1999 S200 Rpms bounce up and down after idle speed...

[CaptainSteve75]

Just recently bought a boat, came with a 1999 200hp Saltwater series (S200TXRX)...and the dam engine is not working properly...Figure that.

Currently the engine on idle sound like a champ.

When I take off on idle...No problem...nice and smooth.

As soon as I accelerate, it picks up speed for about 2-3 seconds, and then the engine starts to bounce the RPM's up and down.

When I attempt to continue like this...the engines RPMs start to bounce up and down maintaining a speed from 4 to 7 mph max.

Then I have tried to give it full throttle it sound and feels like, it is going to launch us right out of the water for about 2-3 seconds...WOO HOO...then it drops and if kept completely open...it bogs out and feels like it is going to shut off.

So this is what I have done so far to attemp to remedy the problem:

1. Review and clean (Air Compressor) all gas lines from tank to Carbs.

2. Replaced Primer Bulb and Water Separator.

Then ran it again...same thing...maybe a tad bit better.

3. Rebuilt (Yamaha kit) and Clean Carbs (Air Compressor and Carb Solution). Used all specification per Seloc Repair manual, Float Height, Air Mix Screw, etc.

Then ran it again...speed now increased to a whooping 7 to 11 mph, but Rpm, once passed idle speed...starts to bounce up and down again...opening up a little better, but basically the same.

Almost seems like it is jumping in and out of safe mode (Guessing)

Thanks in advance with any suggestion to this matter.

[boats.net]

Run a compression test.
Test warning buzzer to see if working, remove pink wire and black wire from temp sensor on cylinder head and touch to pink wire to black wire, turn key on buzzer should sound.
Could be the ignition breaking down but normally is dirty carbs or restriction in fuel system..

[CaptainSteve75]

Starting from left to right facing back side of motor

1 124
2 95
3 124
4 124
5 124
6 124

Forgot to mention:

Water temp is cool to warm while running

Carburetors look like they have a cold sweat

And also replace both mechanical fuel pumps

I will try the buzzer and let you know.

Thanks again

[jb123]

its apparent you have an issue with the #2 hole, dont run, pull head and look for cylinder scarring

[CaptainSteve75]

Two separate response:

No Scaring in cylinder, manual suggest you can have a 25% - 30% variance on compression...ideally the best thing would be is to repair/ replace to reach optimal running condition.

Alarm looks like it could of been disconnected, not working when wires are connected as mentioned above.

Thanks again...

Anymore suggestion?

[mitch]

It sound like for some reason the fail safe mode in kicking in , low oil sender or temp sender no 2 cly being down is not going to cause that prob.

Because it is a carb model the fuel is still being delivered hence the surge once the spark comes back after the fail safe I not am sure what rpm fail safe starts working at maybe 3000 or 2500.

That warning buzzer not working needs further investigation might be the problem ? has it been disconnected or is it stuffed. test the temp sensors with a ohms meter

Once you have worked out what the problem is you will need to do a reset to clear the memory other wise it will remain in fail safe

[CaptainSteve75]

Thanks guys for countinuing to provide feedback...

Once I find out whether or not the alarm is working...

Would the thermo's be a good idea to change? Considering that maybe causing the intermitten problem.

And if the thermo's were bad, how can I reset the system and take it off this so called "Safe Mode".

I notice there was a red switch on the back side of the motor.

Any Takers???

[mitch]

I am not sure about the reset have a look in you operators manual you can check the termos if you are in the USA they cheap away 30 bucks or so. have you checked the oil tanks ?
remote and engine tanks

http://www.yamaha-motor.com/outboard...d_manuals.aspx

[CaptainSteve75]

Thanks for the update...looking forward to the weekend to change the thermos...you are correct they are around 30ea plus 4 gasket.

Based on the feed back I received, it looks like the thermos are bad.

The honest fellow disconnected the alarm...I guess you live and learn.

Water temp is cold no matter how long you run the engine. According to mannual, Thermos are stay normally closed until temp rises, thermos will open allowing water to cool engine. eventually end up going bad and get stuck in the up open position, and not sevre the purpose what they are intended to do.

Just to clarify , do you know if I need to reset anything in the engine once I install new thermos or wil the motor reset itself

[99yam40]

Did you try to find your owners manual and see what it said about reset?

Check the PRV also, if it sticks open it will cause a low speed over temp.
Thermostats normally fail to open causing over heating, but could fail open if spring breaks or too much corrosion around them

[CaptainSteve75]

Nothing on the manual about the red switch on the back of motor.

Manual does say to swap out thermo's every hundred hours...Pumps every 600...I am just changing the minimal stuff...without knowing the history and no gauges...so far with thermo's I am under 500...I just want a fresh start.

I look foward to thank you all soon for all you help and support.

If anybody has suggestion (youtube Vid) for timing let me. know.

[mitch]

zeee switch

YEP have a look at i think page 5-9 switch is emergency oil fill also reset info turn key off and on in op book same area.

fail safe is 2000 rpm

I have paid 90 for a thermo in Australia i now am ordering parts from the usa even volvo penta parts and telling everyone that know that we are being ripped off.

boats net great service you provide

[CaptainSteve75]

Could not find anything on a PRV (Pressure Relief Valve) or AKA Poppet for Yamaha...

Still trying to find out what the ____ is the toggle switch covered in red located on the back attach to the CDI Unit on back purpose.

[CaptainSteve75]

YEP have a look at i think page 5-9 switch is emergency oil fill also reset info turn key off and on in op book same area.

fail safe is 2000 rpm

I have paid 90 for a thermo in Australia i now am ordering parts from the usa even volvo penta parts and telling everyone that know that we are being ripped off.

boats net great service you provide

Sorry Mitch for some reason I did not see this message...Are refering to pare 5-9 in the SELOC 1997 -03

[CaptainSteve75]

OK...This is what I did so far:

As a fresh start, I would
1) replace both tstats #8 plus gaskets. ***Done***
2) replace water pump with entire kit. #18 ***Done***
Boat Parts
3) Fuel pumps (done). ***Done***
4) Spark plugs. ***Done***
5) Change lower unit gear oil. ***Done***
6) Link and Sync. ***?***

What does link mean?

Took it out today Sat. 20th 3/2010 after installing the above mentioned. Symptoms have gotton better...but still not running faster than idle.

Watch the Vid:
YouTube - 1999 Yamaha S200 RPM's bounce up and down passed idle speed