kssmallies
Cadet
- Joined
- Aug 31, 2007
- Messages
- 8
Hi, I purchased a new boat with a Mercury 500 50 hp motor. On the old motor registration paper it says 1971 but the local boat mechanic says it is a 1967 anyways I changed the lower unit oil it drained for about 2 days. I bought 1 quart of lower unit oil and when I changed it I squeezed from the bottom until it came out the top vent hole like it said to do. When I put the plugs back I noticed I barely used any of the new oil, I still had over 3/4 of the quart left. Is that normal or should I have used at least half of the quart? I also have a problem with going fast the boat goes like maybe 5 mph and thats it. When I throttle down the motor revs way up but I stay the same speed it dosn't go any faster and when I put it in reverse the prop spins but the boat barely moves back? Also when should I change the spark plugs? like every 2-3 months or like every 6 months? and is there any other maintence I can do to keep the motor going good ( change any other oils or grease anything, plugs or fittings to change) any thing like that? THanks any suggestions would help a ton.
So long as you had the motor trimmed all the way down and it came out of the level check hole it should be enough. Spark plugs I do every 6 months or at least once a year, depending how much boating you do, get yourself some good quality marine grease do all your throttle linkages on your powerhead, tilt mechanism etc, get yourself a grease gun for all the grease nipples on the complete unit steering pivot etc. On a motor of that age you'll probably find especially if its been sitting around that the carbie needs a clean and tune up (I would anyway) and I'd also be inclined to unbolt the cylinder head and replace the head gasket and scrub some of the carbon off the top of the pistons while I was there. Should come up sweet ENJOY!!!