Posted By: Guitar Jones
do you oil the back side of a bearing shell? - 04/29/11 05:55 PM
I never have but I've seen others that do so what's your opnion?
do you oil the back side of a bearing shell?
Posted By: JohnRR
Re: do you oil the back side of a bearing shell? - 04/29/11 05:59 PM
Why would one , it doesn't move , or at least it shouldn't ?
Posted By: Dunnuck Racing
Re: do you oil the back side of a bearing shell? - 04/29/11 06:14 PM
Nope,I wipe mine clean and install them dry,then lube the bearing surface.
I want nothing between the back of the bearing and it's mating surface so it can transfer heat out as well as possible.
Keith
I want nothing between the back of the bearing and it's mating surface so it can transfer heat out as well as possible.
Keith
Posted By: chryco
Re: do you oil the back side of a bearing shell? - 04/29/11 06:20 PM
Nope,I wipe mine clean and install them dry,then lube the bearing surface.
I want nothing between the back of the bearing and it's mating surface so it can transfer heat out as well as possible.
Keith
I want nothing between the back of the bearing and it's mating surface so it can transfer heat out as well as possible.
Keith
Posted By: SportF
Re: do you oil the back side of a bearing shell? - 04/29/11 06:22 PM
I do as that engine might sit around a while before firing and I don't want any rust in there. I always make sure all interior parts are coated with oil to prevent rust. A number of years ago I built an engine for my street rod and after sitting for a couple of years in the chassis it wouldn't turn over very well and I ended up taking it apart to clean it up. I usually bag it and seal with a dryer now, but everything still gets oiled. Engines are a great place for condensation, even inside an insulated garage.
Posted By: hemigod426
Re: do you oil the back side of a bearing shell? - 04/29/11 06:33 PM
i use one drop of 3-1 oil on back of each bearing spread out with finger,so mains/rods bearings seat perfect in saddles while torque is applied 
Posted By: B G Racing
Re: do you oil the back side of a bearing shell? - 04/29/11 08:32 PM
No 
Posted By: ZIPPY
Re: do you oil the back side of a bearing shell? - 04/29/11 09:18 PM
No
Posted By: Crizila
Re: do you oil the back side of a bearing shell? - 04/29/11 09:37 PM
Yes - but I'm not sure I'm right. 
Posted By: rowin4
Re: do you oil the back side of a bearing shell? - 04/29/11 09:38 PM
About 40 some years ago a engine builder told me not to touch the back side of the bearing and bearing surface and bearing seat area with your fingers after wiping down the areas with a clean cloth.I don't even use my finger to spread out the oil on the journals. Been doing that on every build since. Can't see why you would oil the back side. 
Posted By: Guitar Jones
Re: do you oil the back side of a bearing shell? - 04/29/11 09:43 PM
Interesting comments. The way I looked at it is that with oil on the backside there may be a tendancy for a little extra crush on the bearing. If or when that oil eventually vacates the saddle it may leave the bearing shell just a tad looser and since the crush is the only thing that keeps that bearing from spinning it doesn't seem like a good idea to me.
Posted By: dartman366
Re: do you oil the back side of a bearing shell? - 04/29/11 09:44 PM
No, leave them dry.
Posted By: dOc !
Re: do you oil the back side of a bearing shell? - 04/29/11 09:46 PM
Oil ? ... I have always cleaned-'em-off real-good with some type of solvent or gas.
Posted By: Dean_Kuzluzski
Re: do you oil the back side of a bearing shell? - 04/29/11 09:46 PM
Quote:
I want nothing between the back of the bearing and it's mating surface so it can transfer heat out as well as possible.
Keith
I assemble mine dry on the backside.....................
but as for heat transfer, it seems like, to me, a layer of oil would actually tranfer heat better. More molecules of matter providing surface contact. But I think too much about stuff anyways.
Posted By: Steve1118
Re: do you oil the back side of a bearing shell? - 04/29/11 09:46 PM
I go even further....it's probably overkill, but I dip the bearing shell in lacquer thinner, then use a rag dipped in lacquer thinner to wipe the saddle clean before installing the shell. I've done it that way for forty years.
So....absolutely not. No oil or substance of any kind between the shell and the saddle.
So....absolutely not. No oil or substance of any kind between the shell and the saddle.
Posted By: CompWedgeEngines
Re: do you oil the back side of a bearing shell? - 04/29/11 09:47 PM
No.
Crush is set by the actual ID of the bearing bore period. The bore is measured dry, and bearings are installed dry ( backside). Anything that is not the original parent bore, shouldnt be there, including dust, schars of metals, lint,. paper towel fragments etc.It also always a good idea to take a dressing stone and lightly champher all the outside edges of the bearing bores, as often ( especially newly reconditioned rods) they can slightly mushroom there and actually hold the bearing up slightly.
