1975 Mercury 850 Carb Adjustment

Island_oki2000

Petty Officer 3rd Class
Joined
Aug 31, 2009
Messages
79
First off, everyone one in here providing advice has been excellent. Just ned to make some final adjustments and I think I'm there.

Today I went out with my boat, I've posted about rebuilding the carbs, adjusting the floats after they were not seating the needle correctly and finally got it all back together with no leaks and it idleing.

After starting it up I let it warm up a little then tried to take off. As I shifted slowly into gear, it stalled. It was hard getting ti restarted but it finally did. I let it warm up a little more and then shifted a little faster into gear. It stayed running and ran very strong.

I'm thinking I have the idle set too low and that is why it stalls when shifting into gear slowly. Can anyone confirm? If so, then I guess I have to adjust the idle needles. NEED TO ADD: I started at 1 1/2 turn out after slightly seated for initial seting. As I was adjusting them when I rebuilt the carb, I turned them 1/8 turn at a time counter clockwise and I noticed the idle getting real rough, so I turned them in slowly clockwise unitl the idle smoothed out a bit. I noticed the idle got a little faster and smoother as I turned them in (clockwise).

Is this correct and should I turn them in a little more to speed up the idle?

Thanks,
 

Fuzzytbay

Chief Petty Officer
Joined
Jun 6, 2008
Messages
557
Re: 1975 Mercury 850 Carb Adjustment

Your on the right track. Once you have the idle "tuned" rich up the carbs, by 1/8 turn CCw. Try your hole shot and see how it is, if it falls flat, go another 1/8 turn. These motors like the mixture richer, not leaner.
Heres a link to a thread that should help you out.
http://forums.iboats.com/showthread.php?t=168855
 
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