survey has said the salt water system needs servicing, heat exchanger, intercooler, oil cooler etc.

He is suggesting this will take him around 18 hours. Wooza.

Is that correct? Does anyone have experience doing this and the time required ?

Thank you.

 

[dvarholy]

18 hours sounds like an awful lot. The term "servicing" sounds vague. Properly servicing the salt water cooling system would also involve inspecting or replacing all of the hoses from the hull valve all the way to the transom. Also, the raw water pump and impeller would be inspected along with various o-rings and gaskets. I write the month/year any hose, pump, or engine part was replaced. Lastly, new anodes all around. If the hoses are all original from 2007 and need changing, the hours could indeed rack up.

Daniel

'89 Tradewinds 43' MY

 

[O C Diver]

When I bought my boat it had the larger "C" series Cummins engine with intercooler, fuel cooler, transmission cooler, and heat exchanger. I can see 18 hours in removing those items, taking them to the shop, cleaning and /or rebuilding them, and then reinstalling. Add anodes, atleast a new pump impeller, and maybe hoses. Generally you are also paying for transportation time and shop labor.

As an aside, I would consider replacing the transmission cooler if it hasn't already been done, instead of cleaning it. Most don't have anodes and the cost of failure can include transmission work or replacement.

Normally, when I service the raw water side, I service the cooling system as well (you're going to be replacing the antifreeze anyway). Normally that would include thermostat, radiator cap, inspection of the hoses and coolant pump.

Ted

 

[DDW]

I would just have the raw water pump replaced by the SBMar version. Removing the heat exchanger and intercooler are less than 1 hour each, another hour each to put them back on. A shop will likely do the cleaning. Don't know about the transmission cooler, haven't had that off but it also looks like about an hour also. Raw water pump R&R is less than an hour. I guestimate the job at <8 hours, + shop charge to clean cores, + raw water pump. As always, if something goes wrong (bolts break off, bad cores found, etc) then it could be more - maybe that is what your mechanic is contemplating.

 

[Comodave]

Check out sbmar.com as mentioned above. Tony Athens is the Cummins guru. His website has a lot of good info. We have 6CTAs in our boat. Your aftercoolers are probably in need of servicing. Ours are 25 years old but always in freshwater. I tried getting the cores out of the housings without success. I finally bought a new aftercooler for one engine, $5,000. I put it on and took the old one to a machine shop to press the core out. It took 13 toms of pressure to get the core out because it had never been serviced. There are videos on the website on how to service them. Agree on the SMX water pumps. We changed the Sherwood crappy water pumps last year to the SMX pumps. I am changing the transmission oil coolers this winter because I have no idea of the condition of the original ones, no anodes. I got new oil coolers from sbmar that have 2 anodes in them.