Which brands carry moly piston rings/Engine rebuild

[NMcKe97]

Hey everyone, I was curious if anyone knew of a brand that still carried moly piston rings for 86mm flat top pistons or any other good replacement for the oem piston rings.

I've been looking for some the past few days and was just up all night reading and trying to find a brand that offers them but all I can find is chrome and cast piston rings.

From what I've read oem rings are no longer available and sealed power piston rings discontinued there L series moly ring set. I looked at perfect circle, itm, grant, beck & arnley, motorsport, and a few other brands but couldn't find any. If you guys have any recommendations I would much appreciate it.

Last I posted I had half my engine apart for a head gasket replacement and was considering a full tear down. One busy schedule, a few more tows, and I've finally found myself a spot to start working on my car again.

I've gotten the entire lower end disassembled now and everything is in tip top condition, as I'd hope a 168k mile datsun would be. The valves, valve guides, rocker arms, camshaft, cam towers, pistons, cylinders, rings, crank, seals, and main and rod bearings are all in great condition.

None the less I'm going to be replacing what I can with new oem parts or upgrades.

The persons shop I'm using recommended that we re glaze the cylinder walls ourselves.

He rebuilt and overhauled vw engines for 20+ years so I trust his mechanical advice but I'd like to get some advice from people that specialize in z motors on how to prepair a cylinder wall for moly , chrome, or cast iron piston rings.

I know the cross hatching is supposed to be 45-30 degrees and it has to have a certain grit finish but I don't know the exacts.

I've tried to read about it online with lots of vague imformatiom and in how to rebuild your datsun and how to modify your datsun but it doesn't go into enough detail.

I'm sure a big question is why am I rebuilding my engine in the first place. A big reason is simply knowledge and education, another is peace of mind and garunteed quality of work and products.

I've always had confidence in the L series engine quality and know they can reach upwards of 400k+ miles on an original engine, but as I said, I'm curious and wanted to tear it down none the less.

I had a slight head gasket leak into cylinder 1 from the front right passenger side which led me to the tear down in the first place.

While I'm here I plan on replacing my expansion plugs with brass, installing a new timing chain kit, new turbo oil pump, stainless steel or chromed engine fastener/hardware kit, arp con & main cap bolts, arp head studs, arp intake and exhaust studs, oem main & rod bearings, piston rings, all gaskets, all vacuum lines, all coolant lines, some fuel lines, all hose clamps, and a number of other small stuff around the engine bay, electrical, and suspension.

When I get a little more free time I will make sure to upload photos for all of your viewing pleasure and go into more depth on anything else you guys would like to know.

I need to order the parts sooner than later so the shop owner can get back to working on his own baby haha, your help and advice is greatly appreciated.

Please share any and all recomendations/advice/criticism you might have for the piston ring brand, parts/hardware, preperation and assembly, or whatever else, I can't learn enough and really appreciate it!

-Noah M

 

 

Edited September 5, 2017 by NMcKe97

[madkaw]

Couldn't find any 86mm rings or non at all?

Was there any oversized available?

[NMcKe97]

52 minutes ago, madkaw said:

Couldn't find any 86mm rings or non at all?

Was there any oversized available?

I could find 86mm rings but only in cast iron or chrome, I saw a few oversized at .050" but that was about it.

What would be a good ring set in place of moly or oem rings? I want something that will last, either equivalent to the original quality or better if possible.

I heard sealed power and perfect circle were good brands but they both no longer have their moly piston ring set. I guess if nobody has moly rings and I can't find any I'll have to suffice with the next best.

Thanks for the help.

-Noah M

Edited September 5, 2017 by NMcKe97

[siteunseen]

My machinists got me Hasting's for my 83mm 2.4.  Chrome faced just like the OEMs.  They do require a special hone and from all I read they are pretty much seated after the 20 minute run in at first start up.  I like them and they weren't $200.  More like $50

Car runs great, still haven't done a compression check after a year of driving though but I know they're good from plug readings about once a month. 

I think these would be for flat topped pistons.

