Blue band Mercury-MORE INFO

[The Brick]

I have a blueband Mercury 65hp outboard and I am mythed. The motor runs great until I get about 500metres out then it won't run above 2000rpm at full throttle.<br />It is obviously when the temperature gets to a certain level. Could it be electrical?<br />Anyone got any suggestions. I'm in New Zealand and it's summer but I can't get out in my boat. <br /><br />It's pumping water okay and we can put our hand under it.It was etching on number one piston and fouling the spark plug. We changed top seal thinking it was an air leak leaning out number one. This seems to have resolved that but we haven't been able to run it long enough to doublecheck. We are getting good spark on all three before it goes into the water. We also serviced the carby. We don't want to rebuild the motor as this is meant to be a cheapy but is siphoning into the fishing fund. PLEASE HELP!!!!!

 

[NathanY]

Re: Blue band Mercury-MORE INFO

Possible overheating. Is it pumping water? Steam? If water, how hot is it? Can you touch it? Possible losing a cylinder? Did you check for spark? Plugs in proper heat range? Post more info if you can.

 

[rickdb1boat]

Re: Blue band Mercury-MORE INFO

Brick,<br />Sounds like an electrical component is getting hot and failing. As NathanY said, pull the plugs right away when this happens and see what they look like(Dry,Wet,Ect) and check for spark at the same time. Bet your pack is going south on you.

 

[hdawg]

Re: Blue band Mercury-MORE INFO

Brick,<br /><br />I know this sound stupid but let me ask you anyway. Is your gas tank vented properly? I have a 1976 3cyl 65hp mercury, loaned the boat to my brother, he tightened the gas cap, engine wouldn't throttle up after about 1/2 mile and ran hot. Check the bulb, is it full or collapsed? If collapsed check gas cap. Like I said this may sound stupid but my brother was not experienced with boats and almost burned up the motor. Thank goodness for cell phones.