Early Mercury block vs 59A

Ziggster said:
These things? They look like holes.
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588151
 
Those are the lifter bores. I was initially fooled as well because there is an optical illusion that makes the recess the cam rides in look like a bulge in the block under where the cam should be (and also no lifter bores).
 
3W Hank said:
I will get it up from hottank today and make a puller and then I see whats behind.
I think its OD 3.5/16”.
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If so, then you'd be in great shape if the underlying material is good. You can get pistons from Ross at any size. The key is finding good quality rings FIRST - then order the pistons to match.
 
Bored&Stroked said:
If so, then you'd be in great shape if the underlying material is good. You can get pistons from Ross at any size. The key is finding good quality rings FIRST - then order the pistons to match.
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Last time I ordered custom pistons from Ross, they told me whether or not the size could be ordered with Total Seal metric rings. Make sure you ask like Dale said.

It would be a bummer to order custom pistons and have to use cast iron rings.
 
What to use 1.6 or 1.2 or 1 mm rings.
I will hone with TQ.
TS has almost all rings in mm but I has never bought this diameters.
So first visual, then hone see where it leads then check with TS snd then ask Ross.
They will do what I ask.
 
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I has took out a sleeve and bore is nice behind on this cylinder anyway and I can't say but it feels like this is a factory sleeved block and it will be no suprice behind, but it's a seat for the sleeve ( se picture ) and diameter on that is 3.368" and deepth is 0.10".

The bore is pretty round ( 0.001" oval ) so bore is 3.2693".
Std plus 1/8" is 3.3125".
So get there is + 0.062".

Will remove rest of the sleeves.
If no issues, what is the best do here in final bore vs the 'seat' ?
Block is/was pretty rusty inside.
 

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Some people would bore their flatheads to 3.375". Maybe that's the reason, I can see what you mean. You would still have .020" counterbore .100" deep down each cylinder!
I don't think you'd want to leave it that way. I see your logic but have no answers.
Do you have the equipment to sonic test your cylinder wall thickness?

Al Hook
 
3.368 is seat now so it go clean on max bore 3.375” but it don’t feel to great and it’s nice now at 3.2693”.
Cylinders feel rather thick and I might can sonic test but rust is not easy see needle holes.
I rather not sleeve it up.
-Maybe other ideas ?
 
3W Hank said:
I has took out a sleeve and bore is nice behind on this cylinder anyway and I can't say but it feels like this is a factory sleeved block and it will be no suprice behind, but it's a seat for the sleeve ( se picture ) and diameter on that is 3.368" and deepth is 0.10".

The bore is pretty round ( 0.001" oval ) so bore is 3.2693".
Std plus 1/8" is 3.3125".
So get there is + 0.062".

Will remove rest of the sleeves.
If no issues, what is the best do here in final bore vs the 'seat' ?
Block is/was pretty rusty inside.
Click to expand...
588256
 
Where are the rings compared to the counterbore? The piston usually doesn't touch the cylinder wall above the top ring. If the top ring is further down that the counter bore then you may be fine to rebuild and go without worrying about the counter bore on the top of each cylinder.
 
It was std bore ( in sleeve ) and diameter in block as mentioned 3.2693” so I can just hone ( if rings is there ( 83 mm ) or go 3.5/16” ( + 1.8” ) but then leave the sleeve seat in block as top ring will not be there ( but kind of odd deal )
 
I'd go to a 3 5/16 bore and run metric rings. Also, you can have Ross move the ring pack down a bit (if needed). I would put a nice chamfer on the sharp edge - otherwise it will be hell installing the pistons (rings will catch). Also, you don't want a sharp edge to potentially cause detonation.
 
3W Hank said:
What to use 1.6 or 1.2 or 1 mm rings.
I will hone with TQ.
TS has almost all rings in mm but I has never bought this diameters.
So first visual, then hone see where it leads then check with TS snd then ask Ross.
They will do what I ask.
Click to expand...

I just found my receipt from Ross. Total Seal rings were 1.5MM, 1.5MM and 3MM.
 
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