Engine will not idle

[thisuldoit]

I have a 1989 Wellcraft Eclipse XL with a 4.3L Mercruiser engine. It has been sitting for three years. I went to take it out today, and with a little trouble and starting fluid, I was able to get it to start using the throttle only button and giving it full throttle. I would then back off on the throttle and let it run for a little while with the throttle only engaged. When I would try to move the throttle back to the neutral position the engine would die. Is this a switch issue, or a carburetor adjustment issue, or what?

Thanks!

 

[Don S]

Re: Engine will not idle

After sitting for 3 years, the carb is probably all varnished up inside and all the passages plugged.
Time for a carb rebuild and a tuneup.
Better change the raw water pump impeller too.
Who knows what else it needs.

 

[thisuldoit]

Re: Engine will not idle

The previous owners said it was winterized before she left it sitting, but I am sure it needs a carburetor rebuild.

Thanks.

 

[Don S]

Re: Engine will not idle

Winterizing means different things to different people. To some, just draining the cooling system is called winterizing. To others, it also includes, stabilizing the fuel, oil&filter changes, fuel filter changes, gear lube changing, pulling the outdrive and looking for water in the bellows and lubing the gimbal and ujoint bearings, checking the alignment, then fogging the engine.
Which did yours receive?

 

[thisuldoit]

Re: Engine will not idle

Have no idea. It was the previous owner who did it and all she said is that it was winterized. Probably the lesser of the two, as I think she did it herself.

By the way, estimated cost on the rebuild of the carburetor and the replacement of the impeller?

 

[Don S]

Re: Engine will not idle

If you are planning on taking it to a shop for repair, be sure to tell them that you suspect NOTHING has been done to it for 3 years, expect to pay for 4 to 8 hours of labor. Hard to say what all is going to be found or what condition it's in. I could be over, or way under the actual cost. We charge $99 an hour for labor, plus what ever parts are needed.
If you would like to save some money, find the OEM (Mercruiser) service manual for you engine and drive, and study them. Depending on your mechanical skills, you may be able to do some of the work and save yourself a lot of money.
Here is a link to the OEM manual for your drive (Free), sorry, nothing for your engine. But it will sure help you understand how things work and fix it yourself if you study it.

http://www.boatfix.com/merc/Servmanl/6/6covr3.pdf

Another helpful site for repairs is below.

http://www.mercstuff.com/howdoi.htm

 

[thisuldoit]

Re: Engine will not idle

Thank you for the sites. They will help. When you say the raw water impeller, do you mean the impeller in the lower unit of the outdrive? (the small rubber star-shaped object). I have replaced that in a outboard before and it was not too difficult.

 

[Don S]

Re: Engine will not idle

When you say the raw water impeller, do you mean the impeller in the lower unit of the outdrive? (the small rubber star-shaped object). I have replaced that in a outboard before and it was not too difficult.

Yes, that is the raw water pump impeller.
Look at the manual link I gave you.
It's NOT an outboard.