Thursday, September 25, 2014

I Had A Borning Time. Honing

I did something that I had always waited to do myself and instead of paying someone else to do it.
This is the Hone head that goes into the cylinder and grinds away the metal.

So the normal way you do this is remove the motor, take all the parts off, completely removing everything  because it is always hot tanked and some of the part can be damaged in the hot tanking.
With the plan of looking like it did when the block was first cast from steel in the beginning.
And the machine shop people do not like to work on dirty engine blocks, they would like to be able to eat off of it, before they start machining, the other reason is be able to see any damage or cracks that may be hidden.  So the two way to do this is with a Boring bar or Preseason Hone.
Piston upside down in cylinder
Hones stones, 2 type of grit 80 and 180
 Because the cylinder is under 3 inches a boring bar will not fit.
So in has to be honed.
The bar tool cuts the metal and the hone grinds it away a little at a time.
This is the Feeler gauge in the cylinder with piston  .0015 thick.

The hone is turn with a 3/4 inch drill motor and turned at below 300 RPM to to keep it cool.
And then as you turn it slowly, you have to add honing fluid to help wash away the stone and metal particles.
I pulled the head off engine and remove the pistons and oil pan.
Place a pan under the engine to cache the stuff that fall out.
I had to remove 0.020 inch of metal to install .20 over piston, that is about the thickness of 3 or 4 sheet of copy paper.
I did this to old way, witch is to hone a little and then take your new piston and stick it in the cylinder upside down with .0015 thick "feeler gauge" (feeler gauge is flat metal that is the perifit thickens).
The other way it to buy a "bore gauge" that has a dial on it, that tells you how big the cylinder is.
So the ideal is to be able to slide the piston down into the hole with the feeler gauge in the hole at the same time. You start out, you can not get the feeler gauge in the cylinder then it goes in but it stick really bad.
Then in the end, you are able to push it all the way down with out sticking, needs to  move pretty easy and pull the gauge and it slide easy as will.
The last is to finish hone to get a slight angle 45 degree on the surface to help it break in better.
The last part is to wash out the metal and stone parities away and clean the bottom end as will.
I changed oil the first 100 miles and I change it again at about 1000 mile to get the last of the dirty stuff.
Right now I have 300 mile on the motor and it runs really good with lots more power then it every had. It was going to cost about $200 to have the work done, the hone cost $150. so I saved little and learn a lot, and the next job will be almost free.

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