Doing the rod bearings, and have a few questions

[Devin]

(Pictures to come)
1. I started my bearing job yesterday and I pulled off the cap on journal 5. The bottom bearings look great, with no copper showing, but the top bearings definitely show copper. I figured out how to plastiguage, but going lengthwise across the bearing the plastigauge was at .0015 on one side and a little bit smaller than .002 on the other. Did I not torque it correctly? I do have to say there is definitely more wear on the edge of the bearing that is closer to .002, as the copper is shown to the edge, where as at the other edge there isn't any showing. Is this cause for concern or can I just put the normal sized bearings in?

2. I noticed there is a "front" bearing and a "thrust bearing" and even an "intermediate front" bearing. I haven't looked at all of them in the package, but are there actual differences, or is that just for reference?

3. I accidentally pushed the piston too far out of the cylinder and one of the rings popped out a bit (and it was quite dirty). I compressed it back in and pushed the cylinder back down, but since it was a. dirty and b. popped out, do I have to replace them?

 

[Off Road SHO]

(Pictures to come)
1. I started my bearing job yesterday and I pulled off the cap on journal 5. The bottom bearings look great, with no copper showing, but the top bearings definitely show copper. I figured out how to plastiguage, but going lengthwise across the bearing the plastigauge was at .0015 on one side and a little bit smaller than .002 on the other. Did I not torque it correctly? I do have to say there is definitely more wear on the edge of the bearing that is closer to .002, as the copper is shown to the edge, where as at the other edge there isn't any showing. Is this cause for concern or can I just put the normal sized bearings in?

2. I noticed there is a "front" bearing and a "thrust bearing" and even an "intermediate front" bearing. I haven't looked at all of them in the package, but are there actual differences, or is that just for reference?

3. I accidentally pushed the piston too far out of the cylinder and one of the rings popped out a bit (and it was quite dirty). I compressed it back in and pushed the cylinder back down, but since it was a. dirty and b. popped out, do I have to replace them?

You should plastigage the new rod bearings, not the old. Make sure you remove any old oil from the crank, rod and cap before inserting the bearing; place the piece of plastigage on the cap bearing offset about 3/4" from the six o'clock position; torque in two stages; remove cap and compare width of smashed gage to scale on the plastigage package; write it down. Remove smashed plastigage residue from bearing AND crank journal with fingernail. Push rod back up away from crank again and apply assembly **** of choice to rod bearing and cap bearing, NOT to the back side of either bearing. With your thumbs between the the rod bolts and the crank journal (so you don't accidently run a rod bolt into the crank) carefully pull the rod back onto the crank journal, verifying that the detent is still in its' pocket in the rod. Verify same with rod cap and bearing and slide cap onto the rod bolts. The bolts and holes are precision so they must be lined up accurately for them to slide.

As far as pushing the piston back down after a ring or two has popped out; as long as you don't rotate the rings out of their 90 or 120 degree offset, and you don't damage the ring landings, you should be okay. Carbon buildup is normal around the first two rings.

Unless the original bearings are oversize (will have oversize dimension stamped on the back such as .25, .50 or .75) you should be okay with standards.

The mains are different. Use assembly **** or lithium grease to help stick the thrust bearings in their grooves. Make sure the oil slots face the moving part which is the crank.

Good luck.

Tom

 

[Devin]

Wow, thanks for the detailed how-to. Just a couple items for my clarification.

1. I need to plastigauge just the new, bottom bearing (cap bearing), but not the rod bearing? That would definitely make it easier...
2. I apply **** to the journal side of each bearing. I assume enough to cover it, but not go buck wild.
3. "verifying that the detent is still in its' pocket in the rod." - I don't quite understand what that means.
4. All of the rod and cap bearings are the same, I just have to make sure to orient them in the rod and cap correctly.

Thank you so very much. Sometimes the Chilton and I are not quite adequate to do this.

 

[Ishodu]

To answer #3 there is little notches bent in the rod bearings they have to sit in the pocket on the rod bearing caps.

 

[Off Road SHO]

Wow, thanks for the detailed how-to. Just a couple items for my clarification.

1. I need to plastigauge just the new, bottom bearing (cap bearing), but not the rod bearing? That would definitely make it easier...
2. I apply **** to the journal side of each bearing. I assume enough to cover it, but not go buck wild.
3. "verifying that the detent is still in its' pocket in the rod." - I don't quite understand what that means.
4. All of the rod and cap bearings are the same, I just have to make sure to orient them in the rod and cap correctly.

