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ricardoa1
10-12-2005, 10:23 PM
I did a search. But I have found limited answers. I wiped some of my bearings when I had my cam installed wrong by me. So I have torn down the whole thing and want to replace the bearings {since some got scored} and wash this engine down. So I am looking for bearings. I have Clevite 77 .50mm undersize on there right now, I think I can get away with just replacing the bearings, the journals look ok aside from one hair line scratch on one of them. I am looking for Sealed Power this time around, But they make Aluminum ones and Tri-metal ones. Whats the difference aside from the the obvious? Can anyone help me out with #s and places, and maybe some recomendations. Also I think I did most of the damage is on the skirts of the JE Pistons. The cyl walls look ok But every piston has metal shavings and dirt embeded and lines of scratches. Is there something I can do about it I dont want to buy new ones.

Mike8675309
10-12-2005, 10:42 PM
Have you seen this post?
http://www.sccoa.com/forums/showpost.php?p=351022&postcount=13

It's recommended Felpro main bearings by Steve (BlackbirdSC) over the Clevite units and I trust his opinions on this.

ricardoa1
10-13-2005, 02:28 PM
Have you seen this post?
http://www.sccoa.com/forums/showpost.php?p=351022&postcount=13

It's recommended Felpro main bearings by Steve (BlackbirdSC) over the Clevite units and I trust his opinions on this.

As far a I know felpro only makes gaskets. the parent co is Federal mogul. And they make sealed power bearing. But by my search it seems that they only make 25mm undersize is that correct anyone? I am also looking at King bearings anyone know part # for them that are 50mm undersize?
BTW I am shooting for over 400rwhp and then some spray. :)

XR7 Dave
10-13-2005, 03:40 PM
You might want to reconsider that .020" under crank. Just a thought. Sealed Power and King are both good bearings.

ricardoa1
10-13-2005, 03:56 PM
Dave my engine was rebuilt 1000 miles ago. I had a reman crank from ford that came with matching bearings and that was what was there. So I dont want to machine if I can help it. I just want the replacement bearings. I now application info or place where they sell it. Their website is very vague.

Mike8675309
10-13-2005, 04:10 PM
Felpro - Federal Mogul - Sealed Power - misc others... all the same company. I get the names all confused.

their website isn't working now, but you can lookup part numbers and applications there.
http://www.federal-mogul.com

ricardoa1
10-13-2005, 05:09 PM
Felpro - Federal Mogul - Sealed Power - misc others... all the same company. I get the names all confused.

their website isn't working now, but you can lookup part numbers and applications there.
http://www.federal-mogul.com

I did and for the SC application they only have standard OEM and 25mm oversize. They also have two part # that confuses me even more they also call it aluminum? :confused:

Mike8675309
10-13-2005, 07:05 PM
The size limitation is due to the manufacturers recommendation that you throw the crank away if it needs to be ground down any more than that. If you need more than .25mm, you won't want to put all that much power through your motor anyway, and go ahead with Clevite bearings.

7371MA is the number.
Info on the bearing materials is here:
http://www.federal-mogul.com/cda/content/front/0,2194,2442_2875_6752,00.html

There is Aluminum, Copper-Lead, and Babbit. Aluminum is used mostly for it's anti-corrosion properties.

BlackbirdSC
10-16-2005, 10:29 PM
Get the King bearings if you can. When I did my motor a couple years ago, they hadn't started making the SC mains. The Federal's are also great bearings but usually a little more $$. And actually the SC # is 7086M or 7086MA (the newer aluminum series bored bearings which are better than the old bi or tri metal).

King SC catalog listing (http://www.king-bearings.com/cat/panel/pan1224.htm)

They make them up to .040 (1mm) and they're 3/4 groove.

As for the pitching it at .020"... the crank itself won't be weakened significantly being ground even .040" on the mains. On the rods...maybe like 5%. One of the reasons Federal doesn't make a bearing past .010" is hardly anyone would buy it. There's only 80,000 SC motors out there and how many will use a .020", .030" or .040" bearing? Also, the cranks had a fillet on them (rounded edge where the journal meets the rest of the crank). Many grinders don't recut the fillet and make a sharper edge there. Not a big deal on a 'normal' engine but would weaken the crank. I'd take a .040" regrind if the fillet was at it's max. It would actually be stronger than a std crank if the fillet still fit the bearings (never tried, but it would be stronger if the bearings fit)

The new King bearings are the SI series and have silicon injected in them like many OEM bearings have had since the late 90s.

You want CR6619SI for the rods and MB4052SI for the mains. If you can't find them, call Jim at Auto Parts Exchange (724 935 1551). Tell him I looked up those numbers and MotorState at least lists them as special order. He can probably get you a set of rods and mains shipped for less than the Federals .

Later,
Steve

ricardoa1
10-16-2005, 10:51 PM
Thanks I almost bought the clevite right before I read your post. I can buy straight from kings right, are they more expensive? The main are are .050" like I stated but the rods are .025".

Oh and here are some pics of the crank maybe you guys can tell me if Ill be ok with it.

ricardoa1
10-16-2005, 10:55 PM
Here are some more. I hope I can just slap on new bearings and that it.

ricardoa1
10-16-2005, 11:02 PM
Here is my biggest problem I have the pistons look like they are junk. Can they be polished? Every single one had the same problem. What is the most cost effective solution.?

CMac89
10-16-2005, 11:14 PM
Here is my biggest problem I have the pistons look like they are junk. Can they be polished? Every single one had the same problem. What is the most cost effective solution.?
I get that alot whenever I build brand new motors for my race cars. The polished/dull looking spot in the cylinder followed by some scratches on the bottom of the bore is caused by tight piston-to-wall clearances. That's an easy thing to solve because all they have to do is hone the cylinder out to about .007-.010. If you dont know what the clearance is now I'd bet it's around .004 or so.

About the mains, if it has good clearances the ONLY thing that can ever tear a MAIN bearing up is not enough oil in the motor.

Dirt can also put scratches in cylinder walls easily.

Mike8675309
10-17-2005, 11:14 AM
Great info from Steve there, I know I really appreciate his info. Gotta save that.

Just looking it's hard to know with your pictures. I'd say the cylinders need to be honed. Have you checked the clearances on anything. The crank pictures aren't clear enough for my un-trained eye.

BKB
10-17-2005, 02:24 PM
There is nothing wrong with Clevite tri-metal berings. I wouldn't use anything else in a low boost motor. They have saved my motor with there great embedability. Some people say they are to soft and can deform under great combustion pressure (boost over 18psi) or sever detonation. I haven't seen any sign of this myself, my motor runs 15psi and i have detonated that motor for a long time. After a tear down the bearings showed no sing of deforming. I probably wouldn't use them on rod beaings in a high boost motor, Coy Miller agread and said himself he wont use them on high boost motors also.