Install Pistons & Rings

[EngineerDoug]

Hello all,

Soon I will be installing my new pistons & rings in the freshly bored 383. I think I am up to speed on gapping the rings, but I am reading conflicting opinions on how to properly lube the piston/ring assembly before inserting it in the bore. Here goes:

1) Lube the wrist pin with motor oil.

2) How to lube the piston itself? The mantra used to be, slather it in motor oil. But is this the
correct way to do it? I see people advocating WD40 over motor oil.

3) As for the rings, many folks warn of problems seating moly rings, and here again suggest
using WD40 instead of motor oil.

So how do the pros do it? Motor oil, or WD40? Thanks!

 

[lewtot184]

i get a quart of motor oil with a fair amount of zddp. put it in a container that will allow the piston with rings to be submerged. submerge the piston/rings/rod combo, take it out, wipe off excessive oil, align rings and install. something important is to wipe the cylinders down good. i'll use ATF or a good lighter weight detergent oil to make sure walls are clean. any black or gray on the wiping cloth/towel indicates dirty cylinders.

 

[Mark B]

Ya I know things have changed. Years ago I just slathered them in motor oil and maybe a bit of white lithium on the skirts. But that was using plain cast rings and chrome oil rings. I will be watching this to see what the more schooled builders are using.

 

[oldbee]

1.- yes 2.-slather w/oil 3.- last moly I did they said (1/2? throttle to 60mph,coast down to 20mph,repeat,repeat) If i remember and it was a long time ago, the smoking stopped on about the 3rd-4th repeat. Coasting really sucks up fresh oil on the rings to help seating. I used a flex-hone at 400grit, I think, on the cyl. bore; with their special oil, have to use it. WD-40 on anything? NO

 

[lewtot184]

i never have smoking issues, start-up or driving. assembly lube would be another option but i prefer a total immersion to let oil flow around the pin and ring lands.

 

[IQ52]

As I would do it com....plete.........ly different I will just keep it to my self.

 

[69L48Z27]

Very lightly coat piston sides/rings with engine oil. Definetly not excessive.

 

[dvw]

I used to dip the pistons and make a huge mess. Last 15 years I've done them like this; Coat the pin with assembly lube, I like GM EOS or Michigan bearing guard. Then install the piston on the rod. A couple drops of oil out of a squirt can in each ring groove before the ring goes on. Wipe a finger full of oil into each skirt, not dripping off just damp. Wipe the bores with trans fluid and white paper towel until the towel comes out pure red, no black. Spray the bores with WD 40 and apply bearing guard on the rod bearing and you're ready for install. No mess, no scuffing, immediate ring seal.
Doug

 

[Garys1969RR]

I had always dunked the piston up to the wrist pin in motor oil, as oldbee stated. On the last 451 I built, I just squirted oil on the piston, rings and into wrist pin oil holes. Then on break in, I accelerated at half throttle, coasted down letting the engine slow the car, then repeat a bunch of times. That worked good. I have heard of a special assembly spray for the rings, but never have tried it. I think the modern rings break in fairly quickly, and too much oil can actually hinder that. I would check with your ring manufacturer, and follow their directions.

 

[65-440]

What I did .... clean cylinder bores with lacquer thinner, a light wipe down of motor oil with a lint free rag and same light wipe down on the piston/ rings. No trouble on startup, no smoke, runs like a champ !

 

[moper]

I use assembly lube on the pins, and WD-40 on the bores and rings. Have been for years.

 

[dieseldazzle]

I do wipe the bores clean with atf. I've built atleast 200 motors and at least a third of them just hone and replace rings and polish cranks (ford 5 liter days)

Ive always used some wd40 on the bores and ring pack and called it good.

Built 90 horse 4 cylinders and 960 hp e85 v8 done em all the same

 

[bm02tj]

I like to see the bore scrubbed with soap and water with a good brush and rinse with hot water and blow dry then wipe with a thin oil and white rag
If you have any darkness re wash

 

[bigbluedodge]

I like to see the bore scrubbed with soap and water with a good brush and rinse with hot water and blow dry then wipe with a thin oil and white rag
If you have any darkness re wash

I do this. When you rinse oil the cylinders IMMEDIATELY..... they will rust in minutes.

 

[Challenger340]

The change to square cut Oil Rings a few years ago caused lots of problems for many, hence I believe anyways, the WD40 thing became popular as a surefire way to increase friction on startup for good ring seating on startup ?
Nowadays, it matters NOT who's ring box you open, from Total Seal to FM they are ALL using Hastings square cut Oil Rings, which require a little more "special" Cylinder Wall prep for good seating that many Machine Shops may have not kept up with ?
I would be hesitant to use just WD40 if the "correct" cylinder wall plateau finish is present for square cuts, but if it isn't ? WD40 is probably best ? LOL !
Maybe ask the Shop who Machined it what Cylinder Wall prep they used ? and what they recommend ?

 

[moper]

Mine has a good profilometer, Rottler HP6A honing cabinet to properly hone, and their own dyno cell. They do a lot of local circle track work (read that as engine rules) and as a result they've used to really get into wall finishes to maximize. They reinforced the choice I made years ago. Too much oil is not good for ring seating assuming the bore finish is right. Total Seal has it's own dry lube for the zero gap rings too but I've only used Childs & Albert gapless - which were fine with WD40...lol.

 

[dvw]

The blocks that I use WD 40 on are all plateau honed. My machinest worked at Roush doing their NASCAR blocks. He was the one who put me on to it.
Doug

 

[mopar 3 B]

The change to square cut Oil Rings a few years ago caused lots of problems for many, hence I believe anyways, the WD40 thing became popular as a surefire way to increase friction on startup for good ring seating on startup ?
Nowadays, it matters NOT who's ring box you open, from Total Seal to FM they are ALL using Hastings square cut Oil Rings, which require a little more "special" Cylinder Wall prep for good seating that many Machine Shops may have not kept up with ?
I would be hesitant to use just WD40 if the "correct" cylinder wall plateau finish is present for square cuts, but if it isn't ? WD40 is probably best ? LOL !
Maybe ask the Shop who Machined it what Cylinder Wall prep they used ? and what they recommend ?

What would the correct cylinder wall prep be for square cut rings?

 

[mopar 3 B]

i looked up plateau honed. Understanding the process left me with more questions than answers like are we not getting the proper width rings for our old pistons? On new pistons with narrow ring lands if the original honing looks good why not just clean the cylinder walls and install pistons?