1981-83 2.8 Litre 86.00mm 3.386 6 2C6142 6142 6 - 1.5mm 6 - 2.0mm 2753cc Eng. 280ZX, L28E, w/o Turbo 6 - 4.0mm

They're $80 from Perfect Engine, http://www.perfectengine.com/Hastings_2C6142_Piston_Ring_Set_p/has-2c6142.htm

[NMcKe97]

Thanks for the recommendation siteunseen. I was just about getting ready to call and see what the ZCarDepot's piston rings were made from and order those just so I can keep this project moving.

Looking at the ring sizes and specs they are all the same size that folks recommend so I should be able to use that set no problem(I don't have my old rings readily accessible so I can't be certain, just gonna send it!)

I'll make sure to double check ring size and clearances with the originals once I get them.

If they're holding up to your standards I'm sure it'll be just right for my application, thanks again for the recommendation. Definitley will have more peace of mind knowing it's what other Z car lovers use in there baby.

Do you know anything about the honing process required to achieve proper piston seating? Is it something myself and a mechanic can do or do I need to take the lower end to a machine shop?

Thanks again for the help and advice, your knowledge is always invaluable!

-Noah M

[siteunseen]

Thank for the kind words, I appreciate them.

After popping the freeze/core plugs out I found a lot of sludge in my 280's block and a TON in my 240's. For the small amount of money in my case, small town prices, I had both blocks chemically vatted then honed by a huge machine the shop has. I'm pretty sure he charged me $75 for the dip and machine hone. You'll get a clean block that will need paint which in turn will look like a new motor when installed. I used brass core plugs for a little extra "wow factor". One $5 can of engine spray paint is plenty for two good coats.

You may want to google the different cylinder hones but if I remember correctly the chrome face rings get a smoother finish with smaller/finer ridges. 

Also I would buy the best timing kit you can afford. You can skimp on most other parts you'll need but don't do it on the timing chain and side guides. You'll see what I realized while doing mine, most parts for these older cars are made at one place but go by many different names. A lot of the part numbers are almost identical. 

If you follow Tom Monroe's How to Rebuild an L motor and use this forum's depth of knowledge from the members you'll have a good expirence and a better motor. 

Cliff

[NMcKe97]

It sounds like that's the route I'm going to take. After the core plugs come out I'm going to drop the block off this afternoon for a hot bath and possibly a hone.

My poor engine had chunks of corrosion and debris in the block so it's a much needed cleaning.

I think that once the cleaning process and everything is done to the block I am going to paint the inside of it with glyptal paint to prevent sludge build up, aid in oil run off, seal any debris if I didn't get it out, and just peace of mind knowing the block is prepped.

I found the original blue paint for the block so I'll put a nice coat of that on once I'm finished.

I've already ordered the brass core plugs and they're on the way, definitely worth the few extra bucks in my book.

I made sure to scour the internet and forums for advice on the timing chain kit and the general consensus seemed to be to buy a Japanese made kit and if you can oem chain guides.

I couldn't find oem chain guides in a price range that fit my budget so I went ahead and ordered the white head performance timing chain kit for 120$(cheap budget huh(sarcasm)). It is "High quality, made in Japan timing chain kit best performance and reliability.  An OE equivalent to the OEM timing parts."https://whiteheadperformance.com/product/oe-timing-chain-kit-datsun-240z-260z-280z-280zx/

I'm sure it'll do the trick but what brand timing chain kits do you like to use/recommend? I'd send mine back in a heart beat if you have something you'd recommend over that set, I'm just kinda learning and guessing as I go.

That book is gold when it comes to information, I bought that along with "how to modify your datsun/nissan ohc engine","Clymer 280zx shop manual","Haynes 280zx repair manual", and "Chilton Z & ZX repair manual". That combined with the numerous forums and webpages I should be able to do most the work myself, should haha.

Thanks as always for your help and advice, it's helped a lot in my tear down and rebuild!

-Noah M

 

 

Edited September 14, 2017 by NMcKe97

[siteunseen]

I have it at home in a file for that car. I'm pretty sure I bought it through amazon.com, $100 maybe? The first motor I rebuilt I cheaped out and threw fifty or sixty bucks away and bought the cheapest one on ebay.

When you take the block in those guys can get you rings and the right finish on the walls of the cylinders. Ask them what they think.