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Replacing Piston Rings......HELP Please.

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Damn that's a lot more than i thought i was going to pay for rings... :blink:

 

:lol: i just (RE)paid $11 (ea!) to replace the broken oil ring.

i got 2 so i dont break another one :cursing:

 

 

if your rod bearings are 0.25mm over, i have a spare set avail (clevite)

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i currently have the pistons and bearings out of my truck and im ready to put them back in. however i cant seem to remember if the lil notches for the rod bearings were. both top and bottom have a notch, do they both go on the same side or opposit sides?

DV

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Look on each side of the rod and the cap. The number one rod will have a 1 stamped in it just above the rod cap. The rod cap will also have a 1 on it. They should be assembled with the 1s together on the same side. Like this:

 

R

O

D

 

1

-----

1

ROD

CAP

 

 

BTW the piston top will have a notch on it. Face the notch toward the front of the motor. Here is a Z24 and a KA piston. The dot at 12 o'clock on the first one and the dot at 7 o'clock on the other would be facing toward the front of the motor.

 

http://i138.photobucket.com/albums/q251/datzenmike/L%20Z%20Heads%20and%20Motors/720stuffKA24Epistonrod011Large.jpg[/img]"]720stuffKA24Epistonrod011Large.jpg

Edited by datzenmike

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13zr8ya.jpg

Ok I am not familar with the plastigauge. I am about to reassemble my engine (never done this) and want to do it right.

1. Where do I get one?

2. How is it used.

 

3. my engine is .040 over. How do I check the gap for the piston rings or does this stay the same?

 

I may have more questions through this process so bear with me.

 

Here let me try and help you out.

 

Plastigauge is used to determine bearing clearance. It can be bought at most any parts store. It is a "waxy" string that comes in a paper sleeve. The piece of paper in the photo that is being held to measure the width of the crushed plastigauge is actually the wrapper it comes in. Plastigauge comes in varying ranges. This one is .001

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Dave, sdsurf's post is a bit stale but your info is not. :D

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Hey, I have a question to add to this. It was slightly mentioned earlier, but I have an L18 in my 71 Wagon that smokes BAD. The engine was supposedly rebuilt 10k ago, so I'm thinkin' perhaps they put a ring in upside down. You can't really do this in-car procedure in a 510, can you? Seeing as how the crossmember has the engine mounts attached? Actually, as I'm writing this, I'm thinking of all new reasons why I shouldn't attempt this(One of which being that I'm about to do a KA swap :cool:).

But anyhow, I saw that this wasn't really touched on much, but for the sake of the fact that it is SUPER important, what do you say to justify honing the block with the crank and bearings still in? I mean, the cuttings and the oil are bad news for your happy lil' bearings. Is there anything you could maybe suggest, that would be an easier alternative to flipping the entire truck upside down? :unsure:

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Hey, I have a question to add to this. It was slightly mentioned earlier, but I have an L18 in my 71 Wagon that smokes BAD. The engine was supposedly rebuilt 10k ago, so I'm thinkin' perhaps they put a ring in upside down. You can't really do this in-car procedure in a 510, can you? Seeing as how the crossmember has the engine mounts attached? Actually, as I'm writing this, I'm thinking of all new reasons why I shouldn't attempt this(One of which being that I'm about to do a KA swap :cool:).

But anyhow, I saw that this wasn't really touched on much, but for the sake of the fact that it is SUPER important, what do you say to justify honing the block with the crank and bearings still in? I mean, the cuttings and the oil are bad news for your happy lil' bearings. Is there anything you could maybe suggest, that would be an easier alternative to flipping the entire truck upside down? :unsure:

 

alot of mistakes could cause that, i have seen a job where the guy lined all the pistion ring gaps all in on line and not staggered, it was not a good idea,

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Definitely use the plasti-gauge. I thought I'd save time without it and just got my engine completely re-built and put in. Knocks like a sonofabitch. Now I have to pull the whole damned thing back out and figure which rod bearing is out.

 

Re-ring kits usually have gaskets.

 

Check and double-check your tolerances. Double-check each internal nut/bolt and make sure it's torqued to spec. It'll save time in the long run, and you can be sure you did it right instead of being like my dumb-ass and doing it twice.

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Email from rock auto!

 

Thank you for the email. I can certainly tell you what is included with this

kit. Here is a breakdown for you:

 

-Connecting Rod Bearing Set (Sealed Power Part # 4-67230CP)

-Economy Piston Ring Set (Sealed Power Part # E-366X)

-Gasket Kit (Sealed Power Part # 260-1060: Includes valve stem seals)

 

even more than i thought.

 

Sorry for the old bump, but this is what I'm looking at.

Has anyone ordered this or used similar "Sealed Power" parts?

This thread was extremely helpful. The last engine I did this to was the A15 in my 1981 210 wagon back in 1997, and it was good for a refresher!

 

Dan

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Sealed Power is probably the largest american supplier of piston rings. It is not an off-brand. Can't tell you how their quality is right now, but they have been good in times past.

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I personally would suggest replacing the rod bearings. In addition, double check the Ring gap, and all of the other measurements.

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Date, check it.

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I'm about to hone and replace the rings in my 620.. This is very helpful! The guys that used the flex hone or dingle berry hone, which size did you get and what grit? 

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Get a ball hone. Not the other types. Get a small one for 70 to 85 mm bores. Get the fine type.

