The water pump upgrade is a beefed up unit available from Seaboard Marine that is still a direct swap. Pretty easy job overall since Cummins has smartly located the water pump on the QSB engines to an easily accessed location on the top of the engine. The new pump came with a spare impeller for future use and the old pump went into the spare parts bin for emergency use.
The aftercooler came off next. Since it just has raw water cooling going through it the drainage was pretty straightforward. I did have to remove a few extra parts like the air intake filter to get full access to the bottom bolts but it actually came off rather easily. Then it was time to drain all 6.5 gallons of coolant from the engine to remove the heat exchanger. These were both brought home for further disassembly, inspection, and cleaning.
Overall, I was really happy with the condition of both units when disassembled. There were no maintenance records showing they had been apart previously so I was a bit concerned. The heat exchanger was straight forward - just remove the end caps and gaskets. A couple tubes were partially clogged right where the zincs sit and disintegrate. It was taken to a radiator shop and cleaned. Then brought home and pressure tested and repainted. Ready for reinstall.
The aftercooler core removal required a little persuasion with PB Blaster to lubricate the ends and then some gentle tapping with a hammer and block of wood. Once out it was amazingly clean which was a relief after reading stories of them coming out covered in a slimy oily residue. I had ordered an aftercooler rebuild kit from Seaboard Marine and followed their instructions with using liberal amounts of grease on the mating surfaces and O ring when reassembling. It all went together with ease and hopefully following those instructions will make disassembly in the future much easier. That grease also reduces the chance of corrosion between different metal surfaces. Unit was then pressure tested and found to be leak free.
With both units now serviced they were reinstalled and the entire system pressure tested prior to refilling with coolant. I used an Airlift system for pressure testing as well as refilling coolant and was really pleased with how well it worked. Also pleased with the relative ease of reinstalling both components. A little touch up paint here and there and it looks like a new engine. Started right up.
On to the fluid changes. After letting the engine run a bit to warm the oil all 4 gallons were drained using a 9.6 qt vaccum pump system I had just bought on sale at West Marine for $55. Worked amazingly well. 20 pumps - suck out 4 qts, dump it out and repeat 3 mote times! On went a new Fleetguard filter along with 4 gallons of fresh Valvoline Premium Blue 15W40. The transmission is a ZF 85A series that takes plain old ATF fluid. So out came 5.8 qts of the old stuff along with the filter and in went new fluid and a filter. Again, good access to all these drain ports and filters makes the service work pretty easy.
With the engine all set it was time to move onto the generator. We have a Kohler 8.5kw unit referred to as the 9EOZD with around 615 hours on the meter. It utilizes a Yanmar 3TNV76 3 cylinder engine. Just 3 quarts of oil and a spin on oil filter made for a quick and easy job. Replaced the air filter while I had the sound shields off.
I'll get the fuel filters changed before we head off and hopefully that should suffice for the first leg of our journey up the east coast before another fluid change is needed.
