2003 50tlrb

[FirstBoat50tlr]

Hi this is my first post on the forum. Just picked up my first boat. 2003 Whitecap 161 with a 2 stroke 50hp on it.
Previous owner said “potentially bad gas in the boat” so i pumped all 16 gallons out and plugged in an external just to see if i could get it running. Still nothing.
Couldn’t get her to turn over and idle. Read a bunch on this forum. People suggested rebuilding the carbs, replacing fuel filter. I’ve done both. Yesterday I put all the carbs back on and plugged all the lines back in. Turned over and idled well on the 3rd key turn. Walked over to the engine and pressed down on the throttle linkage. Engine started bogging down and farting. Adjusted all the carb needles out (left turns) to see if I could get more fuel in there and it didn’t work. Anyone have any suggestions on what to do next? I can only throttle it open a tiny bit before it bogs down.

[99yam40]

need to follow the link and sync procedure in service manual anytime putting the carbs back on.
it include checking/setting the timing

making sure the timing is correct and advancing as it should can be seen with a timing light.
if timing is advancing and in spec , it could be not enough fuel.

If the main jets and passages are plugged up the motor can idle but not get enough fuel to gain RPM and carry load

did you check the compression before buying?
is the red prime start lever in the auto/normal position?
is the fuel pump good?

[FirstBoat50tlr]

Thanks for the reply. Compression test was good. I don’t have the service manual and it appears I will need to buy one online, which I will do.

the prime lever confuses me because it doesn’t have a simple pointing arm at which setting it’s on. Mine reads only “open” and “close” It currently is resting at what I believe to be “normal” mode which is turned all the way in (counterclockwise) see photo in attachment

Purchased a fuel pump and will install it later in the week

[FirstBoat50tlr]

[99yam40]

Hi this is my first post on the forum. Just picked up my first boat. 2003 Whitecap 161 with a 2 stroke 50hp on it.
Previous owner said “potentially bad gas in the boat” so i pumped all 16 gallons out and plugged in an external just to see if i could get it running. Still nothing.
Couldn’t get her to turn over and idle. Read a bunch on this forum. People suggested rebuilding the carbs, replacing fuel filter. I’ve done both. Yesterday I put all the carbs back on and plugged all the lines back in. Turned over and idled well on the 3rd key turn. Walked over to the engine and pressed down on the throttle linkage. Engine started bogging down and farting. Adjusted all the carb needles out (left turns) to see if I could get more fuel in there and it didn’t work. Anyone have any suggestions on what to do next? I can only throttle it open a tiny bit before it bogs down.

if you were moving the throttle plates without moving the timing arm/linkage, the timing is not advancing so it will not run properly
yes the PS has 3 positions,
full counter clockwise should be the normal/auto position

[FirstBoat50tlr]

if you were moving the throttle plates without moving the timing arm/linkage, the timing is not advancing so it will not run properly
yes the PS has 3 positions,
full counter clockwise should be the normal/auto position

Here is what is happening.
https://youtube.com/shorts/0alUvdT5ffw?feature=share

[99yam40]

looks to me you are not moving the timing linkage when you do that.
why do it that way?
just put in gear and advance the throttle like normal

also when you put the carbs back on you have to follow the link and sync procedure, every time.
that includes setting the timing correctly.
at idle the pointer should be pointed at the bottom mark on CDI and at the top mark at WOT

[FirstBoat50tlr]

I’ve done so much to this point. Bought the manual. Here’s where I’m at now:
starts right up!!!
things done: pumped old fuel out the Internal, replaced inline fuel and water separator filter, replaced fuel pump, rebuilt carbs 2x (including a soak)., replaced sparks, replaced all 3 ignition coils.

Issue now:
Feels like not getting enough power, the RPMs are pretty much there but when I push down the on the throttle lever in the water I get to about 1/2 down and Im not really going anywhere. 3/4 down and I’m starting to move a little better but just doesn’t seem right. Takes a few minutes to get to plane on calm water. When I do get going it sounds like it’s being worked hard.
According to Yamaha, a 2003 50hp on a 16’ boat should top out around 30mph. I’m not even close!!!

on the CDI, I’ll upload 2 images for you. Neutral and WOT

[FirstBoat50tlr]

I’ve done so much to this point. Bought the manual. Here’s where I’m at now:
starts right up!!!
things done: pumped old fuel out the Internal, replaced inline fuel and water separator filter, replaced fuel pump, rebuilt carbs 2x (including a soak)., replaced sparks, replaced all 3 ignition coils.

Issue now:
Feels like not getting enough power, the RPMs are pretty much there but when I push down the on the throttle lever in the water I get to about 1/2 down and Im not really going anywhere. 3/4 down and I’m starting to move a little better but just doesn’t seem right. Takes a few minutes to get to plane on calm water. When I do get going it sounds like it’s being worked hard.
According to Yamaha, a 2003 50hp on a 16’ boat should top out around 30mph. I’m not even close!!!

on the CDI, I’ll upload 2 images for you. Neutral and WOT

[FirstBoat50tlr]

https://youtu.be/eAP0f-5uWzw
under a light load
also, anyone hear ticking or just me?

[99yam40]

only pic I see is listed as WOT and the pointer is pointing at idle timing mark

[FirstBoat50tlr]

[FirstBoat50tlr]

When I push the throttle down, the pointer moves from the top (idle) to the bottom mark /, not sure what that little dot represents near WOT

[99yam40]

looks backwards to me.
what does you service manual show you for setting it?
Best to hook up a timing light and see what the actual timing is at idle and WOT just like the manual says to.
marks are just something close to set it before starting

[FirstBoat50tlr]

I’ll look again but I believe I set it up the way it’s supposed to be. I’m working on uploading a video again. Is there a cheap timing light? How difficult is it to do.