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Okay, I got my cylinders honed out, washed the cylinders with soup and hot water (pressure washer) and measured all the rings in each cylinder (ring gap). I used sealed power rings and all the ring gaps were great for a block with a 153k on it! I put new rod bearings in, std size just like the ones I took out. The crank seems to turn without any lag (excluding the piston and rings) but I would still like to plastigauge the journals. What is the specification for the oil clearance between bearing and journal? .002?? Thanks!

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L20B main bearing clearance is 0.0008 to 0.0024" Rod clearance is 0.001 to 0.0022"

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Okay, I got my cylinders honed out, washed the cylinders with soup and hot water (pressure washer) and measured all the rings in each cylinder (ring gap). I used sealed power rings and all the ring gaps were great for a block with a 153k on it! I put new rod bearings in, std size just like the ones I took out. The crank seems to turn without any lag (excluding the piston and rings) but I would still like to plastigauge the journals. What is the specification for the oil clearance between bearing and journal? .002?? Thanks!

 

Sounds like everything went together pretty well if it's rotating good.  The piston and ring warehouse here in town where I get all my parts, sell alot of sealed power ring sets and I like em. I have plastiguage but rarely use it.  The crank journals get hardly any wear if you change your oil and dont forget to install the driveshaft for the oil pump (different engine Long Story)....

 

The cylinder walls will wear much quicker than the crank. I've been suprised at the ring gap on a couple of L engines. I had way more clearence than called for so I know the cylinders were worn. I still went with standard size rings and was satisfied with the results.

 

 The engine I'm building now needed boring and this was the 1st time I've had to file down my rings for proper end clerence. The crank checked within specs, so  I used standard size Clevite bearings.

 

Don;t forget to use the plastic protectors that fit over the end of the valve after changing the valve seals. It prevents damage to the wipe lip and could cause your engine to smoke more than it should.

 

.

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A couple of things to note.  A ridge reamer, if needed, is used before removing the pistons.  If there is enough of a ridge, it can cause the ring to catch and possibly break the ring land.  If there is enough of a ridge (that isn't carbon) then you probably need a re-bore and new pistons.  Also don't get carried away with it, if you cut into the cylinder below the ridge you have a good chance of damaging the cylinder which can tear up your newly installed rings. 

 

Piston rings, besides checking the end gap you should also check the side clearance of the ring in the groove.  Also you can check end gap of the rings at the top (1 inch down from the top or so) and recheck it at the bottom of the cylinder.  If the cylinder is in good shape the clearance should be close to the same.  A rule of thumb is .004 per inch of bore for ring gap.

 

When honing the cylinders be sure to turn the crank so the counter weights and the rod ends are not in the cylinder to be hit by the hone.  Ball hones and spring hones don't actually remove that much material.  Rigid hones, however, can be used to change the size of the cylinder. 

 

When reinstalling the pistons be sure to cover the rod bolts so you don't accidentally nick the crank journal.  There are some special caps that are made  but you can use pieces of rubber fuel line to cover the rod bolts.  I usually make them about 2 inches longer than the amount needed to cover the end of the bolts  to help guide them onto the rod journal.  I usually have to cut the sides down so that the crank will fit between them. 

 

After cleaning the head surface of the block, clean the head bolt hole out and run a tap down each hole.  Blow them out to clear any chips out.  Make sure you lightly oil the threads of the head bolts before installing them.  This will help you get a more consistent torque.

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Flip the engine over.  Remove the oilpan and unbolt and remove the crankshaft .  Pull the pistons out through the bottom of the engine block.  Please! mark and remember which rod and piston went with each cylinder. At factory assembly, each bore was measured, stamped on the block with a "tolerance" number and a piston of the appropriat matching diameter was selected for the cylinder and usually had the same tolerance number stamped on its face.  Not all engines left the factory with all cylinders and pistons having the same tolerance marks!  Now measure or run your fingernail over the "ridge".  Time to use the ridge reamer is now! Then hone the block top to bottom.  Proceed with reassembling the engine using new rod bolts as per the original Nissan/Datsun directions.  They are stretch bolts!  It wasn't until Nissan stopped supplying replacement bolts that Nissan said "OK to reuse old rod bolts."  Long life favors new unstretched rod bolts.

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The original poster has an L16. The "original Nissan/Datsun directions" say nothing about replacing the rod bolts.

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Pistons will not come out of the bottom of most engines as it will hit the main journal webbing. 

 

If you replace the connecting rod bolts, you should have the connecting rods reconditioned.  When removing and reinstalling the bolts, it subtly changes the shape of the connecting rod end.  Not saying it won't work, I wouldn't do it though.  Ask any machinist in a performance rebuilding shop. 

 

The only bolts I have heard of using a torque stretch bolt are head bolts and those are only on specific engines.  The bolts are torqued to a specific poundage and then turned a certain number of degrees, this puts the bolts into what is called the plastic stage were the bolts are stretched.  They cannot be retorqued or reused.

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make sure that the rings are off set from each other. you should look up how many degrees they should be off set. I know i put mine (from 1st to 3rd) 0, 120 and 240. this makes it hard for oil to leak through and burn. 

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Avoid ring gaps in the front to back (piston pin direction) and side to side (thrust direction) of the engine. Instead when viewed from the drivers side try for 45 degrees for the top ring, 225 degrees or 180 from the top ring for the second ring. Install the top and bottom oil rings similar  

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