Cooling overhaul/maintenance on Cummins QSB 380

[Rankco]

​Looking at (2) 2005 390 Sundancer with Cummins. Narrowed it down to two boats. The deciding factor is maintenance work (which is in the price???)
For peace of mind and to allow me the pleasure of boating enjoying my Margaritas I must have the engines in top condition. We know cooling diesels is a big issue and overheating them will cause you a world of grief and kill the longevity of your engine(s). So questions for those who have been there, done that.

I may do some work myself as I am very good with gas engines, but never worked on diesels. I would send parts out to shop for cleaning, rebuilding etc. Or should I buck up and let a mechanic earn his keep.?
Looking at heat exchanger, aftercoolers, oil coolers. Anyone with costs by mechanic or done themselves?
Thinking of replacing raw water pumps at same time. Sherwoods have bad rep. Anyone used SMX pumps? nervous of what I may be getting into cost wise? Better to rebuild parts or just order new ones. I guess depending on damage.
Do you have to prime raw water system after, oil cooler etc? hoses?
Any tips from those whom have done a complete system overhaul. Anything to worry about fresh water system, thermostats, circulating pumps
I want it all to be perfect. Boat has over 500 hours used in both fresh and salt. Owner says nothing done but wasn't needed? Other boat 600 hours but all cooling maintenance was performed at a cost around $6500 sound right?

 

[marinegasoil]

cummins has maintenance schedules in their owners manuals. per running hours and chronological. if you send in engine serial, will be happy to look up schedule of events.
send the seawater pumps to depco in st. pete. you think someone can start up a pump company and show sherwood how its done? don't be a groupie. depco will make the pumps good as new for pennies on the dollar and you are within engine makers standards. do all the coolers at once and mark the date and hours. that way you have a known document you can refer to. use cummins compleat coolant and Valvoline premium blue. start with all new zincs. if you can swing the shipping, treasure coast radiator in stuart, does marine coolers. they will be cleaned, pressure tested and documented. if they have not been apart since new you might want some help. its easy to tear the aluminum housings up when the cores are stuck. use all cummins parts and filters. that's what your boat was born with. don't forget the gear coolers and the generator. while the coolers are off, it will be easier to access the couplings and check and adjust the alignment. check the mount that's under the seawater pump. sometimes the pumps drip and no one pays attention to it, rusting the jacking stud on the mount. great boat, generator and engines.