Why must my motor warm up first?

[mauzy]

I have a 1981 75 hp evinrude. Motor will not start without choke. Motor RPMs go up 3000 plus then back down and motor will shut off if I don’t re choke. I do this three or four times before motor will idle and warm up so that the motor will not bog down and die when I put it in gear and power up. If I adjust the idle lever during start up the RPMs go up high forcing me to put the idle lever back down. After warm up motor runs good. Start idle and run. After warm up motor idles at 1500 rpm and idle lever will adjust rpms smoothly. Why must I warm up first?

 

[oldboat1]

Re: Why must my motor warm up first?

believe that motor should idle at about half the rpms you indicate (techs here can speak to that better than me). I would say your idle adjustment screw needs to be backed off a bit. If fast idle during warmup was maybe 1000 rpms, and normal idle about 750, you could probably live better with it (and the motor as well).

 

[Capn Mike]

Re: Why must my motor warm up first?

Aw,jeez; is this post for real? Sounds pretty normal to me. Don't you warm up your car engine so it'll run normally? How about any other internal combustion engine? Don't they take a while to warm up? Every engine needs a choke...some are automatic, some aren't.<br />Your motor is 22 years old, which in boat years is, oh say, 66 in human years. Try sprinting out of bed when you're 66.

 

[mauzy]

Re: Why must my motor warm up first?

Thanks for the in put I am new to boating and two cycle motors. It takes about three min to warm up and if the ramp is full that can be aggravating. Maybe I need a newer motor. I don’t see other boats having this problem.

 

[oldboat1]

Re: Why must my motor warm up first?

Well, I think Capn Mike is right about old engines and people taking a little longer to warm up. I would advise, though, that neither outboards or people last very long if you run the bejeebers out of them while they are trying to warm up. Watch those rpms.<br /><br />So let's see, I have a couple of excellent running '57 Evinrudes -- hope I can expect the same at, say, 135 yrs old (?)

 

[martyscher]

Re: Why must my motor warm up first?

Outboard experts!<br /><br />If skydive's "choke" is activated by pressing the starter key, is it in fact just a "primer" that is momentarily adding extra fuel?<br /><br />If so, after starting, would you have to keep pressing the key a bit, until the motor warms some.<br /><br />This seem similar to the setup I have on my 2001 Johnson.<br /><br />Thanks

 

[oldboat1]

Re: Why must my motor warm up first?

Actually, that is essentially all the choke does -- and holding the key in will provide full choke until you let up. Momentary switches are spring loaded, but holding them in keeps the electrical circuit (and the butterfly valve) closed. On my Evinrude, I have preferred to use the manual choke because I like the control. <br /><br />If you trailer, you might try starting the engine with a flusher and running it for a bit in the driveway before you leave. Assuming you don't have to drive halfway across the state to launch, the motor should then be ready to run and idle immediately.

 

[G DANE]

Re: Why must my motor warm up first?

This problem can occurr too if the iddle mixture is a little to lean. Try to run carbcleaner thought the carbjets and see if it improoves.<br /><br />Did you clean the old fuel out and drain bowls before storing for winther ? Old fuel can clock the iddle jets up so iddle mixture gets lean.<br /><br />Engine wount run when cold then.

 

[mauzy]

Re: Why must my motor warm up first?

I have hade the boat for about 5 months now and it has always started that way. No I have not cleaned the carb. It has fresh gas 50:1. If the key is a primer then is there an automatic choke? There are three carbs and I don’t no how to adjust or clean them.

 

[csmithrc]

Re: Why must my motor warm up first?

Skydive i have a 77 Evinrude 140 hp engine and it acts the same way.I just do as oldboat said and usually start and warm up before going out.I only live about 15 min from lake.I rebuilt both carbs last summer (no better).After warmup though she runs great.And Capn Mike there are no stupid questions though some answers are.

 

[MGuckin]

Re: Why must my motor warm up first?

skydive,<br />What you are describing is a normal start up for a many outboards. Rudes do not have an automatic choke. Pushing the key in actvates a selenoid that injects fuel in a way similar to spraying starting fluid into a carb on a car. There is a choke but it fully manual and normally used only for manual starting. Turn the key on and push it in for an 8 count than try to start. When it fires, you may have to keep pushng the key in until sufficient crankcase pressure has built up for the fuel pump to take over. If you are concerned about warm up time at a ramp, consider powering out with a trolling motor, kicker or a paddle but most real boaters are not that impatient and I would think it foolish for somebody to run a motor cold. *hit, what's 5 minutes. I hate waiting at a ramp for someone to rig a boat, but if they have a starting or other mechanical problem, I offer to help. I would not want to be responsible for intimadating someone into a launch they were not ready for. As far as stupid questions: The only stupid questions that I am aware of are the ones that are never asked.<br />Mike<br />

 

[mauzy]

Re: Why must my motor warm up first?