Question about honing and rings

35th T-bird SC

Registered User
I read a couple articles on this matter and tests have shown it is better to NOT hone IF you use cast iron rings because the rings will do it during the break in process. They say that by roughing up that nice smooth surface only creates valleys that will later contaminate the engine with microparticles. It says that the rings will now smooth the valleys out causing the cylinder to grow larger and the piston being the same size creating exsessive clearance. So can a proper break-in with iron rings make up for not honing and cause less damage over time? I bought Hastings rings. They are made of Moly, what is moly, Is it a form of iron? I just never honed before and I don't want to mess anything up and this article has me thinking twice. Need opinions!
 
I haven't done a rebuild in a long time but my understanding was that the crosshatch created by honing the cylinder walls helped with oil retention for lubrication. Maybe I've forgotten more than I remember.
 
As you know I have a SC that was apart at about the same mileage as yours. 85k. I had my block honed and I installed the same Hastings moly rings you are planning on using. I have 3500 miles on it now and the rings seated just fine. If I were you with a broken piston, I would consider rebuilding the entire engine and having the moving parts rebalanced. Of course cost is something to consider but it sure takes a lot of effort to pull one of these engines out.

At least the first time it does.

:)

Good Luck
 
Yea I have 6 pistons on order. I might just take it to a machine shop and get it honed and cleaned out. What's the going rate for a job like that?
 
If you're thinking of having a machine shop do a glaze-break job then you might want to call and cancel that piston order until the machine shop has had a look at your block. Last time I looked, and it's been a few years, the cost for a basic overbore and finish hone was $10 per bore. If torque plates were used the cost doubled to $20. I can't see that a glaze-break job would be all that much cheaper than a basic bore and hone.

IMO a proper bore and hone job would be much superior to a quick-n-dirty glaze break.
 
I agree. If you are looking at new pistons. Boring the block would be a better fix. I messed up my crank in a botched balancer bolt repair (can't drill straight......). Thats why I pulled mine apart. It really did not need bored as it checked out to be within spec. With the cleaning and honing along with new cam bearings and freeze plugs I think it was around $200. It would have cost me another $100 bucks to get it bored, plus the cost of the pistons ($150?) and $180 to get the reciprocating assembly rebalanced. In your case you would add another $50 to a $100 bucks to get the crank polished or turned.

Then its Gaskets, Water pump, timing chain, rebuilding the heads, BHJ balancer and on and on........
 
I don't beleive your rings are made from Moly, or 4130 chromemoly,steels.
The moly is a inserted in a groove cut in the side of the ring.This is
to lessen wear on the ring and cylinder wall.

I would use only Total Seal rings.And hone with a 500 grit hone.No coarser
than 500.I to beleive coarser hones promote excessive wear and blow-by .

You can use the rings you have,but install a Total Seal ring in the top grove of piston.
This will give you less than a 2% leak down.And always use torque plates when boring
or honeing.And the block should be well above 100 degrees with the use of hot cutting fluild
when honing.Don't take your motor to a regular machine shop,Go to a machine shop that
has a racing engine building back ground.If you are looking for the best machine job.

Randy
 
the moly rings is only the facing of the ring the is molybdenum. these rings have a good service life under scuffing conditions. but only the top compression ring is moly the 2nd ring will be cast. so let the machine shop know what kind of rings your using becuase they have to have the proper finish on the cylinder wall to rough will chip the facing of your rings and not settle at all to smooth and they will also not settle.... also if i were you id bore .020 over if your getting new pistons considering any size cost the same might as well have all clearences back to specs..
 
Any store that carries Federal Mogul/Sealed Power parts should be able to get you oversize pistons and rings. .020" or .50mm over will be plenty.

Have the shop measure the piston-bore clearance on your old pistons before ordering new pieces. Up to .004" clearance would be ok. You might be fine with new stock pieces. A few thou (like .002"-.003") wear in the top 3/4" of the bore isn't anything to be concerned about.

The Total Seal rings are a good idea, but standard moly(faced) rings would serve quite well in a stock to mild motor.
 
This place sells them online .50mm are 31.89 and sold in packs of 6.

http://www.rockauto.com/

You have to type in the search area the part number from the Sealed Power section of the Federalmogul site.




http://www.federalmogul.com/cda/homepage/index

SUPERCHARGED
SEALED POWER

3.8110


COMP: (2)1.50mm OIL: (1)4.00mm
COMP DIST: 1.607"; PIN DIA: .9122"
RECESSED HEAD .170" DEEP

Piston H675P 89-95 6
Piston
EXCEPT DISPLAY STANDARD SIZES ONLY H675P.50MM 89-95 6
Piston
EXCEPT DISPLAY STANDARD SIZES ONLY H675P.75MM 89-95 6
Piston
EXCEPT DISPLAY STANDARD SIZES ONLY H675P1.00MM 89-95 6
 
Thats all they show on the website but when you search on the partnumber it brings up what I have posted. Just plug in H675P.50MM as the partnumber under the partnumber search option and they come up.
 

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I would have the machinist measure the bores for size, taper and out of roundness before I bought any pistons because you may or may not need oversize pistons. I tore my engine down at 128,000 miles and the bores were just fine for std size pistons. But me being as anal as I am bored the block anyway and now I wished I had'nt done that because I've lost an oversize to use in case it damages a cylinder and I really need the overbore in the future.
 
That's exactly the reason I want to leave it standard. Unfortunately I already ordered the pistons but it won't be a problem to return them if the machinist tells me tomorrow he couldn't hone it without going oversize.
 
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