Hello,
I have a out of the box new 50hp yamaha. It might be a dealership left over, so maybe a couple years old but I've run less than 50 hours on it (all salt water), and only had it about 6 months. There are other people who use the motor so without guessing and speculation I can't give a very good history.
The Problem
Yesterday: it stalled on someone else and wouldn't restart (I think they were low on gas or forgot the open the gas vent on tank and vapor locked, again specualation)
I pulled the boat out of the water last night and put a new tank of gas on it and she started right up. I also found a piece of throttle linkage detached going to a plastic box to the starbord side of the head/carb. I think they disconnected it thinking it was the start in neutral switch (which it might be)
Today: we were feeling brave so we decided to go ashore for lunch. The engine starts right up and idles perfect. But when given throttle it feels like the 2,000 rpm restrictor is on. It feels restricted right from startup. No alarms are buzzing and the head doesn't feel super hot, so we head for shore. We putput around a bit like this and at some point the alarm does go off, so we stop and turn off motor for a few minutes. It fires back up and does the same thing with the low idle but no alarm. So I stop at a yamaha dealership for lunch and they tell me it's probably a bad impellor or thermostat, so I buy both. I replace the thermostat at the dock before heading back, I also top of the oil injector tank which was about 1/2 full. About 15 minutes after replacing the thermostat the motor just kicks back to life and gives me full throttle.
Now I can't figure out why it would start running 15 minutes after leaving the dock if it was a bad thermostat. Are there sensors on the downstream side of the thermostat maybe? The whole time the motor has had a steady stream coming from the water discharge hole in the back of the case, but the stream from the hose for the water pressure gauge on the front (which is just hanging open) seems weak and inconsistent.
Also I was wondering if the water discharge hole in the back should pee water if I am hooked up to the hose and have the ear muffs on the intake? I can't get water to come out the discharge just using the hose. Do i have to wait for the thermostat to open before it flows? I don't run it with the hose for more than 30 seconds because the lack of water discharge doesn't sit well with me even if the alarm isn't going off.
I have a out of the box new 50hp yamaha. It might be a dealership left over, so maybe a couple years old but I've run less than 50 hours on it (all salt water), and only had it about 6 months. There are other people who use the motor so without guessing and speculation I can't give a very good history.
The Problem
Yesterday: it stalled on someone else and wouldn't restart (I think they were low on gas or forgot the open the gas vent on tank and vapor locked, again specualation)
I pulled the boat out of the water last night and put a new tank of gas on it and she started right up. I also found a piece of throttle linkage detached going to a plastic box to the starbord side of the head/carb. I think they disconnected it thinking it was the start in neutral switch (which it might be)
Today: we were feeling brave so we decided to go ashore for lunch. The engine starts right up and idles perfect. But when given throttle it feels like the 2,000 rpm restrictor is on. It feels restricted right from startup. No alarms are buzzing and the head doesn't feel super hot, so we head for shore. We putput around a bit like this and at some point the alarm does go off, so we stop and turn off motor for a few minutes. It fires back up and does the same thing with the low idle but no alarm. So I stop at a yamaha dealership for lunch and they tell me it's probably a bad impellor or thermostat, so I buy both. I replace the thermostat at the dock before heading back, I also top of the oil injector tank which was about 1/2 full. About 15 minutes after replacing the thermostat the motor just kicks back to life and gives me full throttle.
Now I can't figure out why it would start running 15 minutes after leaving the dock if it was a bad thermostat. Are there sensors on the downstream side of the thermostat maybe? The whole time the motor has had a steady stream coming from the water discharge hole in the back of the case, but the stream from the hose for the water pressure gauge on the front (which is just hanging open) seems weak and inconsistent.
Also I was wondering if the water discharge hole in the back should pee water if I am hooked up to the hose and have the ear muffs on the intake? I can't get water to come out the discharge just using the hose. Do i have to wait for the thermostat to open before it flows? I don't run it with the hose for more than 30 seconds because the lack of water discharge doesn't sit well with me even if the alarm isn't going off.
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