Simple questions regarding old Mercury outboard.

[sycostang67]

I recently picked up a 1974 16' tri-hull Glaspar from my brother in law. I has a 1970-73 Merc 1150 outboard on it, not original to this boat. It was used on a regular basis until the owner passed and it sat for 6 years. I'm no stranger to wrenching, but this is my first boat and 2 stroke motor. The boat was left with a full tank of stabil treated fuel and the motor was run dry of fuel at the end of every outing. So far I have verified the gauges work, the motor has spark and turns over just fine. I have drained all the old fuel from the tank as well. All the wiring in the motor is falling apart however, insulation is cracked and brittle and wire underneath is green. I'm debating whether to take it to a shop to get rewired or attempt to make my own harness.

1. Am I correct in thinking that being a 2 stroke, this motor has no crankcase oil and is fueled and lubricated by what ever is in the fuel tank?

2. What all should I do before attempting to fire this motor?

 

[racerone]

Correct , there is no crankcase sump.----Replace the water pump impeller before launching the boat.----Lucky you if you can find , afford a shop to replace damaged wiring.----You may have to do this yourself.

 

[GA_Boater]

Your Merc uses pre-mix fuel, meaning you mix it at a 50:1 gas to oil ratio.

What's the serial number. CDI makes replacement harnesses and a serial number narrows down which one you need.

 

[sycostang67]

A replacement harness would make things easier, the serial number is #3528113. I actually need both ends of the harness, the cables going to the battery have no insulation left on them either. Is there a "Best" place to find CDI parts and other goodies such as the impeller?

 

[GA_Boater]

iBoats sells all the parts.

The CDI motor harness is 414-2770.

The CDI boat side harness, to the remote control with battery leads, is 474-9550

The OEM impeller is Quicksilver 47-89984t 4 and the aftermarket impeller from Sierra is 18-3017.

 

[Chris1956]

Engine wiring harnesses are found in several places on the web. They are about $100, and easy to replace. Look for the best price.

Boat wiring is more difficult to find and more expensive. I would splice in new battery cables and try to reuse the boat harness.

 

[jimmbo]

Before you go spending money on a 44 yr old engine, do a compression test.

 

[sycostang67]

Engine wiring harnesses are found in several places on the web. They are about $100, and easy to replace. Look for the best price.

Boat wiring is more difficult to find and more expensive. I would splice in new battery cables and try to reuse the boat harness.

It's more than just the battery cables, EVERY wire on the engine side of the harness is falling apart and the battery cables on the boat side are just as bad up to the plug.

Compression test is a good idea, I'll do that this weekend before spending any money.

 

[Chris1956]

Yes, I would expect every wire in the engine harness is bad. Hence my advice to replace it. The battery cables are part of the boat harness. The boat harness is usually in better shape than the engine harness, hence my advice to try to replace the battery cables and reuse the boat harness.

Carefully check the boat harness side of the quick disconnect. Wires do break at that point.;