Mercruiser 260 searay 1978

Question

A friend of mine has a 1978 searay with a 5.7 liter 350ci mercruiser 260 that hes tryin to get started. He doesnt have a battery so I used jumper cables with a battery I have to the cables that would connect to the battery ( I didnt have the right terminals on the battery ). I turned the key and all you hear is a click as if the starter is engaging but underpowered to turn the engine over. Allegidly he had it running last summer great. I could use any help to get it started.

Answer 1

Worst case is- it was shut down with bad exhaust manifold. In which case it sat all year full of water. (PS they never run better than with water injected exhaust)- Hope not! on with the story- If you can not  get it to turn over with a wrench and spark plugs removed- squirt some motor oil and STP mixed 50-50 in each spark plug hole--- Now don't everybody scream- but hook 2 12 v batteries together (making 24vt) and directly to the starter. (remove all other wiring to the starter) Get your remote starter and your big wrench on the crank nut and bounce on the wrench(breaker bar) and tap the start button. Something is going to break loose.(I've done this about 7 times and every time it worked and the engine went on to live a normal life.) - Once it is loose -It may not want to start-so keep putting The OIL MIX into the plug holes and squirt some fuel in on top and it will start for a few seconds. Keep going till you can get it to run on a few cylinders. Next go to the yamaha shop for some "ring free". Mix with a 6 gallon can of gas and hook up to your motor. Run it on that till all the cylinders are firing. If the engine sounds good to you- buy the exhaust manifold- install and go buddy boating for a few hours- bring a tow rope. If it still sound good- no smoke spark plugs holding up?- no knocks- your cured.  

Answer 2

ok the battery   get one cheapo

Answer 3

There are adapters made to convert battery terminals to "marine" wing-nut terminals.  Both side mount "GM" and regular bolt on terminals.  Hooking jumper cables probably want get the job done.  Auto parts stores, often carry the adapters.  Next, if the engine was "winterized" it should crank over.  If you can't get the engine to move at all, it helps to remove the spark plugs.  Spray a little oil in each spark plug hole.  In some cases you might need to put a ratchet on the harmonic balancer bolt to give the crank a little help .  Keep track of which wires go where, mark them and be careful!   I hope this helps.. Good luck!

Answer 4

Tell your buddy to pry his wallet out and buy a good quality marine battery.   Make sure the terminals are clean, and start from there.  By the way, if he had it running last summer, where is his battery?