Joey Pierce
New member
Hey all, thanks for taking a look at my post. I work on a tug with 4 6-71's for propulsion, 2,600hrs since last overhaul. The engines are keel cooled, with each engine to it's own cooler, coolers aren't shared or connected to each other in anyway. Normal running speed for us is 1,700rpm, never any faster since we never get over 4 knots no matter what. I'm now having to run 3 of the 4 engines without thermostats to keep a mid 180's temp on them at 1,600rpm. On really warm summer days we have to back down to 1,500 to keep from running hot. I've chemically flushed cooling systems and replaced thermostats before finally removing them completely. These engines only have the fresh water pump on the blowers for coolant circulation and have been running fine the last 4 years. I replaced water pumps with no avail. I've re-plumbed the trans coolers out of the engine cooling circuits with no luck. I have a 25* temp differential on my keel cooler in/out, and as soon as we throttle down my temps plummet immediately, so I know my coolers are shedding heat. I've discussed this with a handful of other tugs in my area and we're out of ideas. This issue has developed in the last couple months and I don't have the luxury of being able to shutdown more than one engine at a time for more than a few hours.
I have very limited chances for cell coverage/internet connecting here in Western Alaska, but will try my best to check in often. I'm stumped and appreciate any help.
I have very limited chances for cell coverage/internet connecting here in Western Alaska, but will try my best to check in often. I'm stumped and appreciate any help.