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just picked up my first boat i have a couple questions

H

harobikes1988

New member
hey everyone so i just bought my first boat its a 1984 18 foot smokercraft with a 1983 mercury 70 outboard motor i bought it non running i was told the starter was shot. i replaced the starter and i am going to go buy a new battery for the boat today hopefully if i have time. i still need to put the new waterpump in it but i am wonderingwhat type of gear oil i should use and how many quarts the lower end holds because i want to change the oil in it i have never owned or worked on a boat motor before but i do spend a lot of time working on atv motors and stuff like that so any tips on other things i should do or look for would be greatly appreciated thanks for your time.
 
Use Mercury or Quicksilver high performance gear oil- you'll need about 14 oz of oil, and a pump to get the oil into the gearcase (pump it into the drain hole until it comes out the top, vent hole). You can pick up a little pump that attaches to the oil container at any marine supply store, about 10 bucks. Don't forget to replace the seals on the drain and vent screws, worn seals are the biggest cause of water intrusion. While you're at it, remove the prop and grease the propshaft splines, and grease the tilt tube and pivot shaft.
 
thanks guys i dont have a gauge to test compression unfortunately but this is a hard starting motor from what the guy said. i will def get new seals for the plug and vent screw. is there a certain weight i should use for the gear oil?
 
Definitely do a compression test BEFORE you do anything else, for these triples tend to burn up the top pistons. If that's the case, you'll need a rip down to fix it.

Hope not.

Jeff
 
i was told the motor ran fine besides the starter not working he pull started the motor to get it running ik that this doesnt tell if the rings or other things are bad but the motor and lower unit are spotless and there is no discoloring on the heads or anything but it does look like the motor has never been split the factory paint is not chipped or cracked around the gaskets but i will try to find a compression tester and check the cylinders. i read online that as long as they are above 100 and no more than 5 psi difference that the piston and rings are good does that scenario work for these motors or should the compression be higher sorry for all the questions i just want to make sure i am right because i want this boat to last and i have never messed with a boat motor before.
 
While you're waiting, pull the top plug and look for signs of aluminum flakes on it.

Jeff

PS: My triples (I have several) test out at 135 psi to 150 psi on compression tests.
 
No such thing as a motor that is IN GOOD CONDITION being hard to start.--------No such thing as a " cold blooded " motor either.------------A motor in good condition will start right up if proper procedure is used to start it !!!!
 
so i checked the compression today and all three cylinders were at 135 psi. so i am going to go ahead and replace the water pump i knew about the wear plate and everything so i bought a whole kit and i will replace everything and i also need to replace the lower end oil so should i use 90 weight gear oil for the lower end?
 
..."i checked the compression today and all three cylinders were at 135 psi"

Excellent! Do this as well: On the right side of the power head, in the adapter piece between the block and the tower, is a water line that goes to the fuel pump. Disconnect that fool line and plug it with an 1/8 inch pipe plug. (Why? The impeller is a bit small on these motors, and they need all the cooling water to go through the power head, not the fuel pump. Trust me on this!)

Jeff
 
i cant seem to find the screw that holds the shift linkage together to drop the lower end to replace my waterpump i could only find a rollpin that goes straight through the link is this what i need to remove to be able to drop my lower end
 
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