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2001 Yamaha OX66 is sounding the temp alarm at idle speed. New pump (dealer installed), new thermostats and pressure relief valve. Good pea stream. Alarms goes away after 20 seconds of higher PRM's.
Any ideas?
A couple more questions while I am at it.
When replacing the thermostats other than putting the correct end in first, do they have to be orientated any certain way?
When replacing the pressure relief valve with the newer model, does the round end point toward the engine?
How new is new?
A thermostat upside down will get you an alarm quick!
You had it up to speed and no alarms? Did they forget to replace the woodroph key? I know it's spelled wrong folks.
If the impeller is more than a season or two old and you hit muck/mud/sand often due to your type of fishing you need to replace it again. If this is happening on a just repaired unit bring it back!
How new is new?
A thermostat upside down will get you an alarm quick!
You had it up to speed and no alarms? Did they forget to replace the woodroph key? I know it's spelled wrong folks.
If the impeller is more than a season or two old and you hit muck/mud/sand often due to your type of fishing you need to replace it again. If this is happening on a just repaired unit bring it back!
The therms are in correct-end in first, just wondered if the needed to be orientated in a certain direction. Everything is about 12 hours old. Had the same problem last summer with the temp alarm at idle.
When you say preasure release valve, do you mean poppit or poppet valve? Becuase that is your issue, assuming you have a normal idle speed.
Yes, poppet valve was replaced by me. The manual is incorrect for the new valve. How should it go in? Round end of plastic piece first spring then cover??
Yes, poppet valve was replaced by me. The manual is incorrect for the new valve. How should it go in? Round end of plastic piece first spring then cover??
I can't remember off the top of my head but I don't remember a round end. I thought both ends were star shaped and the longer end goes towards the motor, then spring, then cover. Also clean the area where the valve seats. There are probably deposits there. Another thing to do would be to stretch the spring out a little bit (just pull it). Sounds dumb but it works.
Thanks for the reply. I found my answer. The newer poppet is round as shown below but Yamaha changed the orientation and the round end goes in toward the engine into the rubber grommet unlike shown below. This is not an OX66 diagram but the poppet is the same.
Thanks for the reply. I found my answer. The newer poppet is round as shown below but Yamaha changed the orientation and the round end goes in toward the engine into the rubber grommet unlike shown below. This is not an OX66 diagram but the poppet is the same.
So this drawing is backwards? Good to know for the future.
How do you know it is a temp. alarm as opposed to an oil alarm. When the oil tank on the engine gets to the minimum mark, the alarm sounds.
I guess I don't. The first and third lights on the gauge were blinking and the buzzed went off when I advanced the idle. There wasn't much oil in the tank for sure. I plan on changing the oil filter this winter as I read it can also throw an alarm. The first and third lights were blinking on the gauge.
I guess I don't. The first and third lights on the gauge were blinking and the buzzed went off when I advanced the idle. There wasn't much oil in the tank for sure. I plan on changing the oil filter this winter as I read it can also throw an alarm. The first and third lights were blinking on the gauge.
Don't know about the lights but my alarm went off offshore a few weeks ago. Pulled the cowling and my tank was on minimum. I keep an extra gallon on the boat so I topped if off and kept fishing. Had to top it off again on the way in. Took if to my mechanic. He changed/cleaned the filter on the boat tank, filter on the engine tank and the water trap and all is well.
I guess I don't. The first and third lights on the gauge were blinking and the buzzed went off when I advanced the idle. There wasn't much oil in the tank for sure. I plan on changing the oil filter this winter as I read it can also throw an alarm. The first and third lights were blinking on the gauge.
I believe with overheat all the indicator lights blink on the guage. With low oil only the lowest mark on the oil indicator gauge flashes. Same buzzer with both though.
I believe with overheat all the indicator lights blink on the guage. With low oil only the lowest mark on the oil indicator gauge flashes. Same buzzer with both though.
is the yamaha 0X 66 a good engine? Anything you can share with me about this engine would be of help. THX
is the yamaha 0X 66 a good engine? Anything you can share with me about this engine would be of help. THX
That's been talked about alot on here. The general consensus it is one of the most reliable engines ever made. They are thirsty if you use all the punch. They are strong. However, I'm getting 2.0mpg fishing 35-40 mile trips 20 times a year.
That's been talked about alot on here. The general consensus it is one of the most reliable engines ever made. They are thirsty if you use all the punch. They are strong. However, I'm getting 2.0mpg fishing 35-40 mile trips 20 times a year.
Thats very good mpg if you ask me. I am looking at a boat with a 200hp 0X-66 On it.
225 OX66 Overheat 
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