Join Date: Sep 2016
Year/Make/Model: VN 1500 Classic
Coolant not draining?
I know that there have been similar posts to this as I have just read one from 2012. Unfortunately, there was no satisfactory conclusion as regards the cause. I have changed the coolant on my 1998 Classic today, the first time since I have owned it. I followed the usual instructions, removing the speedometer housing and the radiator filler cap. When I removed the coolant drain plug from the bottom right of the engine case, the coolant did not drain. I checked to see if the drain was blocked, but it wasn't. I was able to insert my small screwdriver through the drain into the engine case at least 4'', but it appeared to be dry. I finally removed the hose from the bottom of the radiator where it connects to the pump. It drained and I collected 1.8 liters of old coolant. The capacity of the system I think is 2.4 liters, which means that I had only drained the coolant from the radiator and not the engine. I replaced the hose and re-filled the radiator with distilled water and ran the bike until hot. I then drained it again and the water was slightly green, so it had passed through the engine and removed the old coolant. Again, the amount drained was 1.8 liters, so 600 ml of water remained in the engine.
I then repeated this, filling the radiator with premixed coolant and ran the bike again until hot. I then drained it again and collected 1.8 liters of what appeared to be just pure green coolant. Obviously, as before 600 ml of coolant had remained in the engine. I finally finished by refilling the radiator with coolant. This was a long drawn out way to ensure that ALL the coolant had been fully replaced, I am still very confused by the fact that at no time did any coolant come out of the drain. The bike has always run very well and doesn't overheat and the cooling fan operates normally at the correct temperature. I just can't figure it out but would like to, as today's coolant change took me 4 hours as I had to wait for the bike to cool before each re-fill. Please any ideas?