Wow! A lot of posts. Thanks all! I will check them carefully but I don't think I will have to change them.

Just wondering that you guys think. My main bearing are showing about 15% copper on the front upper right side of the front bearing, and the rear lower left side of the rear bearing (looks to be inline with the water pump so i think the previous owner may have tightend it to much, thus wearing the bearing in thoose areas at startup. The front bearing also has a few (3-4) scratches in it down to the copper, like something small went through it, the scratches are small, bout half an inch long and just deep enough to barley catch a nail on them. I was going to replace these bearings but after reading this, and talking with the machine shop i was going to have them pressed in at (they said they looked ok) i might just polish them up a little and use them. Whats everyones opinion? I'll try to get pictures, but my friend has the (crappy) digi cam right now, but ill hopefully get it back this week.

Read above. Uneven wear is never good. If you dont mind the loose clearances, and have an oil system than can support it(the n/a pump cant), you can do like Lynn recommends and take the whole bearing down to the copper. If not, you should replace them.

Thank you for the reply. I did read it, im more worried about the scratches as i can even it out with sand paper as suggested.. a T2 pump is planned in the near future, till then i dont mind it running low at idle. I think im going to go ahead and change them though,.. but i'm still not sure. this is gettign expencive fast and saving another 40 bux (bearings + pressing) would really help out, but not if its going to cost me the motor.

Welcome to the wonderful world of building engines. Im still recovering from the last engine I built...

Lynn, Would the MFR bearings have less of this "overlay" when compared to the REW bearings?

REW bearings have more clearance than the MFR bearings.

I shine them up with 600 or killed 400 in the cleaning tank. The picture is of such a bearing. Note that the overlay is so thin that you can se the copper through it in places. Note also the copper showing in the puzzle lock area.That is normal. If it is not gouged or melted in places, or have dirt welded to it in places, I would say leave it alone. If it shines up quick when you start, it is OK. Any other situation, press in new bearings.





Lynn E. Hanover

Yes, weve established that on a previous thread. Im still trying to figure out the advantages to the Mazda Factory Race bearings, if any. If it has less of this soft "overlay" material, it would ba at an advantage over the REW in a high output engine... theoreticaly.

Lynn, do you just use your finger on the paper to polish the bearings, or a sanding block or what?