1988 Merc 70hp

[Dick Bacon]

Why is my 1988 70HP so hard to start when cold ? I lift up the lever, push in the key, wait about 10 seconds and crank and crank and crank and repeat several times. In a couple minutes it finally starts and then ok all day. If I am fishing for a while it gets a little stubborn again but not like first thing. It has always done it since I bought it a few years ago. Never left me stranded though, always eventually starts.

I have cleaned carbs and put in new needles, new plugs every spring, new CDI box, new fuel lines and filter. I had it into the shop last year for some work with a broken throttle linkage. The guy said those old Mercs are just cold blooded like that.

 

[roscoe]

Do you squeeze the fuel bulb till firm before attempting to start the engine?

Your engine does not have a conventional choke.
It has a fuel enrichment valve.

When key is pushed in, solenoid opens valve, and extra fuel is released into the manifold.
It only dumps extra fuel while the key is being pushed in.
It uses pressure from the fuel line bulb and fuel pump.

The fuel pump and carb need to be filled with the bulb before pushing or turning the key.

Starting procedure:
Open fuel tank vent

Squeeze fuel primer bulb till firm.

Lift fast idle lever or... advance the throttle 3/4 way, without putting it in gear if your remote control allows this. -- This is done by either pushing a button in the center of the controls, or pulling the shift handle toward the driver, or raising the fast idle lever, all depending on what control unit you have.

Turn the key to the on/run position.

Activate the choke (fuel enrichment valve) by pushing in on the key. The valve is only open while the key is being pushed in.

Turn the key to start while continuing to hold the key in.

Release the key and choke when it starts.

3-5 seconds of "choke", is usually enough.


You should not have to use the choke much, if at all, once the engine has warmed up.

Engine should start within 10 seconds of turning the key.

Good luck, let us know if this makes any improvement.