Thank you so very much. Sometimes the Chilton and I are not quite adequate to do this.

#1 Yes, plastiguage just the gap between the cap bearing insert and the crank.

#2 Go buck wild, it doesn't hurt anything to have more. I use STP oil treatment that I bought in 1976. I'm still using the same can after probably 20-25 engine jobs. It cost me 89 cents back then. I REALLY like to get my money's worth.

#3 Answered above.

#4 That's correct, the oil hole in the bearing is wasted on cap side and used on the rod side. If you don't line up the detents with the pockets, 1) you will lock up the crank tighter than me at a leberal fund raiser, and 2) the oil hole in the bearing might not line up with the oil hole in the rod.

However you mentioned thrust bearing, which implied that you were doing the mains also. I didn't want you to drop an upper thrust bearing side plate when you were reaching for the main cap. And don't ask me how I know it's possible.

Tom

 

[Devin]

Thanks again for the help guys, I am really beginning to understand this now.

I'm not actually doing the mains (unless someone tells me that I really need to do them now that the engine is apart) but the Chiltons had an exploded view of the rod bearings, cap bearings and I could have sworn it was a view of a bearing with a description of Front bearing and thrust bearing. Maybe it was the mains and I was a bit !

 

[F-22 Raptor SHO]

Thanks again for the help guys, I am really beginning to understand this now.

I'm not actually doing the mains (unless someone tells me that I really need to do them now that the engine is apart) but the Chiltons had an exploded view of the rod bearings, cap bearings and I could have sworn it was a view of a bearing with a description of Front bearing and thrust bearing. Maybe it was the mains and I was a bit !

I had 135,000 on my mains when I did my bearings...they didnt look bad at all, but I changed them simply because an investment of another 40 bucks gave me the piece of mind I wanted. That and the fact that my time is important to me. Seeing how long it took to get all that crap off just to access the bearings to begin with was reason enough to do it.

 

[Off Road SHO]

Seeing how long it took to get all that crap off just to access the bearings to begin with was reason enough to do it.

Amen to that, brother. Amen to that.


Tom

 

[SHO_Diehard]

A few other points...

The experienced guys may be confident enough to pass on this, but I like to put rubber hose over the rod bolts to prevent scratching the rod journal. I cut the length so they slide right over the bolt and down to the rod split and still cover the bolt by 3/16" or so.

My shop manual said to use moly **** on the rod bolts before torquing. I believe this is to get accurate torque readings.

This is just my opinion, but don't use a 1-150 lb torque wrench on your rod bolts, get one that's scaled for the range you are in, say 0-50 IIRC.

 

[F-22 Raptor SHO]

Amen to that, brother. Amen to that.


Tom

Yea, besides, the guy who let me use his garage might start chargin me rent seeing as how I have more horizontal miles on the lift than vertical miles on the road.

 

[Devin]

I hope you don't have many vertical miles on the road

Well, I don't really want to make this take longer than it already has (bought the car in Oct 2002), but if the Mains aren't really much harder to do than the rod/cap bearings I'll do them.

 

[revhardSHO]

The main bearings require alot more work to change out than the RBs. Dont worry about them. There is really no need to plastigauge new bearings if the motor hasnt been knocking / noisy and if the old RBs look okay. Just puts more stress on the rod studs and leaves more room for error.

 

[SHOtimer]

The main bearings require alot more work to change out than the RBs. Dont worry about them. There is really no need to plastigauge new bearings if the motor hasnt been knocking / noisy and if the old RBs look okay. Just puts more stress on the rod studs and leaves more room for error.

What more has to be done in order to swap the main bearings?

Doug

 

[Off Road SHO]

What more has to be done in order to swap the main bearings?

Doug

Because you can't push the block away from the crank to get the top main half out, it's a little more difficult, but still easy. I've used lots of different homemade bearing pushers over the years. Anything about the thickness of the bearing and flexible and non scratching can be used.

I've used: q-Tips with the cotton removed, plastic battery carrying straps, feeler guages that have been polished with steel wool, and bare #10 copper wire.

Don't take all of the main caps off at once, take only the two closest to the one you're doing. If one is being stubborn, loosen all the main bolts but don't remove them.

Tom