1992 Evinrude 150 aluminum in cylinder

[runninfarmer]

Hello all, I just purchased a 60 degree 1992 Evinrude 150 from a dishonest seller and discovered it had a cylinder with 0 psi compression. The other 5 cylinders were reasonable at 85-95 psi. After pulling the head I found what looks like aluminum chunks coating the cylinder wall. Also looks like it’s from the piston as it had chips in it? Seller had said it started smoking but still had good compression (right lol). Im very experienced working on Evinrudes and have the manual but have never repaired a cylinder/piston. Can I just chemically remove the aluminum? Also I’m assuming this piston is toast? Are they just surface chips on top? What are my options aside from full rebuild? What would cause pistons to chip?
Says my pics won’t upload but I’ll keep trying. Thank you for the help!!

 

[racerone]

Step #1 is to take the motor apart.

 

[racerone]

Step #2 would be to determine the cause of the failure and make correction.-----Otherwise it will fail again in short order.

 

[cyclops222]

It was & is now a parts motor. Someone took out good piston & put in the junk one. It happens. I was ordered to do that at a marina 70 years ago.

 

[Crosbyman]

no sense in beating a dead horse but very unfortunate those things (easy to check) were not done before the sale. If the seller would have balked then you run away ...measured compression on 5 other cyl wasn't to good anyway.

 

[runninfarmer]

I think it would have been ok for that that year, 91 and 92 were lower compression years. I technically got it for close to parts motor value, so I guess I "rolled the dice" sort of speak and this time I lost lol. It was also difficult with how it was laying on the ground to do it, though it could've been done, was just lazy, lesson learned for sure.

As far as rebuilding, if and once I tear it down, what's the best way to remove the aluminum deposits? The cylinder doesn't appear to be scored, just looks like aluminum from the piston. Can a regular hone take off the aluminum? The head was unimpacted. Still unable to upload pics.

 

[racerone]

After removing the aluminum, you need to check and make sure cylinder is still round.

 

[runninfarmer]

Can the crankcase be split with the powerhead still on/piston pulled out by why of using hole in reed box? I saw them do this on a 225, granted that's a different style block:

 

[Faztbullet]

Do not rebuild it till the block is sent to be pressure tested. The early models are bad about water leaks into cylinders from factory glue lines especially #1. The sleeves can be pulled a welded and re-sleeved but not worth it as 91 is a year all to itself, 92-93 are all to themselves.

 

[Faztbullet]

What a hack video!!!! There is no way to wash out honing debris from cylinder ports and crankshaft area. Those new pistons are now worthless. I'll bet motor did run more than 10 hrs before it failed again

 

[racerone]

Can't blame folks for trying.----Some of us know that the technical knowledge of fine machinery today is nowhere near what folks knew 30 years ago.-----Folks are qualified in --" button pushing " ----it seems.

 

[jonesg]

Hello all, I just purchased a 60 degree 1992 Evinrude 150 from a dishonest seller and discovered it had a cylinder with 0 psi compression. The other 5 cylinders were reasonable at 85-95 psi. After pulling the head I found what looks like aluminum chunks coating the cylinder wall. Also looks like it’s from the piston as it had chips in it? Seller had said it started smoking but still had good compression (right lol). Im very experienced working on Evinrudes and have the manual but have never repaired a cylinder/piston. Can I just chemically remove the aluminum? Also I’m assuming this piston is toast? Are they just surface chips on top? What are my options aside from full rebuild? What would cause pistons to chip?
Says my pics won’t upload but I’ll keep trying. Thank you for the help!!

yes if its alum heat transfer from overheating,
, muriatic acid will soften alum deposited on cylinder walls, we do it on snowsled engines. Soak it and wipe it off, repeat til its gone. Don't breathe the fumes obviously. If the walls are gouged then its a waste of bother.
LOts of videos on youtube about this.

https://www.youtube.com/results?search_query=removing+alum+on+cylinder+wall