'77 70hp evinrude slow warmup

[breakNrun]

This motor run fine at all speeds after warming up, but it takes about 5-10 minutes before it will settle down. I have to nurse the choke and warm up lever to keep it running during this time. I have replaced plugs, had a professional rebuild the carbs last year, check all the fuel lines and installed a fuel/water filter. Idle is set to 800 and wot is 4700. Any suggestions?

 

[jtexas]

Re: '77 70hp evinrude slow warmup

Takes at least 5 minutes to warm up, use the hi-idle lever to give it as much as it needs during this time, bump the choke once or twice to get it going...sounds about normal.

Does it start and idle good after warming up?

Idle should be 800 with the lower unit submerged...set it to 1000 on the muffs -- backpressure on the exhaust will bring it on down -- then fine tune it at the lake.

You could test the thermostat on the stove in a pot of water with a kitchen thermometer, should open at about 125? F. If you do decide to do that, go ahead and replace the bypass valves, you'll see 'em there under the thermostat cover.

Pump the primer bulb until it's nice & firm.

You could go another 500 at WOT if you wanted to.