Crush is set by the actual ID of the bearing bore period. The bore is measured dry, and bearings are installed dry ( backside). Anything that is not the original parent bore, shouldnt be there, including dust, schars of metals, lint,. paper towel fragments etc.It also always a good idea to take a dressing stone and lightly champher all the outside edges of the bearing bores, as often ( especially newly reconditioned rods) they can slightly mushroom there and actually hold the bearing up slightly.
Posted By: Streetwize
Re: do you oil the back side of a bearing shell? - 04/29/11 09:58 PM
Leave em dry but I clean the bearing surfaces with ATF, not for lubrication but for corrosion resistance as I would with any newly machined surface exposed to atmosphere and moisture. I also swab all the cylinder and lifter bores with ATF until every bit of grit/dust/dirt is out of them and they wipe perfectly clean before assembly. ATF on a white cloth shows eveen the slightest bit of dirt plus it's so thin it cleans all the nooks and crannies.
Probably old school as all get out but that's my gig and I ain't blowed one up yet!! grin:
Probably old school as all get out but that's my gig and I ain't blowed one up yet!! grin:
Posted By: FastmOp
Re: do you oil the back side of a bearing shell? - 04/29/11 10:22 PM
Yep. I didn't till Garlits told me too lol. He said it gets back there anyway 
Posted By: Sport440
Re: do you oil the back side of a bearing shell? - 04/29/11 11:04 PM
Quote:
Yep. I didn't till Garlits told me too lol. He said it gets back there anyway
I allways put them in as dry and as clean as possible. Thinking that, it would give more resistance to spinning the bearing in a low oil psi situation.
Last month I was having some fitness issues with some mains on a RB and had the crank in and out several times.
No matter how clean I got the back side of the bearing, and its saddle. The oil found its way back there. They were clean when I put them in, but they had lube between the bearing and saddle after everytime I took them out.
Posted By: rickraw
Re: do you oil the back side of a bearing shell? - 04/30/11 12:04 AM
dry. if u build an engine & it's going to sit 4 a while, just prime it, oil will get where it supposed 2. seeya.
Posted By: Guitar Jones
Re: do you oil the back side of a bearing shell? - 04/30/11 12:44 AM
Quote:
No.
Crush is set by the actual ID of the bearing bore period. The bore is measured dry, and bearings are installed dry ( backside). Anything that is not the original parent bore, shouldnt be there, including dust, schars of metals, lint,. paper towel fragments etc.It also always a good idea to take a dressing stone and lightly champher all the outside edges of the bearing bores, as often ( especially newly reconditioned rods) they can slightly mushroom there and actually hold the bearing up slightly.
This was my line of thinking however, almost any factory service manual I've read says to oil both sides. I don't understand why but I'm not an engineer, just a flat rate tech.
I appreciate all the opinions and responses, the reason I asked is because I plan to assemble my 408 short block this weekend and if there was a compelling reason to do it one way or the other I wanted to hear it.
Thanks all, I guess I'll just install them clean and dry on the backside.
Posted By: Crizila
Re: do you oil the back side of a bearing shell? - 04/30/11 03:11 AM
I guess if oil gets back there anyway, it's pretty much of a moot point? If you put them in dry, and the saddles are dry and all stays dry, thats bare steel on bare cast iron, and in an environment that propagates moisture drop out, that = corrosion. JMO.
Posted By: Hot 340
Re: do you oil the back side of a bearing shell? - 04/30/11 03:26 AM
Put them in however you want, as stated, it gets back there. Never took one apart that was dry behind the bearings.
Posted By: CMcAllister
Re: do you oil the back side of a bearing shell? - 04/30/11 03:40 AM
Lightly clean backside with fine Scotchbrite in parts washer to polish, remove burrs, etc.
Wash in parts washer.
Wipe clean with paper towel with lacquer thinner and blow and clean with compressed air.
Wipe block or rod bore clean with paper towel and lacquer thinner and blow dry and clean with compressed air.
Install bearing shell dry. Tap lightly on ends to seat.
Oil with assembly lube of choice just before assembling.
Wash in parts washer.
Wipe clean with paper towel with lacquer thinner and blow and clean with compressed air.
Wipe block or rod bore clean with paper towel and lacquer thinner and blow dry and clean with compressed air.
Install bearing shell dry. Tap lightly on ends to seat.
Oil with assembly lube of choice just before assembling.
Posted By: hemigod426
Re: do you oil the back side of a bearing shell? - 04/30/11 03:48 AM
only do one drop of super light oil for easy install thats it,not use lube or full weight oil or anything like that, thrust bearings for sure go in so much nicer with one drop of light oil on back side, then dry. its not going to upset set anything for spec,ive touched/wet sanded/bearing knifed them like crazy never had one spin yet
Posted By: mike s
Re: do you oil the back side of a bearing shell? - 04/30/11 07:28 AM
Dry always.I did know of some experiments builders tried with various liquids back in the day.No difference in performance.
Posted By: dOc !
Re: do you oil the back side of a bearing shell? - 04/30/11 07:34 AM
.... here is another way. How about a dab of red or blue locktite ? ... was talking to a guy I know up here he has done this for years. He races dirt 1/4 mile.