Starting Instructions Mercury 7.5 '77

[steam_mill]

I'm stuck. I've had starting issues with this motor since I got it. Would not start at start of season. Took it to the dealer. Suggested a carb re-build.<br /><br />He charged me 30 minutes labour. Checked spark and carb. Adjusted choke. Assured me that the only thing wrong was the choke needed an adjustment.<br /><br />Engine cold, warm or hot idles great once started, WOT with no problems.<br /><br />I JUST DON'T KNOW HOW TO START IT WHEN COLD OR WARM. STARTS WITH A QUARTER PULL WHEN HOT(WITHIN 15 minutes of running).<br /><br />Questions:<br /><br />Choke seems to have two positions: All the way out and in about 3/8 of an inch. Comments?<br /><br />COLD STARTING:<br /><br />Pump bulb 'til hard(about 7 times)(new pump and fuel line). Pull choke all the way out. Throttle at start position. Pull cord. Second pull, motor coughs and almost starts. Push choke all the way in, motor starts up.<br /><br />WARM STARTING (between 15 minutes of running and 1 hour)<br /><br />Pull cord maybe 15 times with choke (sometimes without)and throttle at start. No sign of life. Get really upset. Pull choke again and keep trying. Will fire up eventually. <br /><br />HOT STARTING<br />Up to 15 minutes of motor running. Pull cord 1/4 turn, motor fires right up regardless of throttle position.<br /><br />I have great spark, fuel is fresh. Motor runs great once started. Tech says everything is running right.<br /><br />I figure I'm the problem.<br /><br />Comments?<br /><br />Thanks!

 

[sloopy]

Re: Starting Instructions Mercury 7.5 '77

Don't USE choke when the engine is warm.

 

[Motor Boater Bill]

Re: Starting Instructions Mercury 7.5 '77

Visually check to make sure the choke is closing all the way when you operate the choke lever. Also, with the motor in neutral, open the throttle as far as possible. There should be a stop that prevents you opening it all the way. This should be the start position for the throttle and may or may not line up with the marks on the handle.

 

[steam_mill]

Re: Starting Instructions Mercury 7.5 '77

Should the choke flap completely cover the carb opening? I have clymer manual but nothing on where the choke flap should be.<br /><br />Also, I've always pumped 'till hard. Should I pump less?<br /><br />Motor Boater Bill: <br /><br />The start actually lines up with the stop and the throttle is as open as can be with the motor in neutral.<br /><br />What are the symptoms of a flooded motor?

 

[dajohnson53]

Re: Starting Instructions Mercury 7.5 '77

Originally posted by steam_mill:<br /> Should the choke flap completely cover the carb opening? I have clymer manual but nothing on where the choke flap should be.

The choke flap should completely cover the opening when the choke lever is pulled out. I had to adjust the cable connection on mine - the cable that actually operates the choke at the carb. Mine is a 9.8, but probably similar to your 7.5. If yours doesn't cover completly, let me know and I'll find a couple of old posts where people described how to adjust that cable.<br /><br />

Also, I've always pumped 'till hard. Should I pump less?

Unless gas is being forced out of the carb, I don't think you can pump it too hard.<br /><br /><br />

The start actually lines up with the stop and the throttle is as open as can be with the motor in neutral.

You can re-align the label. You move the twist to the start position (as wide open as you can move it in neutral) - don't pay attention to the label. Then, disconnect the tiller arm at the joint and while it's disconnected, move the twist grip to the correct position - so the "start" label is at the little pointer - and then reconnect the arm. My OEM merc manual describes how to do this, I don't know if the clymer does. Another way to deal with it is to have a decal shop make a copy of the little label and replace it, but with the start/shift, etc. labels in the correct position.