never buying another Johnson


Stupid motor only lasted 25 yrs. /sarc

Is piston supposed to look like this?

Appears to have eaten a ring. Inside of head looks like tip of piston.

Old girl ran like a top for a long time. Never failed to get me home. Not one time.

Guess it's time to start researching repower options.


---------------------------
17' Henry O Hornet w/ Johnson 88 spl
26' Palmer Scott project hull
14' Bentz-Craft w/ Yamaha 25
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i sure wish that was a 1995 ocean runner. i'd buy the whole setup. im looking for a power pack


_____________________________________________________
Proline 201WA
Aloha 24ft pontoon (LooneyToon)
Old Town stern with 7.5 johnson
Here's a mystery.

That motor on that hull has always done 30-31 mph WOT. I always thought a 90hp should push her better than that but, she ran smoothly, idled nicely, and generally behaved herself if she had clean carbs. Slightly disappointing fuel economy but she's a 25yr old 2-smoker.

Here's the mystery. The last trip, after fishing a spot, 'had a little difficulty getting her to start. She'd spin and fire, stumble, and die. She did it maybe 10 times. Then, got enough start-up lever in her and she fired up and ran. Figuring low speed jets were dirty, I ran her WOT back to the trailer. 31mph.

Second part, on the hose in the driveway, I did a little tidying up of the timing linkage and she went back to purring at idle. I figured since she was warmed up, I do a quick compression test and that was my first evidence of a bad cylinder.

Note that the intake side of the piston face has more carbon build up and there is carbon in and on the dents left by the piece of ring bouncing around in the cylinder. Same is true on the under side of the head.

Question: have I been running on a very weak cylinder for a long time? Curiosity is getting the better of me. I think I'm going to pull the power head and see if I can't get those last two crank case bolts to free up. If I can, will get a piston kit and put her back together. I have no expectation that she'll hold together for very long. But, I'm getting ready to have to buy a new motor. Have been thinking a 115 or larger. But, if a 90 4 stroke will push her near 40mph, I'll save some transom weight and go back with another 90? Decisions... decisions.....





---------------------------
17' Henry O Hornet w/ Johnson 88 spl
26' Palmer Scott project hull
14' Bentz-Craft w/ Yamaha 25
Here's a mystery.

That motor on that hull has always done 30-31 mph WOT. I always thought a 90hp should push her better than that but, she ran smoothly, idled nicely, and generally behaved herself if she had clean carbs. Slightly disappointing fuel economy but she's a 25yr old 2-smoker.

Here's the mystery. The last trip, after fishing a spot, 'had a little difficulty getting her to start. She'd spin and fire, stumble, and die. She did it maybe 10 times. Then, got enough start-up lever in her and she fired up and ran. Figuring low speed jets were dirty, I ran her WOT back to the trailer. 31mph.

Second part, on the hose in the driveway, I did a little tidying up of the timing linkage and she went back to purring at idle. I figured since she was warmed up, I do a quick compression test and that was my first evidence of a bad cylinder.

Note that the intake side of the piston face has more carbon build up and there is carbon in and on the dents left by the piece of ring bouncing around in the cylinder. Same is true on the under side of the head.

Question: have I been running on a very weak cylinder for a long time? Curiosity is getting the better of me. I think I'm going to pull the power head and see if I can't get those last two crank case bolts to free up. If I can, will get a piston kit and put her back together. I have no expectation that she'll hold together for very long. But, I'm getting ready to have to buy a new motor. Have been thinking a 115 or larger. But, if a 90 4 stroke will push her near 40mph, I'll save some transom weight and go back with another 90? Decisions... decisions.....





---------------------------
17' Henry O Hornet w/ Johnson 88 spl
26' Palmer Scott project hull
14' Bentz-Craft w/ Yamaha 25Originally posted by PalmerScott




If the block and crank are good...
http://smellofdeath.com/lloydy/piston_diag_guide.htm



The ENTER-NET Fisherman
I got enough stool to work on around here, but, I gots to know why that piston ate the ring.

The cylinder got hot due to the ring failure or some other cause?

If you get apart, I'd like to know if the locating pin failed...or just old rings.

Show me a four stroke that will run with damage like that.




The ENTER-NET Fisherman
 

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