I have a 1984 Mercruiser 3.0L. I hooked it up to the garden hose today and tried to adjust the idle and mixture screw. It seemed that no matter what I did, it never ran right. once the choke warmed up and the plate was wide open it still was acting like it was getting too much air no matter where the mixture screw was. so if I took my finger and closed the choke plate so that it was only open about 1/4" then the engine idled much smoother.
I then noticed that on my temp gauge it was only reading about 110-120 degrees after about 30 minutes of idling.
Here is where I things might go downhill!!!. I was making some adjustments, and then started the engine. I was making adjustments for about 2-5 minutes and all the sudden the idle smoothed out and seemed just where I wanted it. I then looked at the hose, and there was no water moving through it. The hose has a kink in it on the grass. I jumped down and unkinked it and water started flowing.
I am pretty sure I will need a new impeller, I will need to remove the outdrive to make sure. I did not smell any burning rubber or any odd smells at all really. Right before I noticed there was no water, my temp gauge was saying 175. SO at least the engine did not get too hot.
Here is my question... Once the engine reached 160-170 it ran much better idle and quick flips of the throttle seemed much better and it no longer acted as it was getting to much air and wanted to die. So could my idle issues be caused by the engine never getting above 115 degrees and that was why it was getting too much air and needed the choke plate to be closed.
I will need to take the lower off and look at the impeller (that I just replaced a couple months ago) and see if it did any damage.
Could my 2 month long battle with my idle issue, and removing and cleaning the carb twice all have been caused by the thermostat not letting the engine get above 115 degrees?
I then noticed that on my temp gauge it was only reading about 110-120 degrees after about 30 minutes of idling.
Here is where I things might go downhill!!!. I was making some adjustments, and then started the engine. I was making adjustments for about 2-5 minutes and all the sudden the idle smoothed out and seemed just where I wanted it. I then looked at the hose, and there was no water moving through it. The hose has a kink in it on the grass. I jumped down and unkinked it and water started flowing.
I am pretty sure I will need a new impeller, I will need to remove the outdrive to make sure. I did not smell any burning rubber or any odd smells at all really. Right before I noticed there was no water, my temp gauge was saying 175. SO at least the engine did not get too hot.
Here is my question... Once the engine reached 160-170 it ran much better idle and quick flips of the throttle seemed much better and it no longer acted as it was getting to much air and wanted to die. So could my idle issues be caused by the engine never getting above 115 degrees and that was why it was getting too much air and needed the choke plate to be closed.
I will need to take the lower off and look at the impeller (that I just replaced a couple months ago) and see if it did any damage.
Could my 2 month long battle with my idle issue, and removing and cleaning the carb twice all have been caused by the thermostat not letting the engine get above 115 degrees?
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