I have a 2.0 1984 Mercury 150 that has good compression and operates very well up to 5900 WOT. I never run the motor above 5700, but the power is there if I need it.The problem I have with this motor is the constant need to give the motor throttle when starting the engine. Even if the motor is idling, and I turn it off, then restart, I will need to give it some gas. It is not a big problem, but it is kind of annoying. I used to own a 1979 Evinrude 140, and that motor would fire every time with a bump of the key.At the time that I owned it, I really did not take very good care of it yet it always fired reliably.i know both are good motors, but I am wondering why the mercury is so needy at start up. Is there any fine tuning characteristics that I can check? The tank, fuel lines, bulb, gas line fitting, fuel separator are less than 1 year old. Tune up is 2 years old. Carbs are 3 years.The motor also ran the same way on a different hull. Any advice?

Does the motor idle good once started?

Two stroke motors are like people. They are all a little different. My last Force was the same way. My 95 Johnson hits first lick. For some reason they all seem to have a different sweet spot. I've got a Stihl edger that's cold natured as hell but once warm, it will chew through anything.

I wouldn't worry about it one bit. Just preset your gas for the first start and roll on.

Does the motor idle good once started?

It idles slowly, almost borderline stalling during the summer, a little faster when it is cool. I suppose I could bump up the idle a bit.

Two stroke motors are like people. They are all a little different. My last Force was the same way. My 95 Johnson hits first lick. For some reason they all seem to have a different sweet spot. I've got a Stihl edger that's cold natured as hell but once warm, it will chew through anything.

I wouldn't worry about it one bit. Just preset your gas for the first start and roll on.

I agree with what is said above, if it isnt fully broken dont mess it up.

My earilier question was to try and figure out if something had gotten into the idle jet in your carb which could be causing it not to idle good.  I have only taken apart simple carb (single cylinder dirt bikes and small HP outboards).  Just taking a stab in the dark really, sorry I cant be of more help.

Does the motor idle good once started?

It idles slowly, almost borderline stalling during the summer, a little faster when it is cool. I suppose I could bump up the idle a bit.

You could change the idle screw, but you would have to change all carbs (4 or 2 on that motor?) the same amount.  You can mark them before you try it, that way you can change them back if you screw up.  Or take it to the shop if it bothers you. 

My 1988 48 hp johnson does the same thing, I just drive it with some (full)  throttle and try not to idle around, it can get interesting at crowded ramps.  Mine only seems to die when idling in gear though.  Who knows!

Does the motor idle good once started?

It idles slowly, almost borderline stalling during the summer, a little faster when it is cool. I suppose I could bump up the idle a bit.

You could change the idle screw, but you would have to change all carbs (4 or 2 on that motor?) the same amount. You can mark them before you try it, that way you can change them back if you screw up. Or take it to the shop if it bothers you.

My 1988 48 hp johnson does the same thing, I just drive it with some (full) throttle and try not to idle around, it can get interesting at crowded ramps. Mine only seems to die when idling in gear though. Who knows!

The motor is a 6 cylinder, with 6 carbs. I think the throttle cable can be adjusted to open all the carbs together to increase the idle. I will give that a try.

Does the motor idle good once started?

It idles slowly, almost borderline stalling during the summer, a little faster when it is cool. I suppose I could bump up the idle a bit.

You could change the idle screw, but you would have to change all carbs (4 or 2 on that motor?) the same amount. You can mark them before you try it, that way you can change them back if you screw up. Or take it to the shop if it bothers you.

My 1988 48 hp johnson does the same thing, I just drive it with some (full) throttle and try not to idle around, it can get interesting at crowded ramps. Mine only seems to die when idling in gear though. Who knows!

The motor is a 6 cylinder, with 6 carbs. I think the throttle cable can be adjusted to open all the carbs together to increase the idle. I will give that a try.

Huh? Six carbs? Friend, you better get someone else working on that motor.

Three carbs is what it has.

Those old motors would scream. They love rpms and lots of jetting.

Could be a needle and seat problem or as simple as a vaccum leak in one of the carbs. Only a couple of moving parts to each carb. Check the hoses or if you think they need it tear them down, kit them, reinstall, set the mixture and idle adjustments and you should be good to go. I run one on my Skeeter and it's just hit the key and it's ready to go.

Does the motor idle good once started?

It idles slowly, almost borderline stalling during the summer, a little faster when it is cool. I suppose I could bump up the idle a bit.

My 75hp Optimax does the same thing.  It doesn't like slow idle much at all but runs like a champ when you give it any gas at all.  I'm not going to mess with it

When you have multiple carbs you need to have someone do the work who has the correct tools to check for minute variances inn the RPMs as the carbs are sync'd up.

For example, for a given engine, it may call for turning the idle up for carb number 2 until you get a certain exhaust mixture. Then it may call for turning up the idle by 25 RPMs.

Also, the ambient temperature when the engine was tuned could have something to do with why it runs odd when warm. The engine could have been tuned when it was 55 and low humidity. In addition, the time of year when it was tuned could also have something to do with it since most states have winter and summer blends of fuel based on time of year. I guess what I am trying to say is to have the engine tuned during the approximate temps that you will do most operation.

I would try adding Seafoam to your gas for a few tanks of gas before any mechanical work is started. This seams to be helping the hard starting and idle problems on my 70 hp merc 1988 model .

Does the motor idle good once started?

It idles slowly, almost borderline stalling during the summer, a little faster when it is cool. I suppose I could bump up the idle a bit.

You could change the idle screw, but you would have to change all carbs (4 or 2 on that motor?) the same amount. You can mark them before you try it, that way you can change them back if you screw up. Or take it to the shop if it bothers you.

My 1988 48 hp johnson does the same thing, I just drive it with some (full) throttle and try not to idle around, it can get interesting at crowded ramps. Mine only seems to die when idling in gear though. Who knows!

The motor is a 6 cylinder, with 6 carbs. I think the throttle cable can be adjusted to open all the carbs together to increase the idle. I will give that a try.

Huh? Six carbs? Friend, you better get someone else working on that motor.

Three carbs is what it has.

Those old motors would scream. They love rpms and lots of jetting.

Could be a needle and seat problem or as simple as a vaccum leak in one of the carbs. Only a couple of moving parts to each carb. Check the hoses or if you think they need it tear them down, kit them, reinstall, set the mixture and idle adjustments and you should be good to go. I run one on my Skeeter and it's just hit the key and it's ready to go.

Yea, it has three carbs. I do not know why I typed 6. Each carb has two venturi's. I do some of my own work, but I will usually let a pro do the carb work. If the easier suggestions do not work, then carb rebuild and link n sync is what I will have done..

Mike Z might be on to something. The seasonal temp and pressure changes could be having an effect.

I will put in some seafoam in next time out and see what happens. 

thanks guys