A series piston rings

[ChickenGrease92]

Hello everyone

 

Im going to be rebuilding my a15 i have laying around, problem is i cant seem to find the right piston rings anywhere.

Rock auto says they are sold out. Im looking for standard size btw

If anyone has a link or supplier they would like to share please do lol

 

Thanks

[KELMO]

That is unfortunate. I had previously got some from RA but it has been a year or so. Within the past year I was able to get some through Nissan, but those may have been the last in captivity. I will try to look around for the part #.

[ChickenGrease92]

I found rings for the a14 pistons, would i be able to use those in my a15? I read somewhere that you can but then i also read that you cant..

 

And thanks for the reply kelmo, if you come across the part number please let me know

[KELMO]

There is some information I have (Nissan E-Fast system) that shows it as a possibility from 08/80 and up. I keep coming up with the same part #. Earlier part #'s do not appear to interchange which I find hard to believe as I though the bore on all "A" motors were the same. I could be wrong, it happens a lot.

I stumbled across a set of pistons yesterday, I will try and measure for a diameter.

Have you started your tear down yet, or are you waiting to aquire parts?

[KELMO]

Can't believe DM hasn't chimed in on this one. Must be out walking.😁

[datzenmike]

The 210 A12 bore is 77mm. The A12 77mm rings do not work with the 1mm over bore A14/15 for some reason. Possibly the rings are narrower on the later A14/15?

 

The B-210 A14 rings match the later 210 A14 but pistons do not. Possibly different dishes. The rods are the same so B-210 A14 pistons and rings should work in the 210 if swapped as a set.

 

A14 and A15 have the same bore of 76mm

 

Standard bore rings for A14 and A15 is 12033-H9810

 

[ChickenGrease92]

Thanks kelmo, and yes i started a parts list and so far ive only pulled the pistons to inspect the rings, and measure for wear.. (found this block at a pick a part btw) 

 

Mike, i believe you are correct. I also have another set of a15 pistons and the numbers on the rods match the ones i pulled out from this block. I think the height of the piston is shorter on the a14 pistons but still 76mm bore? 

[KELMO]

The 12033-H9810 # is one of the ones I found.

Those notes are on the desk at home......dammit.

[ChickenGrease92]

Interesting..

 

Rock auto sent me hastings rings 

Part number HAS 2C6146

But i dont want to install them if those arent standard rings? 

 

Im going to look around for those rings you guys provided above

[datzenmike]

A14 and A15 have the same bores so has to be the stroke that's different.

 

Stroke is 77mm on the A14 and 82 on the A15 so the A15 must have a 2.5mm shorter piston pin height than the A14 piston.

[ChickenGrease92]

Thats what i just saw mike, 2.5mm is the difference. 

 

I put the new rings in to check gaps..

 

my manual says a14/15 should be 0.20-0.35mm for the top ring. Does that sound right??

A few years back i read that some manuals were giving out false/incorrect info, is that true? 

 

I have the datsun 210 all models 1979 thru 1982 haynes manual 

[datzenmike]

Haynes copies from Nissan so there is obvious room to get it wrong. I won't use any specs from Haynes, I only use the FSM (factory service manual) from Nissan.

 

Generally for a stock street engine the ring gap is 0.1mm for 25mm of bore. So if the A 14/15 is 76mm then 76/25 is close to 3 X 0.1 = 0.3mm so well within the 0.2 to 0.35 setting. I would rather have it on the high side because the last thing you want is to over heat and the ends close the gap and touch.

 

Second ring is 0.127mm for every 25mm of bore.

 

 

The gaps would be set wider if you are making more heat, such as from boost or nitrous.

 

 

 

[ChickenGrease92]

 Glad you mentioned that mike, i need to look for a better manual now haha

 

So i believe im in spec, i do want to go on the higher side by a few. So what would you says is good? Like 0.23-0.25? For top ring

 

I wish i was boosted mike haha, but id probly blow it up due to the way i drive😂 my 210 feels like a street legal go kart

[datzenmike]

On 3/22/2022 at 3:27 PM, ChickenGrease92 said:

 

my manual says a14/15 should be 0.20-0.35mm for the top ring.

 

 

If 0.35 is the upper limit and my suggestion is 0.30mm then try for 0.3mm. If you drive it hard on occasion then closer to 0.35mm and if you drive like your grandma the closer to the 0.20mm. The wider choice gives a little more safety if you accidentally over heat the engine

[ChickenGrease92]

Alright. I might have to post some pics cause im pretty sure i just ran into a big problem. 

 

.012

0.30mm

 

.025

0.63mm

 

The top one is the one i believe i should be fitting snug, but the bottom one is the one the fits snug. 

 

Its fucked isnt it? 🤬

[datzenmike]

 Not following. What are you measuring for top and second ring end clearances?

What does the manual say second ring end clearance is????

[ChickenGrease92]

Yes those were for the top ring clearance..

 

The manual says for the 2nd ring it should be 0.0059 to 0.0118 in.

(0.15 to 0.30 mm)

[datzenmike]

In some cases the second ring IS tighter than the top. This is because the heat isn't as high at the second ring. These are old engines and today's numbers may not apply.

 

I would get a second opinion from another source.

[ChickenGrease92]

Ok im gona look around some forums and see what info i can find. 

 

Thanks for droppin some knowledge mike

 

[KELMO]

A day late and a dollar short but I did find them. I am fairly sure these are for an A12 but to find this part # I dug through some rabbit holes and that was some time ago.

And I no longer have access to the information used (I quit that job).

12033-H8915