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Fri Sep 12, 2014 6:27 pm

Hello, I just bought a 87mm AA piston kit to freshen up my 1600.
my question is the pistons are already in the sleeves, do i need to disassemble
them to check/ align the rings on the pistons or can i just install them as they are?

Fri Sep 12, 2014 6:30 pm

Also are the paper gaskets sufficient or should i use a thin layer of sealant between the sleeve and block?

Fri Sep 12, 2014 7:02 pm

No need for paper. People say they cause leaks i've just never used them. Use Curil T between the cylinders and case if you can find it.

The pistons have cosmoline on them. They need to have the rings taken off and cleaned. There are several checks which should be done before installation, but as you've asked this question, I doubt if you have the tools or want to check anyways.

Here's some of the things that should be done:

Use a straight-edge across the cylinder holes on the block to make sure they're straight and aligned. If not, the proper thing is to get the case decked.

Measure all the cylinder lengths with a caliper from the seating surface on the case side to the seating surface on the head side and record sizes.

Measure the pistons from the crown to the center of the pin bore and record.

*The steps above can help you to swap cylinders and pistons to get closer matching deck heights.

Use Wet 600 - 1000 grit sandpaper with oil and scour all four cylinders. The passes should be done as equally as possible across the entire inner cylinder. It is done to remove the tiny high spots from the honing process. It will help with cylinder sealing and give you better compression and a longer life.

Clean and wipe the cylinder insides with a white paper towel until the towels stay perfectly clean.

Measure the cylinder I.D.s and recored runout and out-of-round on each cylinder to make sure they're in spec.

Check ring gaps on all sets and compare to the manual. AAs seem to all have wider gaps than too tight. You want to make sure they don't touch ends when inside the cylinder.

Measure piston skirt O.D. and use your numbers to find skirt-to-barrel clearance.

Re-install clean rings on clean piston. Measure ring side-play to make sure they're not too loose or tight.

Check all deck heights and swap pistons and cylinders to get the closest numbers based on your measurements.

Check chamber CC and make sure nothing needs to be altered before assembly.

Make sure that the oil scraper wavy ring is not overlapping itself, but butts up against itself.

Stagger rings appropriately.

Put sealant on the cylinder bases and lightly oil the cylinders and install.

I may have forgotten stuff. At the least, check compression and clean everything.

Fri Sep 12, 2014 7:05 pm

Think about it. Is it easier to pull them out to check and be sure now, or after you install them and start it up and it smokes like a chimney and won't produce power on two out of four cylinders?

Pull them, line everything up, sleep well that night. Your own labor costs you nothing, but trusting someone else you never met to do the job you elected to skip will cost you a LOT of sleep.

Fri Sep 12, 2014 7:29 pm

When building an engine NOTHING can be taken out of the package and bolted on. Every single part must be cleaned, inspected, measured, and fondled with love before assembly.

Fri Sep 12, 2014 7:54 pm

Come to think of it, I did find one ring upside down on one piston when I built mine. Good idea to weigh the pistons when you have them in hand. Mine wound up within a half gram of each other. THAT is a great thing to know as it relieves all kinds of doubts. Being too cautious and checking/double checking/triple checking everything will make you look crazy, but, DOUBT will drive you crazy, all the way around the bend, certifiably insane!!

I'd rather look crazy and sleep well.

Fri Sep 12, 2014 8:01 pm

You think low price chinese parts are perfect and ready to assemble??

Better check everything, or pray........if you believe in that. it might work

Fri Sep 12, 2014 10:09 pm

Yes, check everything. For what it's worth...AA piston/cylinders have been very good for the last 3-5 years in terms of overall quality and workmanship compared to others even Mahle.

My 96mm biral kit all checked out great and were well within .5 gram of one another out of the box.

Sat Sep 13, 2014 4:59 am

2 things - I use Permatex right stuff between the cylinder and case. make sure everything is CLEAN and grease free. You dont need a lot - just a nice bead and then slide in the cylinders and torque the head. Do one side at a time or it will set up before you get things all together.

Keep track of what rings and pistons are in what cylinder. Last set I installed, I only had to file one ring a little and it was questionable if I even needed to do that.

Sat Sep 13, 2014 8:55 am

if you question it...then you need to do it.

Sat Sep 13, 2014 11:18 am

Thank you for your replies, I dont know what I was thinking, Nothing is "Bolt on".
I think racerdave and Axitech nailed it, EVERYTHING needs to be fondled with love and sleeping well is priceless.

Sun Sep 14, 2014 9:46 am

I think thats waht I said. good transulation.

Mon Sep 15, 2014 9:51 am

mark tucker wrote: I think thats waht I said. good transulation.

Transulation.......is that legal in your state? :lol:

Ray

Mon Sep 15, 2014 10:26 am

Check your rings, last set I had, one was chipped.

Tue Sep 16, 2014 12:11 pm

You could not give me a set of AA pistons.

Tue Sep 16, 2014 12:44 pm

^ that's too bad, I've had much better luck with AA than mahles... mahles haven't been worth a crap since around 2000...