My VN750 overheated just as I was pulling into the garage after riding home on the first really nice (over 78 degrees) day since I purchased it. '06 with 2k miles. Checked coolant tank and found it was very low. After cooling off it was still low. Topped it off with distilled water.
Rode again next day in similar temps and now was paying close attention to gauge. Needle was running close to middle of the gauge all the way home and would creep up when bike was stopped.
Purchased cheapo antifreeze tester and checked it after bike cooled. Only floated 1 ball out of 5. Time to change coolant!! Went to Wallyword and found out Dexron and SuperTech both have exact same ingredients, so went with SuperTech.
Drained coolant from drain at bottom of engine, bolts under spark plugs on each cylinder and radiator. About 1.5qts total came out, not including the dribble from the cylinder bolts. No oil in used cooant. Refilled radiator & tank with 50/50 mix and burped using bleed valve and also got a some bubbles to clear while revving the engine a little. Tester now floats 4 balls.
Let engine cool and topped off tank (1/4 cup low) and radiator (also 1/4 cup low). Now gauge will read between 1/3 and 3/8 of the way. Seems hot
compared to my wife's which runs a little above the 1st hashmark to the right of stone cold. I can smell coolant around fuel tank area and figure next step is to remove fuel tank and check all clamps for tightness and hoses for cracks/leaks. Coolant tank is a little low after each ride. Pressure cap may need to be replaced too.
Anything I'm missing on the cooling problem?
By the way, radiator fan works.
Decided to change oil too.
Went with Rotella 5w-40 synthetic and SuperTech filter. Totally warmed up engine released exactly 3 liters of of old oil that didn't look totally black yet. Used side drain and let it go for at least an hour while I did other stuff. No water in oil. Replaced drain and dropped off old filter which got me about another cup of oil in the drain pan.
Based on the output (3 L) I thought maybe it was running low even though the sight glass (on center stand) said it was just one RCH below full. Poured in 3 L of new oil. Sight glass indicates full. Started up engine and watched oil disappear from sight glass. Shut down after less than 60 seconds. Sight glass now shows just below full so I added a couple ounces of oil. Sight now glass now shows full with a little bubble at the top or sometimes no bubble. Went for 15 minute ride. Same story with oil level in sight glass afterwards.
Where's my extra liter of oil supposed to go??
On a side note there appears to have been some sort of leakage onto the rear wheel/tire from the gap between the wheel and shaft housing. Not much and it may have been something I drove through, but not sure about that since we've had no rain here. Not riding again until I crack open that assembly and check gear oil level.
What else should I be on the lookout for with such a low mileage bike that probably wasn't ridden much, if at all, in the last few years?