Pays to check settings

[MickLovin]

Hi guys, after painting the boat, I decided to start the old 100hp up and give her a clean out, she started as usual first start but had to crank a lot more than usual, but it idled and ran fine. I was a bit puzzled why it cranked so many times before starting as it usually starts about 4-5 cranks, so I decided to check my settings. I put it it into forward and noticed the revs were only about 600, thought that was strange and a bit low. so I decided to check my throttle linkage and my carbie shutters to make sure they were horizontal at WOT. For some reason they weren't, I could have sworn I had them horizontal at WOT last check and water test. So I adjusted the throttle linkage so they were horizontal at WOT and tightened pertaining nuts which were tight originally. I think I will now have to adjust idle speed as it would have increased it. My question is,when it is idling out of gear what is it's idling speed?? And when going firstly into gear is it 700-800??
When I set it I have forward at 750, but now I am unsure what out of gear idle should be??
Probably just confusing myself:facepalm:

 

[MickLovin]

Re: Pays to check settings

Also checked my cam, it was still ok as it funny enough lines up with the line as in the line on the cam is in line with the line on the roller when it first touches.

 

[pnwboat]

Re: Pays to check settings

Not every motor is exactly the same, but I set my idle speed to around 900 RPM's in neutral out of the water. When I drop her in the lake (more back pressure on the exhaust), the idle speed is about 850 RPMs in neutral, 750 in gear. I have found that when I set my motor up like this, it seems to behave the best at idle and just above idle speeds.

I use the engine RPMs as a general guideline, but I put more emphasis on how the motor behaves rather than aiming for a specific RPM for my settings.

 

[Frank Acampora]

Re: Pays to check settings

Because idle speed is set in gear, the actual idle in neutral will vary depending upon prop pitch. The higher the prop pitch, the more you need to screw in the idle stop screw to raise the idle to the required 750 RPM. This means that in neutral, the RPM will also be higher. THUS: Neutral RPM can be almost anywhere between , say, 850 to 1000 RPM.

You would only use neutral RPM as a rough guide to setting throttle in the driveway. It has no relation to actual performance on the water.

 

[jpwilly]

Re: Pays to check settings

Is it cold where you are at? I had been running my engine and did the sync and time in my driveway with temps during the day of high 70's here in AZ when I went to the lake for the first time it was just 50 out and the engine acted like I hadn't tuned it at all. Once it warmed up then I was relieved and had to adjust idle in the water. Still started hard and I'm working on that but wondering if the cold blooded nature of the 2stroke has something to do with it cranking so much. Not sure your WOT setting would have effected the startup so much as top speed on the lake.

Note: For us without a working tach on our boats. Set idle in the water with the boat in gear (when all other things are in tune) is correct to adjust overall idle speed. Keeping it as low as possible to prevent wear during shifting.

 

[MickLovin]

Re: Pays to check settings

Ok update time, Firstly it isn't cold here jp, been hanging around 27-30 deg Celsius or 80 - 86 deg Fahrenheit So no it's not the weather, I released the 2 bowls last night and found some white floating crud in there on the bottom bowl, I have set my idle @ 750 rpm in forward and it's around 850 rpm in neutral. I did this last night and it started first time again this morning with a lot less cranking, now waiting for it too cool off to make sure it does the same. Also buying some Seafoam for the carbs and fuel.

 

[MickLovin]

Re: Pays to check settings

Ok I have dropped it down a bit to 700rpm in forward and around 750-800 in neutral, I found it was hitting in a bit hard when it was 850+ in neutral.

 

[Justinde]

Re: Pays to check settings

No offence to the lads here from the U S and A, but...... You COULD have titled the message

It Pays to Cheque the settings;-)