Sealing the rings
 

Hmm, my post disappeared. Oh well.

I am about ready to reinstall my pistons with new Plasma_moly rings. Just wondering what is the best to use for coating the cylinders/dipping the pistons in prior to installing them?

-Chevron Delo 400, high zinc based, diesel oil.
-Marvell mystery oil?
-I had even heard from an old hot-rodder something like paint thinner or Kerosene?
-Other ideas??

Thanks.......
Mike

30wt oil or whatever you intend to use in the oil pan.

That is what I would do.;)

definetly use the same oil you plan to put in the motor for the intial start-up/break in!!!!!!!!!!!!!!!!!!!!!

David

Do engine builders actually dip the entire piston in oil and then stick them in the cylinder?
The best way to make sure that the rings seal (my experience of course) is to make sure that the cylinders are super clean and of course has the correct finish for the rings used. I have always used ATF. After final wash, get all the residue with thinner, I place ATF on a lint free white cloth and saturate it with ATF and wipe out the cylinders and make sure it comes out clean. If not clean again. Leaving a film of ATF in the cylinders. Wipe a small amount around the rings and a spot on each skirt and install. Seals every time.

Stanger;

Different engine builders do different things, I have seen very few dip the piston in oil, I think that was done "back in the day", don't think many do that anymore.........

Your procedeure with clean bores and ATF is just fine.......

All I do after making sure the bores are perfectly clean is give one, maybe two squirts of motor oil in the bore and smear it around the entire cylinder with my fingers before installing the piston..... I give one squirt on the side of the piston at the rings and then smear it around the piston/skirt.........this way was taught to me by an aircraft mechanic.... his biggest concern was that everything including all the tools (sockets/wrenches) was surgery room clean, and all parts received a light coating of motor oil before assembly....... can't remember any engine he built that had any problems........

David

Amen, a clean can is the best . . . . .

Before getting the airplane mechanic to teach me the proper way to assemble an engine,I had done a few, some with o-k results and some with really bad results, that's when I asked this guy to teach me how to "do it right".....

It was around 1995 and I was ready to assemble a 351-W for my 65 fastback....He told me to bring all the parts and pieces to his shop, enough motor oil to fill the crankcase and one extra quart of the same oil and one tube of Lubri-Plate (aircraft engine assembly lube, get it at NAPA).....

All the machine work had been done on the block/crank/heads and everything was clean and ready for assembly when I brought it to him....he began washing everything,again, starting with the block, I asked "why", he said he does not trust anyone else's work and goes over everything with a fine tooth comb and he did....while he was doing that, he gave me a box full of tools (socket/wrenches) and told me to wash every piece in the parts washer and dry them and they had better shine when I finished and they did.......

he put a clean cover over the work table (he does not use an engine stand)(I think it was on old quilt, but clean) and laid out all the parts and then we began the assembly, as he did something he explained to me why he did it the way he did it and it all made since to me.....

Another thing, is he is very slow, double/triple checking everything as he goes, says he likes to do a job only once and not have to take it apart again cause he missed something....

When the engine was finished, we double bagged it and put it in my truck,he told me to install it in the car and then when I thought it was ready to be fired up, call him and under no circumstances should I attempt to start the motor without him there, so I did as he told me. He came and showed me the proper way to pre-lube the motor and get everything ready for the intial start-up. once it fired, he had me sit in the car and watch the gauges holding the rpms at 2000 for 20 minutes....he was looking for leaks and listening for any unusual noises, thankfully, we had no leaks and no bad sounds...
Then after about an hour of total run time, we changed the oil/filter and he told me to hold the rpms to no more than 5000 for about 100 miles or so and then after that drive it like I want to.. and I did just that, now 12 years later that very same motor is still in that very same car and does not miss a beat and has had a fairly rough life along the way..............

Cleanliness and attention to the little details are a must............

David

Oil.
Detergent oil.
The same stuff you intend to run in the pan.
No synthetics for break in.
Just rub some into CLEAN cylinder walls and a thin coating on the rings and the skirts. And don't forget to lube the pins...

Maybe we need to get a professional engine builder to give a word here. I was once told to always assemble and break-in using non-detergent. The reason, I'm not quite sure. Maybe the non-detergent doesn’t kling to the cylinders as well and you get a quicker break-in. All I can say as a hobbiest and X drag racer, that’s the way I’ve always broke in a motor. Other than put-er in high gear and let-er eat.:D

If it aint broke, don’t try to fix it . . . . .

Don’t get me wrong, I’m not challenging your experience, but this is the way I’ve always done it.

Steve W.

So Stranger,

What is the reasoning behind using the ATF? Maybe a little less viscosity helping the rings seat with the cylinder better?

I honed my cylinders with a 240 stone then a 400 stone as recomended for Plasma-Moly rings. I coated the cylinders with Delo-400 15/40. They sure seem awfully smooth.

Mike

They better be smooth with MOLY rings or you wont have any moly left in a short while

Scufty,

They are smooth. In fact that is what worried me. But...It sounds like they ought to be for the Plasma Moly Rings?

If I can do better than burning a qt. of oil every 200 miles at least I will have an improvment.

May have it back together and in the car this weekend. Been a long 6-months.

Mike

Ive been told that if you are running Moly rings your surface should be darn near glass smooth. Moly is obviously very soft and if you have a agreesive cross hatch it will eat the moly of in a blink and be a waste of time and money

Gee - I guess he told me :)

Oh - do a little research on bore finish as applied to the term "plateau finish" and you'll find that a glass smooth surface might no be the real ticket...

i use Child$albert Piston ring assemble oil. and love it. I have built alot of motors and use it every time the ring seat fast.. working on a 5.0L with a blower for a mustang, and a 462 for the cobra , scat crank and rods custom pistons. alot of goodies around 700hp

Well I guess glass smoooth is a little exagerated but you know what I am getting at.

Sorry about that Berry R, had no idea till I checked out "Servival Motorsports". I think you qualify. I don't get out often . . . .

Steve

I guess it depends on your definition of professional. :eek:
That was why I let you answer this question. :LOL: