Post by ShakerNorm on Jun 30, 2010 23:35:06 GMT -5
A few of you have been following me as I rebuild my engine, and I found a new way NOT to paint your cylinders the other day.....
I've pulled the engine apart - finding a very stretched cam chain, chain guides completely shot (almost completely rubbed through the front guide, even
), with the plastic parts of the front guide sitting down near the crank 
.... and not really much other damage to it - lucky for me 
After measuring the cylinder walls to make sure I'm within limits and can get away with stock rings and a hone, I bead blasted the outside of the cylinders to prep it for painting. When I got home, I gave it 4 coats of matte black engine paint and let it dry overnight.
In the morning, I figured that I would bake the paint for a while just to make sure it sets up.... So I preheat my oven (I have one wired in my garage for powdercoating and this sort of thing), and when it hit 400*, I popped the cylinders in for an hour or so to bake the paint.
When the paint had baked sufficiently for my taste, I turned off the oven to let the thing cool. When I finally pulled it out of the oven, something looked a little weird to me.... and then it hit me....
The cylinders are heated to install the bores and I'd set it in the oven with the top up - the aluminum casing had expanded and slid to the bottom of the bores! I wish I hadn't messed up my camera the day before, because I was pretty astonished!
After thinking it through a few minutes - I figured if it works one way, then it should work the other way, too...... So I reheated the oven again, and found a piece of steel plate, turned the mess upside down on the plate and slid it back into the oven for an hour or so. Sure enough - the casting slid right back into place like nothing ever happened! ;D I may have been lucky, but at least there was no permanent damage done, and a lesson was learned.....
It was good for a chuckle, though.
I've pulled the engine apart - finding a very stretched cam chain, chain guides completely shot (almost completely rubbed through the front guide, even
), with the plastic parts of the front guide sitting down near the crank 
.... and not really much other damage to it - lucky for me 
After measuring the cylinder walls to make sure I'm within limits and can get away with stock rings and a hone, I bead blasted the outside of the cylinders to prep it for painting. When I got home, I gave it 4 coats of matte black engine paint and let it dry overnight.
In the morning, I figured that I would bake the paint for a while just to make sure it sets up.... So I preheat my oven (I have one wired in my garage for powdercoating and this sort of thing), and when it hit 400*, I popped the cylinders in for an hour or so to bake the paint.
When the paint had baked sufficiently for my taste, I turned off the oven to let the thing cool. When I finally pulled it out of the oven, something looked a little weird to me.... and then it hit me....
The cylinders are heated to install the bores and I'd set it in the oven with the top up - the aluminum casing had expanded and slid to the bottom of the bores!
I wish I hadn't messed up my camera the day before, because I was pretty astonished! After thinking it through a few minutes - I figured if it works one way, then it should work the other way, too...... So I reheated the oven again, and found a piece of steel plate, turned the mess upside down on the plate and slid it back into the oven for an hour or so. Sure enough - the casting slid right back into place like nothing ever happened! ;D I may have been lucky, but at least there was no permanent damage done, and a lesson was learned.....
It was good for a chuckle, though.
