Take a look at my bearings.

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wild_maxx
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I just pulled my old motor apart and was looking at the bearings. They are clevite 77's with about 1500 miles on them. Anyone who's ever installed clevites knows theres a grayish color coating on the bearings. Is it normal for that coating to wear off pretty fast? My bearings are pretty shiny (not into the metal/copper of the bearing) and are very smooth. Does this seem normal to you all?

(CLICK FOR LARGER PIC)


NateDogg
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Hopefully Ivan or Chris from AMS will chime in here..

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Chezedik
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Does it just look like little chips of shiny are knocked away? But there are no little 'tracks' or gouges? Can you get better pics? If it is just the first thing, then you are fine. Normally, it would mean that the engine oil had been ran too hot. But on a new motor, it will break in that way.

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Chezedik
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I'm sorry, I didn't know that I needed to click it to get a better pic. Dude, that is great, don't worry so much. Maybe rev'ed a little high early on (a little dry), but if you can't do that, then I have no idea what I am doing here.

Do you have a reason to believe that there is something wrong?

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wild_maxx
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Well I did an oil change at the shop and I was looking at the used oil and found alot of metal shavings. I was pretty sure the bucked was clean before I spilled the used oil into it so the metal shaving had to be from my motor.

I pulled the whole thing apart and have found NO signs of wear on anything. The bearings are smooth and have no deep gouges or wear into them but I was just curious about the grayish covering on the clevite bearings.

Thanks for the info.

TheOne
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yours look like they were ran low on oil(lookin @ how the outer side is ****y, yet the inner is grooved) did you use assembly oil when ya put'em in?

i think ivan said something about usin clevite bearings, believe he does something to'em before he installs them.

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wild_maxx
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Yes I did use ALOT of assembly lube when I put them in. I made sure not to get any finger prints or crap on the bearing surface when I was installing them. I never ran low on oil but I was experiencing low oil pressure one it got hot. (30 psi at 3k rpms when oil was hot) Everything else looked fine in the motor....

Can someone else chime in on the proper procedure to prepping clevite bearings before installing them.... I am deciding if I want run clevites (new one's) in my next built DE-T.

Few more pics of the bearing.This is the top half of the bearing.same bearingRod Cap (bottom bearing) on the left upper bearing on the left.
Modified by wild_maxx at 10:10 PM 4/2/2007

ghx407
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The bearings look fine to me, just used. I've heard on several occasions that it is normal to find some shavings on the first oil change after an engine rebuild. If I remember correctly, the proper procedure was to change the oil and filter after the first 5-10 minutes of the first time the rebuilt engine was started, and to then change oil and filter again several days later after a couple hundred miles.

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wild_maxx
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I changed the oil after 10 miles on the engine. Then at 200 then again at 1k miles.

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Chezedik
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That is normal bearing break-in. If you are concerned, ask a machinist, they will tell you.

AMS machines the bearings before they install them in order to put the oil track all the way around. This prevents starvation. But I think it is probably only necessary in a race engine.

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wild_maxx
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I believe you that the bearings are fine. I am going to replace them on my second motor tho.

Has anyone used the calico coated bearings from AMS? Why do they have the slit down the middle of the bearings?

http://www.amsperformance.com/...=1009

1WheelWonder
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Wild_Maxx sorry to thread jack but it is on topic

I'm having what I think is an issue aswell with low oil pressure when hot, it's funny because mine is at 30psi at 3k too, was this why you broke your engine down, is this oil pressure an issue?

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wild_maxx
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Well I thought that my oil pressure was really low... but that pressure was after driving on the highway for about 30 minutes. The oil gets really hot and it just really thin. On cold start ups I got about 70 psi of oil pressure at idle.. once it warmed up I got about 15 psi of pressure at idle. I wanted to take the motor apart to find out what was wearing down (metal flakes in oil) but after inspecting everything in the motor it all looks fine. My only concern was the bearings but I guess they are fine as well.

Good info on oil pressure.http://www.geocities.com/pcwri....html

1WheelWonder
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Thanks that link was informative

My cold pressure is 50psi at idle and 80 while driving. And I noticed pressure while warm was low-ish after a good 25-30 mile highway cruise.

My cam journals are a little gouged which could cause an issue with pressure

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Chezedik
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1. the slit in the Calico Bearings is the same as the AMS, it is to make sure both sides of the bearing get full lube potential.

