Need help with 4.3L V6 Volvo in runabout
I took my 2004 Regal 1800LSR in for skeg repair about 3 weeks ago. The shop was to: (1) weld on new skeg (2) replace original impeller (3) replace a leaking water circulation pump gasket. Also, the original impeller was completely in-tact when removed. I ran the boat the day after I got it back and it overheated for the 1st time ever. I immediately took it back to the shop. He said I must have sucked up some gunk, so he cleaned it out and gave it back to me the next day. Again, I ran the boat and it overheated.
Fed up with Shop "A", I decided to take it to Shop “B” b/c I no longer trust the 1st place. Shop "B" has since replaced the thermostat - didn’t fix it. They pulled the lower end off and inspected the hoses near the intake to ensure they’re connected correctly – didn’t fix anything. They pulled the impeller shop “A” installed and put in a “more robust” impeller – didn’t fix it.
Today, they will take it back out on the water and run it to get it up to temp and then use a laser temp gun to measure the actual temp of the engine because they’re questioning if the temperature sending unit is bad. They’ve admitted they’re baffled by this overheating condition.
Symptoms: cools OK while idling and at WOT, but nowhere in between. For example, it overheats at planning speed.
Please help me guys! What the heck is wrong with this motor? It was not overheating when I originally took it to Shop “A”.