Mercruiser 3L, Timing, Idle speed, Idle Mixture

[kidafa]

Have a 3L mercruiser manufactured in 2005 thats a Turn Key Start model..... I only recently purchased it 2nd hand and am putting it in the water for the first time in two days.

I plan to check/adjust:

• Timing
• Idle Speed
• Idle Mixture

Is there any thing else "tuning" wise on these engines that I can only set up properly in the water? In what order should I do them? Any tips/advice/how to's?

Reason Im doing this is on the hose it idles fine for first 5-10mins while it warms up and is in high idle mode but then once it returns to normal idle speed it doesnt idle very well (hunts around and stalls) and when you put it into gear it often stalls on the muffs...

Thanks in advance,

Chris

 

[Rocky_Road]

Re: Mercruiser 3L, Timing, Idle speed, Idle Mixture

The correct sequence is:

Timing
Idle mixture
Idle speed

The timing and idle mixture can be done on the 'muffs', but the final idle speed is best done in the water with the engine at full operating temperatures. You may have to up the idle speed slightly while on the muffs to make the mixture setting a little easier. I always do the idle speed last on the muffs, but do the final adjustment in the 'real world'.

Happy boating!

 

[Don S]

Re: Mercruiser 3L, Timing, Idle speed, Idle Mixture

Reason Im doing this is on the hose it idles fine for first 5-10mins while it warms up and is in high idle mode but then once it returns to normal idle speed it doesnt idle very well (hunts around and stalls) and when you put it into gear it often stalls on the muffs...

If you would get the special tool, and adjust the carb like I said in your other post, your problems will likely be gone.

 

[kidafa]

Re: Mercruiser 3L, Timing, Idle speed, Idle Mixture

Yeah Ive got it on order Had a few other questions that I had asked with no response so instead of bumping it and making people read all of it I thought I would start fresh

 

[kidafa]

Re: Mercruiser 3L, Timing, Idle speed, Idle Mixture

Ok so here is a video of my idle....

Boat is tied up in neutral, forward neutral, neutral then shut off. Look ok to you guys?

Had it in the water for the first time yesterday and am very pleased I think the prop thats on it is a top speed prop as it has trouble getting out of the hole a bit and the spedo doesnt work but I just put a tiny screw driver in the pickup on the bottom of the outdrive and it was blocked...