2. Oil gets thicker the warmer it gets.

3. 30psi of oil pressure may isn't a problem if you're not starving. In fact, too much pressure can be a real problem for the bearings.

Where are you both sampling oil pressure from? I sample from my turbo and get 5psi, so obviously that is important. Also, how much pressure are you hoping for, you really shouldn't be running much pressure at all.

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wild_maxx
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hot oil gets thicker? I think you might have that backwards?

I was getting my oil pressure reading from the stock oil pressure switch port using an autometer elec. pressure gauge.

1WheelWonder
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I'm using the same spot and gauge as Wild_Maxx, I was just assuming warm cruise oil pressure should be higher than 30psi?

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wild_maxx
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guess not man... its the same pressure on my stock ka24e motor after the oil has heated up.

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Chezedik
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No, I have it right, hot oil gets thicker. The oil you are running is most likely a 5W30. This means it's cold weight is an SAE 5 viscosity, it's warm weight is 30. The scale is not inverse, so, 30>5. This is because of additives in the oil which were put in to prevent oil from getting thinner when it heats up.

What place is it that you both have your gauge reading from?

1WheelWonder
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I'm using the port inwhich the factory oil pressure sensor is located and am assuming Wild_Maxx is using the same from what he stated above.

I use a 10w 30 (mobil1)

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wild_maxx
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yep oil pressure is comming from the stock ports off the oil filter block.

I was running a regular 10w30 motor oil.

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Chezedik
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Yeah, I couldn't fit mine back there. Like I say, pressure is good, bearings are good, put it back together and boost!

1WheelWonder
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What is typical oil pressure for our engines cold/hot

What oil pressure is best (opinions) for our engines?

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Chezedik
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FSM says idle = 11psi, 3000rpm = 60-70psi. Were you both using oil pressure gauges or using oil pressure testers?

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wild_maxx
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I was using a gauge.

I won't be putting that motor back together tho.... i'm doing a built DE-T with a precision sc44 powering it.

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Chezedik
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Good deal. Enjoy.

SonyPete
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Quote »No, I have it right, hot oil gets thicker. The oil you are running is most likely a 5W30. This means it's cold weight is an SAE 5 viscosity, it's warm weight is 30. The scale is not inverse, so, 30>5. This is because of additives in the oil which were put in to prevent oil from getting thinner when it heats up.[/quote]Ummm Chezedik there is no way oil gets thicker as it warms up, that goes against just about any physics concept out there. The 2 part weight system used by oils describes how thick the oil can get and how thin it gets. Say for instance 10W30, thats weight shows that the oil gets no thicker then a normal 10 weight oil during cold startup and doesn't get any thinner then a 30 weight oil at operating temperature. You have the weight system correct and that it uses additives to change the characteristics of the oil. But the additives only keep it from thinning so much does not make it thicker, only slows down the thinning process.

Modified by SonyPete at 11:09 PM 4/6/2007
Modified by SonyPete at 8:41 AM 4/7/2007

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Chezedik
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Get over it. There are additives that cause it to get thicker as it heats up. Crack a book, and you will find it. That is better living through chemistry.

SonyPete
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Not sure what you mean by get over it or "better living thorugh chemistry" when your the one saying oil gets thicker as it heats up. Like I said before the additives only reduce by how much the oil thins out. Does not get thicker. Only way you can use the terminology "thicker" is if you compare a pure oil with one with additives and yes the one with additives would be "thicker" due to it not thinning as much as the pure oil.

http://www.sportrider.com/tech/146_0308_oil/

Quote ». In order to overcome the natural thinning that occurs as oil heats up, a component known as a viscosity modifier is added. This is a complex polymer that swells due to heat, the net result being that the oil thins less.[/quote]Hence it doesn't make the oil thicker, it becomes less thinner, as it only slows down the thinning process like I have said already. Your saying that for any given visocity the moment you add heat it will become thicker(higher visocity) which is incorrect. Once you add extra heat it will thin just not as much as a pure oil. No sense it getting upset I was just clarifying a few things for the others reading this thread.

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Chezedik
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Okay, I will give you that. If anything a 5W30 is a 30 weight oil whose additives allow it to operate as a 5 weight when it is cold. The additives do not make it thicker when it is hotter. I think that I may have been unclear on that, and I am sorry.


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