Motor ran fine all morning then lost power started knocking

[FishtheBull]

1988 Evinrude 60 horsepower vro Ran the motor somewhere around about 4 miles two different spots to fish motor ran fine was going to another spot motor lost power and started knocking I shut it off immediately use the trolling motor and took it back to the boat ramp I spoke to a few people over night no real answers except that they cannot believe it blowed up which that's what I thought went out the next morning started the motor ran fine purr like it always did took it to the lake motor started ran fine went to take off push the Throttle Down got almost up on plane then lost all power started small backfiring out the exhaust and died would start right back up push the Throwdown and the motor would small backfire and die
I have clean the carburetors made no change put a new fuel filter on the motor any advice will help thank you in advance

 

[racerone]

You start with a compression test.----Post your numbers.----Perhaps check the flywheel key since it is backfiring.

 

[FishtheBull]

Will do tomorrow thank you

 

[FishtheBull]

Done the compression check top cylinder 30 PSI middle cylinder and bottom cylinder tested at 130psi so I'm guessing piston or a ring

 

[jakedaawg]

Time for newer motor...

 

[boobie]

Pull the head to see what you find. It could be just a blown head gasket.

 

[FishtheBull]

The motor has very low hours the person I got it from older couple and the used the 7.5 the most to troll they hardly ever used the 60 HP going to pull head tomorrow check it out thanks

 

[oldboat1]

Did the motor overheat? Normal procedure is to replace the water pump impeller when you pick up a used motor. Was the motor pumping water?

Another potential issue involves the type of fuel pump in use -- Are you premixing fuel (50:1) or using the VRO system? Have any alarms sounded?

Like Boobie says, pull the head cover and see what you find. Expect the worst, and hope for the best.

 

[FishtheBull]

No the motor did not overheat changed out the water pump beginning of this year I've had the boat for 3 years yes the motor was pumping water very strongly and yes I am a stickler on mixing my own fuel and yes it is 50 to 1 and I use the Johnson Evinrude mix oil

 

[FishtheBull]

The motor has ran very strong for 3 years never a problem never miss every time I started it starts with a quick turn of the key purred like a kitten up until it done this running some errands and then I will be pulling the head this afternoon and yes with my luck I'm expecting the worst thank you for the info I will get back to you guys

 

[FishtheBull]

Okay I have pulled the head off and pretty much found the worst top piston number 1 is beat all to **** with a big chunk missing out of it any idea what would have caused this and another question I worked on several vehicles done about everything you could do one but have never worked on a boat motor should I proceed or should I take it to a professional

 

[racerone]

You will be shocked at what it costs at a big shop.---Parts and availability is also a factor.-----Pictures or model # must be supplied / posted.-----If you take your time you can do it yourself.----Your location ?

 

[boobie]

If you decide to do it yourself get a Factory service manual. Stay away from the Selocs or Clymers as they are good only to use in the old out house replacing the Sears catalog.

 

[FishtheBull]

Racerone I live in Forsyth Mo and I know all to much about a boat shop I think I would sell the boat and buy a kayak LOL Not!!! I looked at the motor for most of the day yesterday and first part of today before I decided I was going to do it and I would much rather work on a outboard then a vehicle any day ....Boobies thank you for the advice I will get one ordered instead of trying to find one around here thanks for the replies and info!!