73 merc rebuild help.

[Texas Prowler]

Would you trash this block or keep building despite the dimples?

 

[Texas Prowler]

Anyone?

 

[jbcurt00]

Dont forget it is the holiday season and many are spending time off line or using time off from work to actually work on their own projects. It may take longer for questions to be answered.

Pix posting help
http://forums.iboats.com/forum/forum-rules-and-guidelines/9938375-photo-upload-tutorial

 

[racerone]

Those dimples are likely from the lower ball bearing.----Perhaps this motor has been rebuilt before.---Any sign that it was apart before ?----I would certainly take the reed block apart to measure clearance there.

 

[Texas Prowler]

The only sign of a rebuild i can find is a arrow scratched into the reed block pointing upward. How could the lower ball bearing cause those dimples at the top of the cylinder? I figured it was detonation but I guess I'm wrong. The pistons are caked with carbon but otherwise smooth without dimples

 

[Texas Prowler]

Well I spoke with my outboard shop and he says he can weld and smooth out the cylinder. I sent him some pictures and he says he feels confident in being able to repair the damage. I told him if it needs to be sleeved I'll just trash the motor. Now i just need to find time to drop the block off and have him check it out.

 

[Faztbullet]

Your pic's are gone but if dimples are in the top of cylinder dome don't worry about it. Just be sure there are no pieces of metal embedded in dimples or punched thru jug into water jacket. Inspect the labyrinth seals in reed block as they should have sharp edges and if flattened down or brassy look it needs replaced.

 

[racerone]

Simple , the cage on the lower bearing fails.-The balls are now loose.---They end up on top of the piston and make those dimples.-No damage on the piston ??---Simply means block was apart and piston was replaced.---Have seen this on occasion, yes I have !

 

[Texas Prowler]

Your pic's are gone but if dimples are in the top of cylinder dome don't worry about it. Just be sure there are no pieces of metal embedded in dimples or punched thru jug into water jacket. Inspect the labyrinth seals in reed block as they should have sharp edges and if flattened down or brassy look it needs replaced.

I Will pull the reed block apart once i get home and figure a way to post pics. Thanks man

 

[Texas Prowler]

Simple , the cage on the lower bearing fails.-The balls are now loose.---They end up on top of the piston and make those dimples.-No damage on the piston ??---Simply means block was apart and piston was replaced.---Have seen this on occasion, yes I have !

If this block doesn't check out for a rebuild I'll trash it. I can't dump a ton of cash into something with zero sentimental value.

 

[Texas Prowler]

Damaged combustion chamber

 

[Texas Prowler]

Same

 

[Texas Prowler]

cylinder damage

 

[Faztbullet]

Wont hurt a thing....bore it and go!!!!!

 

[Texas Prowler]

Wont hurt a thing....bore it and go!!!!!

Ok thanks man. I'm trying to get the reed block apart from the crank but not having any luck. I don't want to beat it up trying to get it off. Is there an easy way to remove the reed block?

 

[Texas Prowler]

Also i can wobble the reed block on the crank so I bet it well have to be replaced...

 

[Texas Prowler]

No Title

I'm really starting to think of ditching this outboard...

Anyone have any good words? The crank journal that the reed block rest on has grooves from the reed block. How will this affect performance of this engine is rebuilt? Thanks!

 

[Texas Prowler]

No Title

Crank journal....

 

[Texas Prowler]

The lower main bearing has a good wobble to it...

 

[Faztbullet]

The upper bearing failed at sometime thus the dents in cylinder head. Someone tried to repair engine by replacing piston but didn't realize the excessive play wore the reed block. Polish the shaft with some 240 emery cloth and install a good reed block(PM me if you cant find a good used one) and repair cylinders(bore)