I currently know very little about outboard engines but am willing to learn in order to keep the service costs down and get a bit more knowledge.
Are these motors any good, and are there any major issues i should be aware of?
Are they easy to work on?
I am also experiencing a couple of problems, and would again appreciate input from someone more knowledgeable.
I've had the motor a couple of years but rarely used it due to a young family,
i don't know its service history but i feel now is the time to bite the bullet and give the engine a good service before i use it a bit more regularly.
I started the engine up yesterday after a 2 year rest and it started first time I know i will need to change the water pump, is this a straight forward job?
I've noticed a small oil leak at the bottom of the gear box it seems to be coming out of the propellor housing, would i be correct in assuming a seal has gone - probably the rubbers going brittle through age!
Also when we last used the boat it developed an intermittent fault and sometimes would not start unless the mercontrol throttle lever was wobbled about. Typically whenever i have tried to trace the fault it has always started but was a tad unreliable on the river last year.
I think this could be down to a sticky/faulty neutral start switch is this a common problem and is it best to change the switch? or is there correct gap required across the contacts to ensure the right operation.
The engine iteself appears to be in reasonable condition for its age although the large rods/bolts the engine sits/swivels on are rusty and would benefit from being replaced - can i still get hold of these?
Lets do one thing at a time. 70's 70hp Mercs were OK in my book. Start by doing a simple impeller change, and thats a must. Look here and see if you can get an idea of a year http://www.oldmercs.com/siteguide.html
Just Google search for a Merc manual...something like
Mercury Outboard 70 HP Manual..
I picked up the impellor and a manual yesterday
started to drop the lower unit today, put the engine in forward gear
and removed 4bolts so far, the bolt either side of the lower unit, the one holding the trim tab on and the other one on the underneath pointing up.
The lower unit has dropped about 6mm but doesn't seem to want to go any further, have i missed anything.
I assume the shifter just couples itself and does not need anything unbolting.